Recommended ST235/80R16 Radial Trailer Tire for Highway Use

Updated 06/29/2016 | Published 06/28/2016

Products Featured in This Question

Karrier ST225/75R15 Radial Tire with 15" White Spoke Wheel - 6 on 5-1/2" - Load Range E

(1522)

$218.25

Provider ST235/80R16 Radial Trailer Tire w/ 16" White Mod Wheel - 6 on 5-1/2 - LR E

(1135)

$270.47

Question:

I am looking for information on what tires and wheels to purchase for my Raptor toy hauler 5th wheel. Here is my situation: The trailer weighs about 15500 pounds wet and loaded. It has three axels each rated at 5080 lbs. Its GVWR is 155000. It is 33’ long and 102” wide. I do not know the per axel weights or the side to side weights. I have been running Carlisle Radial Trail ST225/75R15 load range E on 15” aluminum wheels. Air pressure cold 80psi. I have a blow-out at least once each trip depending on the length of the trip. The last one took out a good portion of the sheet metal skirt. The axels are approximately 33” on center. With the existing Carlisle tires, that leaves about 4 to 4.5” between tires. With a diameter of 28.5” there is approximately 4.5” clearance from tire top to under side of the trailer. Lots of room left and right of the wheel well. The wheels are 6 on 5.5”. What I would like to do: I would like to get a tire with a load rating of at least H and not less than G. I’m pretty sure I will need to replace the 15” wheels with something larger – 16” or maybe 17.5” – if I can get tires with a diameter that will fit the axels. I will need eight tires and wheels, six running tires and two spares I’ve been burned too many times. I am looking for your recommendations on tire and wheel combinations. And any other suggestions you may have to solve this problem. Wheels can be plain and inexpensive as long as weight and pressure rated . Thanks.

asked by: Ben O

Expert Reply:

The highest load rating 15-inch wheel/tire combo we offer in your 6-on-5-1/2 bolt pattern and ST225/75-15 tire size is a Load Range E, the same as what you have currently, Kenda part # AM32680. This is rated for 2830-lbs at 80-psi. This wheel/tire has an overall diameter of about 28-1/2-inches as you noted.

Since you have ample space above the tire and around the inner side, you can switch to a higher-capacity 16-inch wheel/tire like the Provider ST235/80R16 Radial Trailer Tire # TA39VR. This item offers the same bolt pattern on its 16-inch rim and the load capacity is a hefty 3520-lbs.

The diameter of this tire size is about 30.79-inches, which means you'd lose about 1-1/4-inches of clearance between the top of the tire and the trailer. This will still be enough clearance. Please note this tire carries an M speed rating of 81-mph maximum, making it ideal for interstate highway travel.

Please note that the most common causes for tire blow outs are incorrect inflation pressure (either under- or over-inflation) and exceeding the tire's speed rating. All of these things will cause the tire to overheat, and heat is the enemy of trailer tires. Be sure to always inflate trailer tires to the specified cold pressure shown on the sidewall and to avoid driving over the tire's speed rating. Unless indicated otherwise, all trailer tires we sell are rated for 65-mph.

expert reply by: Adam R