The Stovebolt Site Forums The Shop Area Engine Shop 235 85 R16 on a 1/2 ton?

I'm considering replacing the tires and wheels on my '55 2nd series 1/2 ton. Stock wheels are 15" and have 235 75 R15 tires mounted.

I'm considering buying 16" wheels and mounting
235 85 R16 tires on them. I like them for 2 reasons. First, I like the look; it's like the truck is wearing boots. Second, the larger diameter will help at higher speeds.

Here are my questions.

1. If I buy 16" x 7" width wheels, I think I have to order them with a 3.5" backside spacing (this is the horizontal distance from the brake drum surface where the wheel contacts to the tire bead on the inside). I suspect 4" spacing is too much and can cause the tire to rub on the tie rod end. Can anybody confirm?

2. Will 235 85 R16 tires fit within my wheel wheels without rubbing on anything? The diameter of the tire is about 32". That's 3" more than the 235 75 R15 tires that I have now.

Thanks,
LT

LT,

Have you check the diameters for other 15" tires? You might be able to find a 31-32" diameter 15" tire.

I do not have an answer about backspacing (wheel offset ?) or maximum diameter; but, on earlier 1/2 and 3/4 ton trucks, the offset ranged from 0" to 9/16" and the loaded tire diameters ranged from around 28" (15" and 16" inch rims) to around 31" (17" rims on the 3/4 ton).

My guess is that the diameter will be no problem but the 4" backspacing/offset might be a problem

Maybe someone with first-hand experience will respond.

Tim

I don't know about the 1/2 Ton, but the 1 Ton has a backset (not offset) of around 3". You can't put a 4" backset on a 1 Ton.

There are really huge tires that you can get for 15" rims, but they are really wide, and they require wide rims. The offroad people use them.

They also sell a 255/85R16 tire which gives you an even larger diameter. I think that I will use them on the back of my 1 Ton. It is a flatbed, that is with no rear fenders.

While I was thinking the steering rod was moved to the front on the second series, I will give you what I know based on the first series with the steering rod aft of the front axle.

You're right on the setback. I would get the tire size dat of both your current tire and the new tire from Bridgestone Tire . Then crawl under the truck and measure to see where you are and will be. The 16" wheel will be 1/2" more radius than the 15, check this in relation to the tie rod end, too.

I don't know what you're getting for rims, but you might want to consider going with a little less backspace. As for tire clearance to the fenders, I think you'll be okay. I mocked up some 7.50R-16 on my 3/4 ton front end, and came up okay. Tire is about the same diameter as what you're looking at, but a bit narrower.

Anywhere you can buy locally? If so, they should be able to help you a lot on the fit of the tire and wheels. Also, don't be afraid to put taller tires on the back than on the front. That way you're always running downhill, so you can save some gas!