Trailer Tires with Inside Wear on Boat Trailer

Question:

2005 single axle Bear boat trailer Inside wear low miles New axle and hubs last year. 165f g3 Yamaha. 2005 boat being carried 3500 axle

asked by: Eugene L

Expert Reply:

There could be 2 causes of the abnormal wear on the insides of your boat trailer tires; the most common is an overloaded trailer. The other potential cause is an improperly installed or bent axle.

Since this is a new axle, and it sounds like this problem has just surfaced since it was installed, I would make sure that the new axle was installed properly. Trailer axles will all have a bit of a bow to them, to compensate for the lack of adjustable camber. When installed, the bow should be facing up (as shown in the picture) which causes the outside edges of the tire treads to make first contact with the ground. This allows for when the trailer is loaded with weight the axle will be pushed downward to a flatter position with the tire treads level on the ground. Since the wear is occurring on the inside, something leads me to believe that either the axle is bent or was installed upside down.

You'll want to check this with an unloaded trailer, and stand at the back of the boat and see which way the axle bend is facing. If it's facing up, as shown in the picture, it is installed correctly. If during inspection you've noticed that the wheels/tires are NOT tilted slightly outward at the top but the axle is installed properly, you may have bent spindles that would need to be replaced. If everything checks out with the axle, check the sticker/plate with the trailer load ratings and determine what the GAWR/GVWR are and whether or not that trailer is properly rated for your boat, since an overloaded trailer would be the only other logical explanation for this situation.

Once you get this sorted out, if you're currently running Load Range C tires like the Loadstar ST205/75D15 # AM1ST92 you may want to consider going up to LR D or even E, to give yourself something with a little bit stiffer side walls; this would give you a little added security for when you've determined that the trailer isn't going to continue to wear through tires unevenly.

expert reply by: Erik B