Field

[0001] Embodiments of this disclosure relate generally to pneumatic tires.

BACKGROUND

[0002] Free rolling tires, such as those mounted on a Class 8 trailer used in long haul applications, often develop an irregular wear bias which typically manifests itself as a characteristic wear form in which the inside shoulder area of the tire wears out significantly more rapidly than the outside shoulder of the tire. Fundamentally, the primary contributor to the inside wear bias is considered to be deflection of the axle or axle beam when the trailer is under load. This deflection results in the creation of a slight negative camber at each wheel end, such as approximately -0.5°, for example.

[0003] Observers of trucks operated on drive-on-the-right-side-of-the-road (“right hand traffic”) jurisdictions may notice that although the negative camber is roughly the same on all wheel ends of a given trailer, the extent of the inside wear bias tends to be noticeably worse on a left hand (LH) tire (wheel) position than on a right hand (RH) wheel position. In right hand traffic jurisdictions, the LH tire (wheel) position is located closest to the road centerline relative to the RH tire position, and therefore is located uphill relative to the RH tire position due to a crown formed in the road (road crown), such as may be provided to evacuate standing water from the road surface. This observation of increased wear on the LH tire (more generally, an uphill tire) evidences the presence of factors other than camber influencing this increased LH (uphill) tire wear.

[0004] It has been determined that the anticipated influence of gravity resulting in a particular tire designs having unidirectional plysteer impact these situations in which uphill tires experience tread wear issues. Plysteer (which is also referred to as“ply steer”) generally describes a lateral force generated by a radial tire as it rolls under load. There are many tire design and construction considerations that can influence plysteer, but of primordial influence is the angular orientation of the reinforcements (cords or cables) arranged in each belt ply used to form the belt below the tire tread. When overlaying these belt plies, the reinforcements generally form an overlaid "X" arrangement as the reinforcements of one belt ply extend in a positively angled direction and the reinforcements of the other belt ply extend in a negatively angled direction relative to a equatorial centerline (that which forms an equatorial plane). While the relative difference between the two directions affects plysteer, the angular orientation of reinforcements in the belt ply arranged closest to the tread of the tire (that is, the radially outermost belt ply) will likely define the direction of the tire's plysteer force.

[0005] Due to the presence of road crown, tire manufacturers make a conscious choice to orient belt ply reinforcements for all wheel positions in such a way as to generate a lateral force considered to be oriented in an uphill direction to at least partially counteract the anticipated influence of gravity due to the presence of road crown. For example, tires for all tire positions designed for drive-on-the-right-side-of-the-road jurisdictions have the radially outermost belt ply oriented in such a way as to exert a leftward direction lateral force. This is because gravitational forces imposed by the prevailing the slope of the crowned road surface will try to pull the vehicle rightward toward the low side of the road. Having tires that tend to pull leftward is deemed preferable to oppose a vehicle's tendency to drift/pull rightward due to gravity. For drive-on-the-left-side-of-the-road jurisdictions, the logic is the same, but the generation of lateral forces are reversed. Due to the use of tires designed to generate unidirectional plysteer on a vehicle and the presence of the negative camber as discussed above, it is appreciated that differences in tread wear may exist between free-rolling tires on opposing sides of a vehicle without the presence of road crown. It is the anticipated use of tires on crowned roads that has caused tires to be configured to generate lateral plysteer forces in all wheel positions on over-the-road vehicles that creates the differences in tread wear when combined with the presence of negative camber. Accordingly, there is a need to overcome this wear issue for opposing, free rolling tires on over-the-road vehicles, such as long-haul trailers, for example.

SUMMARY

[0006] Particular embodiments of this disclosure include methods of improving tire wear on a vehicle, the vehicle including a pair of opposing, free-rolling tire positions generally located along a common rotational axis, where the pair of opposing, free-rolling tire positions are arranged on opposing lateral sides of the vehicle relative to a widthwise centerline of the vehicle. The pair of opposing, free -rolling tire positions includes a first tire position arranged on the first side and a second tire position arranged on the second side. The methods include mounting a first tire to the vehicle in the first tire position; and, mounting a second tire to the vehicle in the second tire position. The first tire is configured to generate a lateral plysteer force in a first direction when the first tire is loaded during vehicle operation and the second tire is configured to generate a lateral plysteer force in a second direction when the second tire is loaded during vehicle operation, the first direction being directed toward the vehicle widthwise centerline the first direction being opposite the second direction.

[0007] Other embodiments described herein provide a vehicle including a pair of opposing, free-rolling tire positions generally located along a common rotational axis, where the pair of opposing, free-rolling tire positions are arranged on opposing lateral sides of the vehicle relative to a widthwise centerline of the vehicle. The pair of opposing, free -rolling tire positions includes a first tire position arranged on the first side and a second tire position arranged on the second side. The first tire is configured to generate a lateral plysteer force in a first direction when the first tire is loaded during vehicle operation and the second tire is configured to generate a lateral plysteer force in a second direction when the second tire is loaded during vehicle operation, the first direction being directed toward the vehicle widthwise centerline, the first direction being opposite the second direction.

[0008] The foregoing and other objects, features, and advantages will be apparent from the following more detailed descriptions of particular embodiments, as illustrated in the accompanying drawings wherein like reference numbers represent like parts of particular embodiments.

DETAILED DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a side elevational view of a loaded tire arranged along a ground surface;

[0010] FIG. 2 is a downward view of a tire partially sectioned to show the belt plies forming a belt in a tire;

[0011] FIG. 3 is a sectional view of the tire shown in FIG. 2 taken along line 3-3;

[0012] FIG. 4 is a downward view of a tire partially sectioned to show the belt plies forming a belt in a tire;

[0013] FIG. 5 is a sectional view of the tire shown in FIG. 4 taken along line 5-5;

[0014] FIG. 6 is an elevational view of a free-rolling axle of a vehicle arranged along a ground surface forming a crowned road, the road being a right-side driving jurisdiction;

[0015] FIG. 7 is a rear view of a free-rolling axle such as is shown in FIG. 6, the tires being partially sectioned to show the radially outermost belt ply, where the radially outermost belt ply for each tire is arranged in accordance with the prior art; and, [0016] FIG. 8 is a rear view of a free-rolling axle such as is shown in FIG. 6, the tires being partially sectioned to show the radially outermost belt ply, where the radially outermost belt ply for each tire is arranged in accordance an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0017] This disclosure describes tires configured to generate lateral plysteer forces in opposing directions to improve tire tread wear performance for free-rolling tires installed on a vehicle. This disclosure also described the implementation of these tires on vehicles.

[0018] These tires are pneumatic tires designed for, and installed upon, a vehicle having opposing, free-rolling tire positions. Opposing, free-rolling tire positions comprise tire positions arranged laterally opposite one another on opposing lateral sides of the vehicle relative to a widthwise centerline of the vehicle. In certain instances, these free-rolling tire positions are rigid, meaning each is a non-steering tire position. In being free-rolling, a tire position is not driven, at least during certain periods, during powered (driven) vehicle operation. What this means is that during powered vehicle operation, while a tire position may be a fully dedicated free-rolling tire position that is not configured to be driven, there may be tire positions that are configured to be selectively free -rolling and selectively driven at different periods during powered vehicle operation. It is appreciated that any such vehicle may be powered or unpowered. For example, a powered vehicle may form an over-the-road car, truck, or tractor, while an unpowered vehicle may form a trailer or a converter dolly. In one example for powered vehicles, non-steering free-rolling tire positions are arranged at the rear of a front-drive vehicle. The benefits described herein may be especially useful to improve wear performance in non-steering, free-rolling tire positions, especially in situations where tires positioned opposite one another on opposing sides of the vehicle experience negative camber. Under such conditions, the loaded vehicle generates a slight negative camber for each opposing, free-rolling tire position. For example, the slight negative camber may extend up to -0.5 degrees or up to -1.0 degrees. It is anticipated that even greater negative camber may occur. The issue of imbalanced wear between left and right side tires is most often observed when a vehicle is operating under loaded conditions on a crowned road. The crown in the road may peak at or near the road centerline, such as when left and right lanes are arranged along a common road surface not separated by a non-road median. In other situations, the crown may increase between opposing sides of a road surface, such as when a median is arranged between left and right hand sides of the road. Other situations may arise, but in any event, the road surface has an elevational slope to create a crowned road surface. Improvement in wear performance may mostly be achieved for the tire position located on the uphill side of the vehicle. In situations where the road crown peaks at or near a road centerline (the road-center side tire position), the uphill side of the vehicle is located closest to the road centerline. These improvements may be especially beneficial when the tire tread is formed of an elastomeric material that is rather slow wearing, which is more sensitive to these wear issues. Low hysteresis elastomeric tread material can be described using a material property referred to as tan delta (“tan(5)”)· Tan(5) (also referred to as a loss factor) is a dynamic property of the elastomeric tread material (the rubber compound). The present understanding is that because the low hysteretic material absorbs less energy, these wear issues arise more quickly than with higher hysteresis tread material.

[0019] Opposing, free-rolling tire positions are generally arranged along a common rotational axis, meaning, tires in each opposing position are either arranged along a common rotational axis or within a slight deviation thereof, on opposing lateral sides of the vehicle (that is, left and right sides of the vehicle). In being so arranged, the opposing, free-rolling tire positions may be located on opposing ends of a solid axle, which is also termed a beam axle. It can also be said the solid axle connects the opposing tire positions. Because each such axle is not powered, each such axle is also referred to as a dead axle. Also, because no such axle permits steering, each non-steering tire position is rigid. At each end of the axle, a hub is commonly arranged to facilitate attachment of a wheel to which a tire is mounted. A tire mounted on a wheel is referred to as a tire/wheel assembly. It is possible that independent axles may be arranged on opposing sides of the vehicle for each opposing, free-rolling tire position, which do not connect each opposing tire position but which are still generally arranged along a common rotational axis and which are non- steering. These independent axles are not commensurate with independent suspensions, but rather remain rigid and do not pivot relative to the vehicle or vehicle frame.

[0020] To improve tire wear performance between a pair of opposing, free-rolling tire positions on a vehicle for the tires to be installed at these positions, where the opposing free- rolling tire positions will experience negative camber during vehicle operation, the plysteer generated by one tire is negative while the plysteer for the other tire is positive. In saying that the plysteer is positive or negative, reference is made to the resulting lateral plysteer force being positive or negative. Stated differently, negative and positive lateral plysteer forces are directed in opposing lateral directions. It is appreciated that any industry accepted sign convention may be employed, where a negative lateral plysteer force may be directed in any one lateral direction (that is, in an axial direction of the corresponding tire) while positive is directed in the other lateral direction (that is, in an axial direction of the corresponding tire). When referring to any lateral plysteer force, we are referring to at least the vector component of the force extending in the lateral direction of the vehicle or tire. With regard to the tire, this lateral direction extends in a direction parallel to the tire axis of rotation (which is referred to as an“axial direction”). These plysteer forces to be generated may be optimized for any particular conditions in which the tires are intended to be used, and therefore, it is contemplated that any these tires may be configured to generate any desired lateral plysteer force so long as opposing, free-rolling tires generate lateral plysteer forces in opposing directions. While the plysteer generated may act in opposing lateral directions between the free-rolling, opposing tire positions, it is appreciated that these opposing lateral plysteer forces may be of any magnitude, meaning, the magnitudes may be the same or different. When the plysteer magnitudes are substantially the same, it can be said that the opposing lateral plysteer forces are additive inverses of one another, that is equal in magnitude but directed in opposite lateral directions. When arranged on a crowned road surface, the magnitudes of the opposing lateral forces may be optimized such that the uphill side tire is able to overcome the combined effects of gravity and negative camber, but knowing that the plysteer already generated on the downhill side tire already at least partially overcomes the effects of gravity. Therefore, it may be that the plysteer magnitude to be generated by the uphill tire may be greater than the magnitude needed for the downhill tire in certain situations.

[0021] With regard to vehicles intended to operate along ground road surfaces having a crown. The road crown generates a downward slope, which may be linear or non-linear, across a width of the road, that is, in a direction perpendicular to a forward driving direction of the road. This downward slope typically is directed downwardly toward an outer side of the road, meaning, in a direction away from the one or more oncoming lanes. This is true even if a non-road median is present, separating the lanes opposing traffic. Therefore, for each lane of the road, the width of road surface extends from an uphill or high side downwardly to a downhill or low side of the road surface. Accordingly, when the vehicle is traveling in a forward direction in the proper legal direction, each of the opposing, free- rolling tire positions are arranged on one of an uphill side and downhill side of the vehicle, the uphill side being elevationally higher than the downhill side of the vehicle due to the slope attributed to road crown. In one example, when a single road surface includes opposing lanes of traffic are provided, the crown generally peaks at or near the road center or centerline. The road-center side of the vehicle is an uphill side of the vehicle intended to be arranged closest to a road centerline relative to an opposing outer road side of the vehicle when the vehicle travels in a forward direction. The tire position located on the uphill side of the vehicle is referred to as a road-center-side tire position while the other tire position of a pair of opposing tire positions is referred to as an outer-road side tire position. For example, when traveling in a forward direction of travel in a right hand lane of a road in a drive-on-the- right-side-of-the-road jurisdiction, the LH tire position is located on a road-center side of the vehicle and therefore is an uphill side tire position. In such instances, the RH tire position is a downhill side tire position. To improve tire wear performance on a negatively cambered uphill side free-rolling tire, a tire having negative plysteer is arranged in one of the uphill side or downhill side tire position and a tire having positive plysteer is arranged on the other of the uphill side or downhill side tire position.

[0022] Based upon the foregoing, a method of reducing irregular wear on a vehicle may be achieved, where the vehicle includes a pair of opposing, free-rolling tire positions generally located along a common rotational axis. The pair of opposing, free-rolling tire positions are arranged on opposing sides of the vehicle relative to a widthwise centerline of the vehicle, the first side configured to be arranged uphill relative to the second (downhill) side when the vehicle is traveling in a forward direction during vehicle operation. In certain instances, the method includes mounting a first tire to the vehicle in the first tire position and mounting a second tire on the vehicle in the second tire position, where the first tire is configured to generate a lateral plysteer force in a first (lateral) direction and the second tire is configured to generate a lateral plysteer force in a second (lateral) direction, the first direction being opposite the second direction. It is appreciated that the first and second directions may extend in directions of each tire’s rotational axis, may extend along the generally common rotational axis shared by the first and second tires, and/or may extend in directions towards and away from the vehicle widthwise centerline. It can also be said that one of the first and second tires is characterized as having a negative lateral plysteer force while the other of the first and second tires is characterized as having a positive lateral plysteer force, when operating under load during vehicle operation. When the first tire is to be arranged in an uphill side tire position and the second tire is to be arranged in a downhill side tire position on the vehicle, the lateral ply steer generated by the first tire (an uphill side tire) is directed in a direction away from the high side of the road surface and towards the vehicle widthwise centerline while the lateral ply steer generated by the second tire (a downhill side tire) is directed in a direction toward both the high side of the road surface and the vehicle widthwise centerline.

[0023] As suggested previously, the generation of plysteer (magnitude and direction) may be influenced by many any one or more tire design options, such as tread sculpture, conicity, product placement, belt angles, rubber compounds, rubber thicknesses, tread depth, belt wire construction, and cable size, for example. In particular instances, the desired plysteer is influenced by the angular orientation of reinforcements within an annular tire belt, which is more simply referred to herein as a belt. The belt is arranged radially inward from a tire tread relative to a rotational axis of the tire. The tire tread is also annular and forms the radially outermost portion of the tire and is configured to engage the ground and to provide traction for tire operation. Typically, the belt is slightly narrower in width than the tire tread. It is also noted that the belt generally is arranged radially outward a carcass that generally extend from bead to bead, such that the belt is arranged radially between the tread and the carcass, the carcass comprising one or more carcass plies each including a plurality of spaced apart, parallel elongated reinforcements arranged in an elastomeric matrix.

[0024] Each belt includes one or more belt plies, each belt ply including a plurality of spaced apart, generally parallel elongate reinforcements arranged in an elastomeric matrix, each of the elongate reinforcements extending lengthwise at a common average angle relative to the equatorial plane of the tire. These reinforcements may form any desired elongate reinforcement known to one of ordinary skill in the art and suitable for use in a tire belt ply. By way of example, these reinforcements may form a cord formed of any suitable material, such as steel or any other metal or any textile, such as aramid or fiberglass. These cords may be twisted as desired to obtain any desired property. As for the elastomeric matrix, any elastomer, including any synthetic or natural rubber, suitable for use in a tire belt may be employed.

[0025] It follows that in particular embodiments of the method described above in association with the first and second tires (that is, uphill and downhill tires), each of the first tire and second tire have an annular belt arranged radially inward from a tread relative to a rotational axis of the tire (belt has a width generally equal to the tread width), the belt comprised of one or more belt plies, where each of the one or more belt plies include a plurality of spaced apart, generally parallel elongate reinforcements arranged in an elastomeric matrix, each of the elongate reinforcements extending lengthwise at a common average angle relative to the equatorial plane of the tire. It follows that the plurality of elongate reinforcements of the one or more belt plies of the first tire are arranged to generate the lateral plysteer force in the first direction, and the plurality of elongate reinforcements of the one or more belt plies of the second tire are arranged to generate the lateral plysteer force in the second direction. This may result in at least changing the angular arrangement of reinforcements in any one or more of the belt plies. This includes the possibility of changing the angular arrangement of reinforcements in the radially outermost belt ply alone or in combination with changing the angular arrangement of reinforcements in any one or more additional belt plies within the belt of the uphill side tire relative to the belt of downhill side tire. In certain instances, the angular arrangement of reinforcements in all belt plies that are not low angle or substantially zero degree reinforcement belt plies is directed in opposite directions between corresponding belt plies relative to each opposing, free -rolling tire position. In other instances, all belt plies within a belt of the uphill side tire are altered relative to the belt of downhill side tire. In fact, in certain instances, the angular orientation of all elongate reinforcements in each corresponding belt ply between the uphill side tire and the downhill side tire are mirrored relative one another. In this scenario, the resulting lateral plysteer force generated by each uphill side and downhill side tire has approximately the same magnitude but is directed in opposing lateral directions.

[0026] While the belt may be formed of any quantity of belt plies, in certain instances the belt is formed of two belt plies while in other instances the belt comprises three belt plies, where in particular variations, a third belt ply is a low angle belt ply arranged radially inward and adjacent to the radially outermost belt ply. The elongate reinforcements in the low angle belt ply are arranged to form an angle with the tire equatorial plane between zero and 5 degrees (0° and 5°) or between zero and 3 degrees (0° and 3°), in absolute value. In certain instances, the average angle of the elongated reinforcements of a low angle belt ply is substantially zero, which is referred to as a substantially zero degree belt ply. By arranging this low angle belt ply next to the radially outermost belt ply, the radially outmost belt ply will provide greater influence over the plysteer generated by the corresponding tire. [0027] It is appreciated that each belt includes a radially outermost belt ply arranged closest to the tire tread. This radially outermost belt ply can be a significant influence on plysteer and the direction and magnitude of the resulting lateral plysteer force. In certain instances, to configure a tire to generate plysteer and certain lateral plysteer forces, the elongate reinforcements of the radially outermost belt ply are arranged to extend lengthwise in a direction biased to both the tire equatorial plane and the axial direction of the tire. This angle may form any desired angle to generate plysteer. In certain instances, however, to generate lateral plysteer forces that act in opposing directions between the opposing, free-rolling tire positions, the elongate reinforcements in the radially outermost belt ply extend lengthwise at a positive angle greater than zero degrees (0°) and less than ninety degrees (90°) relative to the equatorial plane for one tire to be arranged in one of said opposing tire positions while the elongate reinforcements in the radially outermost belt ply extend lengthwise at a negative angle greater than zero degrees (0°) and less than ninety degrees (90°) relative to the equatorial plane for the other tire to be arranged in the other opposing tire position. Quite commonly, in absolute value, each such angle is between 30 and 50 degrees, but this is only provided for example only. It is appreciated that depending upon the situation and usage conditions of the tires, these angles can be adjusted and optimized to improve tire tread wear. As noted previously, the angular orientation of the reinforcements in the other belt plies within each belt between uphill side and downhill side tires may remain the same or may vary between the tires. In certain instances the angular orientation of the reinforcements in all belt plies that are not low angle or substantially zero degree belt plies within each belt between road-center side and outer-road side tires are mirrored.

[0028] While reference has been made to two tire positions, namely, uphill and downhill side tire positions, it is appreciated that multiple tire positions may be arranged side-by-side on each opposing side of the vehicle. This contemplates, for example, trailers or dollies that employ a pair of tires on each side of an axle.

[0029] Reference is now made to the figures and the specific embodiments described therein.

[0030] With reference to FIG. 1, a loaded tire 10 is shown creating an area of contact CP between the tire tread 12 and the ground G, the area of contact CP being referred to as a contact patch. The contact patch CP has a length LCP, but the contact patch CP also has a width (not shown) extending across the width of the tire/tire tread. The shape and size of the contact patch is influenced by various factors, including the arrangement of elongate reinforcements within a belt contained in the tire 10.

[0031] Reference is now made to FIG. 2, showing a partially sectioned tire 10 exposing an annular belt 14 arranged radially inward (below) tire tread 12. The tire rotational axis is denoted as A. The belt 14 is formed of two belt plies 16i, 16 ₂ each having elongate reinforcements 20 arranged within an elastomeric matrix and extending lengthwise biased by an average angle oc20i, a20 ₂ relative to equatorial plane PE of the tire 10. It is noted that belt ply 16i is the radially outermost belt ply of belt 14. In overlaying the two belt plies 16i, 16 ₂ , the elongate reinforcements 20 from the two belt plies 16i, 16 ₂ form an overlaid X arrangement. It is noted that each average angle a20i _, oc20 ₂ may be any angle from 0 to 90 degrees, in absolute value, while in certain instances each average angle oc20i, oc20 ₂ is between 0 and 90 degrees, in absolute value, meaning, each average angle oc20i, oc20 ₂ is greater than 0 degrees and less than 90 degrees, in absolute value. As noted previously, these angles can be changed and optimized based upon the anticipated use and operating conditions to improve tire tread wear.

[0032] With reference now to FIG. 3, the tire of FIG. 2 is shown in cross-sectional form as taken along line 3-3 in FIG. 2. This figure shows the stacked arrangement of belt plies 16i,

16 ₂ in forming belt 14, which is arranged radially inward of tread 12 and radially outward of carcass 18 formed of a single carcass ply.

[0033] As discussed previously, the tire belt may be formed of one or more belt layers. In FIG. 4, three belt plies 16i, 16 ₂ , I6 ₃ are arranged to form belt 14. In particular, is it noted that the third belt layer I6 ₃ is a low angle belt ply arranged adjacent to the radially outermost belt ply I6 ₁ and between first and second belt plies I6 ₁ , 16 ₂ . This is also shown in FIG. 5, which shows tire 10 from FIG. 4 in cross-section as taken along line 5-5. As noted previously, the angle OC2O ₃ by which each elongate reinforcement 20 extends within the low angle belt ply

16 ₃ is 0 to 5 degrees, in absolute value, relative to the equatorial plane PE-

[0034] With reference now to FIG. 6, a situation where irregular or excessive tread wear occurs is more particularly described. In this figure, first and second tires 10i, 10 ₂ are mounted on a vehicle in opposing, free-rolling first and second tire positions Pi, P ₂ , respectively, and are generally arranged along a common rotational axis A on opposing lateral sides of the vehicle. In this situation, the opposing, free-rolling tire positions Pi, P ₂ are located on opposing ends of a solid axle 30, which connects the opposing first and second tire positions Pi, P ₂ . The vehicle centerline is denoted as CL _V . A load L is shown being applied to the axle by way of the vehicle to which it is operably attached. By virtue of the vehicle load L acting on the solid axle 30, the axle and/or the structure to which it is mounted deflects, inducing the creation of negative camber on each tire 10i, 10 ₂ arranged in each corresponding opposing, free -rolling tire position Pi, P ₂ . This negative camber is reflected by corresponding camber angles bi, b ₂ , which are measured relative to a plane P extending perpendicular to the ground surface G and the rotational axis A of the corresponding first and second tire 10i, 10 ₂ .

[0035] FIG. 6 also depicts the vehicle being arranged along a ground surface G forming a crowned road surface. The road is shown crowned across its width from the road centerline CLR by a constant angle 0RC, but this is only shown for exemplary purposes, as the road crown O _RC may be constant (linear) or variable (non-linear) across the road width. The crown is shown peaking at road centerline CLR. The road-center side of the vehicle is an uphill side of the vehicle intended to be arranged closest to a road centerline CLR. Accordingly, first tire 10i and first tire position Pi are located on the uphill side of the vehicle, where the first tire position Pi is an uphill side position. It follows that second tire 10 ₂ and second tire position P ₂ are located on the downhill side of the vehicle, where second tire position P ₂ is a downhill side position. In this example, the vehicle is traveling in a forward direction of travel in a right hand lane of a road in a drive-on-the-right-side-of-the-road jurisdiction, such that first tire position Pi is a left hand (LH) tire position while second tire position P ₂ is a right hand (RH) tire position. In the situation depicted in FIG. 6, the first tire 10i (a LH tire) experiences degraded wear performance due to the inducement of camber, which may occur whether or not the vehicle operates on a crowned road.

[0036] As noted previously, when operating the vehicle over the road, the road commonly includes a road crown. Due to the existence of road crown, which creates an inclined surface, the vehicle tends to be pulled down the inclined road surface away from the road centerline. With reference to FIG. 7, this downward pull due to road crown is represented by forces FRC, each of which act in the direction of the downwardly sloping crowned road surface (to the right for right handed traffic jurisdictions). Tires designed for over-the-road applications are designed to generate lateral plysteer forces acting in the uphill direction towards the road centerline to aid in counteracting the downward pull due to road crown. In FIG. 7, a prior art arrangement of first and second opposing tires 110i, IIO ₂ are shown, where the uphill plysteer forces are indicated as Fps. The prior art first and second tires 110i, IIO ₂ are shown partially sectioned, showing the radially outermost belt ply II6 ₁ and a radially inner belt ply II6 ₂ . As can be seen, the elongate reinforcements 20 in each radially outermost belt ply II6 ₁ extend generally in the same direction, while the elongate reinforcements 20 in each radially inner belt ply II6 ₂ extend generally in another direction, whereby an overlaid X arrangement is formed between the belt plies II6 ₁ , II6 ₂ . As noted previously with regard to FIG. 6, negative camber is also induced at each uphill side and downhill side tire position Pi, P ₂ . The forces acting on each tire 110i, IIO ₂ due to the effects of negative camber are indicated as F _(: . Because each tire 110i, 110 ₂ observes negative camber, each resulting force Fc acts inwardly towards the vehicle widthwise centerline CL _\ . As can be seen, there is an imbalance in forces observed by each uphill side and downhill side tire 110i, IIO ₂ due to the effects of negative camber, and regardless as to whether the vehicle is arranged on a crowned road - even though the vehicle is shown on a crowned road. Therefore, there is the need to provide a different uphill side tire 110i, that is, a tire intended to be arranged uphill on a crowned road, to improve the otherwise resulting degradation of tread wear performance due to the inducement of negative camber.

[0037] To improve tire wear performance on the intended uphill side tire, tire intended to be arranged in an uphill tire position is provided configured to generate a directionally reversed lateral ply force relative to the prior art uphill side tire. Again, this may be achieved in any manner. In particular embodiments, with reference to FIG. 8, it can be seen in comparison with FIG. 7 that the uphill side tire 10i in FIG. 8 has reinforcements 20 in each radially outermost belt ply I6 ₁ and radially inner belt ply I6 ₂ running in an opposite lateral directions relative to those reinforcements 20 in corresponding radially outermost belt ply II6 ₁ and radially inner belt ply II6 ₂ in uphill side tire 110i as shown in FIG. 7. The reinforcements 20 in each of the radially outermost belt ply I6 ₁ and radially inner belt ply I6 ₂ of uphill side tire 10i can also be said to run in an opposite lateral directions relative to those found in the corresponding radially outermost belt ply I6 ₁ and radially inner belt ply I6 ₂ of downhill side tire IO ₂ . Accordingly, in lieu of providing tires 110i, IIO ₂ having plysteer acting in the same direction (even if different magnitude), to improve tire tread wear in an intended uphill side tire 10i, opposing, free -rolling tires 10i, IO ₂ are configured to generate plysteer is opposite lateral directions - which may be of the same or different magnitude. In certain instances, for example, the lateral plysteer force magnitudes generated by each tire 10i, IO ₂ is 200 kgf but in opposing lateral directions. In certain instances, tire 10i generates a lateral plysteer force equal to or greater than second tire 10 ₂ or substantially greater than second tire IO2.

[0038] To the extent used, the terms “comprising,” “including,” and “having,” or any variation thereof, as used in the claims and/or specification herein, shall be considered as indicating an open group that may include other elements not specified. The terms“a,”“an,” and the singular forms of words shall be taken to include the plural form of the same words, such that the terms mean that one or more of something is provided. The terms“at least one” and“one or more” are used interchangeably. The term“single” shall be used to indicate that one and only one of something is intended. Similarly, other specific integer values, such as “two,” are used when a specific number of things is intended. The terms“preferably,” “preferred,”“prefer,”“optionally,”“may,” and similar terms are used to indicate that an item, condition or step being referred to is an optional (i.e., not required) feature of the embodiments. Ranges that are described as being“between a and b” are inclusive of the values for“a” and“b” unless otherwise specified.

[0039] While various improvements have been described herein with reference to particular embodiments thereof, it shall be understood that such description is by way of illustration only and should not be construed as limiting the scope of any claimed invention. Accordingly, the scope and content of any claimed invention is to be defined only by the terms of the following claims, in the present form or as amended during prosecution or pursued in any continuation application. Furthermore, it is understood that the features of any specific embodiment discussed herein may be combined with one or more features of any one or more embodiments otherwise discussed or contemplated herein unless otherwise stated.