Can ST225/75R15 LR E and ST225/75R15 LR D Tires Be Mixed On Triple Axle Boat Trailer?

Question:

I have a tri-axle boat trailer with 225/75R15 Load D on all three axles...The third axle always carries some extra weight no matter how hard a balance my load...the boat is a twin I/O so its heavy in the stern already...Id like to put some higher capcity 225/75R15 Load E on that third axle just to add a little extra safety as the nitrogen has better pressure consistency... and maybe going forward replace all the tires with E rated nitrogen...THoughts on this approach?

asked by: Ken

Expert Reply:

It sounds like you have a solid plan.

The ST225/75R15 Load Range D tires you currently have on your triple axle boat trailer have a 2540lb load rating at 65 PSI where the Provider ST225/75R15 Radial Trailer Tire - Load Range E # TR225LRE, which are - load range E like you mentioned have a 2830lb load rating at 80 PSI. You would just need to choose a 15 inch wheel with a 6 on 5-1/2 bolt pattern like the Silver Mod Lionshead Wheel # LHHA312 or use your existing wheels. You can get them mounted at a local shop and they can add nitro if you wish.

Putting these tires and wheels on the rear axle will give you extra support and will not cause any issues with the front two axles having lower rated tires.

You will just want to make sure your bolt pattern is 6 on 5-1/2" . You can confirm this by using the included help article to measure your current wheels.

Moving to Load Range E tires all the way around would fine also should you decide to spend the extra money. The only real benefit you will see is the tires will run cooler as you would be using them well under their maximum rating, and since heat is the main enemy of tires you would get longer tire life.