Can I Move Up to a 12 Inch Wheel From an 8 Inch Wheel on a Vintage Boat Trailer

Question:

vintage tandem boat trailer has 5.70x8 tires and rims with a 31/4 center hole 5 lug.would like to replace the four.gross weight 2200lbs. could move up to one of your 12 inch wheels and tires sets with the 3.19 center hole. would this work

asked by: Lyle C

Expert Reply:

You can move to a larger wheel and tire as long as you have enough room in your fender well between the wheels of both axles, between the inside of your wheels and the trailer frame and from the tire tread to the inside of the fender. You will also want to be sure that you choose a wheel that matches the bolt pattern of your hub. I would guess that your bolt pattern is 5 on 4-1/2 inches, but it is important that you measure to be sure. I have attached a help article on determining your bolt pattern for you to check out.

Another factor to consider is whether your wheels are lug-centric or hub-centric. This will determine the size pilot hole that you will need for a wheel. Lug-centric wheels will center on the hub using lug nuts and the pilot hole of the wheel will have to be greater than or equal to the hub bore. If your wheels are hub-centric, then they will center on the hub bore and use wheel bolts to attach to the hub. If your wheels are hub-centric, then you will need to find a wheel with the same size pilot hole. We do not have a 5.70-8 wheel with a 3-1/4 inch pilot hole.

The recommended clearance between the top of your tire and the fender should be no less than 3 inches under a full load. You will want to measure your current tires and wheels to make sure you will have enough room when you upgrade to a 12 inch wheel.

You will also need to consider the space you have available between the tires on each side. It is recommended to have 4 to 5 inches between the tires on the same side on a tandem axle trailer. If you have a 5 on 4-1/2 inch bolt pattern, then you could look at the Kenda 4.80-12 Tire and 12 Inch Wheel, # AM30660. This wheel and tire has an overall diameter of 20.7 inches, which is 2.7 inches larger than your current tire and wheels.

If you go with the 4.80-12 tire, then it will not be wider than your current wheels so you should not have to worry about clearance between the inside of your tire and the trailer frame.

If you determine that moving up to a 12 inch wheel will not be feasible due to clearance issues, then I would recommend measuring the center bore of your hub. We carry 5.70-8 tires and wheels with a 5 on 4-1/2 bolt pattern that have a center pilot hole diameter of 2.8 inches. This is the largest pilot hole diameter that we have for an 8 inch wheel.

expert reply by: John H