Dear Gary,
It seems lately that my travel trailer tires are wearing unevenly side to side. Measured to ground, the side with the most tire wear is about 3/4 inch lower than the other side. This is after replacing all the tires and checking inflation. I then weighed both sides of the trailer and found that the side with the most tire wear was about 500 pounds more. This is the side where the refrigerator is directly over the tires. We presently have over 15,000 miles on the trailer. Is there anything we can do to make the trailer level? I know because of the design there is little that can be done to equalize the weight side to side. —Jim
Dear Jim,
First of all, congratulations! You are well on your way to better balance and longer tire life simply by becoming aware of weight and balance issues.
One question I have is: How was the 500-pound difference determined? The only way to determine the left–right loading is by individual wheel scales (per NHTSA). Without individual load measurements we’d only be guessing and may not pinpoint the correct fix for your issue. Weighing RVs on a flat (platform) scale has proven to be inaccurate at best (again by NHTSA). Using individual scale readings is the only way we can determine the exact cause of your issue, since every RV is different.
I need to ask if the heavy side is exceeding a tire rating or the axle rating? This would necessitate a more aggressive action if so.
I would look for items I could move to help the balance. Every little thing adds up, and remember, just 50 pounds going to the other side equals a 100-pound difference: -50 pounds on one side and +50 pounds on the other, and we are now 100 pounds closer to being balanced.
The RV Safety & Education Foundation recommends inflating trailer tires to the sidewall inflation pressure unless we have individual wheel position weights to work with. A 1-inch difference in ride height on a trailer is not very much, considering the big picture, but simply adding a band-aid to make the unit level will not cure the load issue. The heavy side will still be the heavy side though it may appear to sit level.
Another cause for the difference could be what’s called “spring sag.” When vehicles remain loaded over a period of time, the springs will take a “set” and the heavier side would be more dramatic than the lighter side. With a trailer that has had a 500-pound higher load on one side for several years and many miles, you can probably understand the consequences. This is, however, not a difficult or expensive issue to address: Simply install new springs. Just be sure the shop is reputable and installs the proper-rated springs.
Balancing the load and having the correct inflation pressures will have the most positive effect on tire wear; however, all the issues you bring up will contribute to uneven tire wear.
Read more from Gary Bunzer at the RVdoctor.com. See Gary’s videos about RV repair and maintenance.
##RVT902
