Posts: 3472
Location: Elk River, Minnesota | Hiya,
I rotate each year from side to side. The reason....cupping on the edges of the tires.
Cupping is more pronounced on the front tires of rear wheel drive vehicles for various reasons, but mainly due to the scrubbing effect the tire has while turning,, coming into contact with the road surface...all combined with the normal bumping as it goes along the road, dampened by shocks.
Go to the front tires and run your fingers along the outside edge of the tire...you will feel it from front to back that each lug on the tire is uneven (usually lower in front, higher in rear of each lug). This is why on many vehicles, the tires swap sides when rotating from front to back, and the back tires come directly forward. The back tires have had a chance to level out going primarily straight for some time before being rotated back to the front.
On your trailer, the effect may be limited to some extent, but as stated above, the trailer takes a bunch of road bumping, so the axle might not be as "tight" for alignment, which can increase the "scrubbing effect" as the tires travel down the road. Rotating from side to side will help reduce excessive wear. In many cases the wear on a trailer tire goes diagonally across the entire tread when allignment is off (toe in or toe out), and either the inside or outside if the tire is not perfectly upright, cambered in at the top creating excessive wear on the inside edge of the tire.
Inside edge wear will not be reduced by side to side rotation unless it is only on one side (usually due to hitting a nice pothole somewhere).
Steve |
