need help picking tire size

[vardenafil]

I have a 1972 k20 with a 4 inch lift all around. I just bought some new rally style rims for the truck. the rims are 20x9 with -12mm offset. I would like to get 33 inch tall or possible slightly bigger tires for the truck if possible. my dilemma is that no local tire shops will test fit tires on the truck. and i cant return them if they dont fit. i dont want rubbing or to have to trim the fenders if possible. Im looking at 305/55r20 or 275/60r20 tires. will these fit? the tires on the truck now are 7.5r16 (31.8 inches tall?) there is about 4.5 inches from the tire to the fender. im worried about rubbing when the wheels are turned

[GSP7]

Get US Mag 101s, 17x10 and some 35" tires

https://www.summitracing.com/parts/usm-u10117008245





20" are too big

[57taskforce]

The US mags are nice wheels but Why would he buy new wheels if he already has bought what he wants? A 20” rally could be pulled off well on these trucks I believe. 33X12.5 won’t rub, 35x12.5 will likely rub when articulated around a bit. I’ve got 315x75x16’s (34.5x about 12.5) on my 4” lifted K20 and they do rub a little bit from time to time but not in normal driving conditions. It’s always when Ive got the truck twisted up a bit. I’ve got 1” zero rates in the rear and I’m going to add a set to the front to rid myself of the rub. By the way I love that truck OP!

[jumpsoffrock]

Ya them 20's are gonna scream "mall crawler". But you already bought 'em, so thats a tight spot to be in.
You best bet is to find the exact dimensions of the new tires on https://www.tacomaworld.com/tirecalc...0r15-235-85r15

Then find what tacoma world has to say about the tires that are currently on your truck, and compare similarities and differences. That should hopefully tell you if you'll having rubbing issues.

[Richard]

Agree with what 57taskforce said. 33's will not likely rub in normal use. 35's will absolutely make contact with wheeling unless bump stops are lowered or fender clearanced. Been there, done that. The -12 offset wheels will put the tires just inside the top edge of fender well as long as you do not go real wide with the tires. The shorter sidewall with the 20" wheels on the 33's will definitely make the ride a bit firmer. No worries, run what you want.

[MikeB]

Why not use the same height tires as you have on the truck now, or do you want something taller? Looks to me like you could go another 1" taller. By "taller" I mean overall outside diameter.

I'm surprised a tire shop won't let you try different sizes if you commit to buying from them. I suspect that's been done by many of us over the years.

[vardenafil]

I want to go a little bigger because the current tire size looks too small for the lift. I want to fill the wheel well up a little more. this is the look i am hoping for. I saw a similar set up to that with 33's and it looked good. im going to call around and see if i can find a shop willing to test fit tires for a few bucks.

[vardenafil]

Originally Posted by 57taskforce

By the way I love that truck OP!

Thanks. First complement Ive gotten. Ive almost buttoned up all the mechanics for the truck. I got a few things left... Then im going to start with the body work and interior.

[Orefactory4x4 swb]

Personally I would go somewhere like 33s
I’ve regretted 35s every time, with not enough lift they always seem to rub somewhere.
But, if you drive it around like a dropped c10 you’ll probably be ok with 35s
Dig the truck, post pics when your done.

[Jason Banks]

what size tire is that in your original picture?

[RichardJ]

Speedway sells a fully adjustable test fitting jig for checking tire clearance. You could make up something like that out of sheet metal or 1/8" plywood to test for the tires you want to use. With jacking of the suspension at various points, you should be able to get a good idea of what will fit.
https://www.youtube.com/watch?v=m4nGR6kWeUI