Biggest rear tire on a C10

[JKady]

Wondering what the biggest/widest rear I can run on my '70 is before the frame starts to interfere? Basically want a pro-street look without having to rebuild the whole rear of the truck since it's my daily driver and I like how it drives. Planning on a drop to be decided after I get the tires and wheel package under the truck. I'm running 31x10.5 now and they've got a lot of room, but big big street tires aren't something I can just run down and grab from the local used tire guy so I would like to know what fits before I go dropping coin on new shoes.

[70cst]

ttt

[68Stepbed]

The frame interference isn't the problem, it's the wheel tubs. Do you have a stepside or fleetside? Are you lowered any, or plan to lower it any? What size (dia) wheel do you want to run? These are important questions that need to be addressed before any real answers can be obtained.

Check out Hart Rob's 6T8ZZZ farm truck build. It's slightly tubbed with widened stock wheeltubs, and it's been through several sets of wheels before it's current 18/20 combo. That might help with an idea of what may fit.

[hgs_notes]

I used to have 295-50-15's on the back of mine. It was lowered with springs 3.5" and no other mods. The tire on one side would rub the wheel tub in turns with body roll. It was probably off center by about 1/4".

For a really fat tire you have to cut the bed and widen the wheel tubs.

[JKady]

Thought I had all that in there but I guess I left everything out re-wording my original post. '70 fleetside. Want the biggest tire I can fit after tubbing. Like I said, drop will come after my wheel/tire package is set

[RexDodge]

I think what Matt was saying is good advise. Before picking your tire wheel combo you need to decide on the amount of drop you want. The inner wheel wells slant in at about a 45 degree angle a bit before they go up on these trucks. You'll need to consider that when you fab your new wheel wells. Without changing that you're going to look like the guy in hi school that slaps air shocks on and some big tires (no disrespect intended to anyone). To pick a wheel or at least start the planning process I would suggest you take some measurements. Figure out how much back spacing you can get by re-working your wheel wells. Measure from the face of your drum/axle to the back of the wheel well (or the point you intend to widen it to) and then do the same for the front spacing. Take a couple of inches off that measurement and that would be the maximum width you can run with not hassles. Remember..you need to "modify" that outer lip or you'll rub. Many wheel manufacturers have options for back spacing. If you want that "pro street" look you can make your tubs wider (takem to the frame) and order a set of wheel with the maximum back spacing allowable for your application and that will move the wheel to the inside. Get yourself some drag radials and your stylin...start measuring and have fun. Do a search on this site and I'll bet someone has done a write up on a similar project.

[68Stepbed]

Yep, you're getting your cart in front of your horse. You need to decide on the drop you want first, then decide on wheel/tire setup. Actually, you need to decide both at the same time.

[Ackattack]

I'm on airbags, so probably 4-7" drop depending on where the bags are set. I tubbed the rear wheel wells and my wheels set the tires ~1/16" from the inner wheel wells at full dump. They are 315/35/20. I have about 2" or more on the inside of the wheelwell.

[JKady]

How about we pretend for a moment there are no wheel tubs if that'll help, I have a sawzall, I can put the tubs where they need to be after the fact. Sheet metal is very mobile, ask anyone that's watched me put 33-35" tall tires on a stock height rig. Lets just throw 4" out there as the max I'll drop the thing.

[1968ratrod]

14 or 15 inch wheel and about 18.50 tire with the right offsets.........

[QKENUF4U]

with tubs you can fit a 31x18.5 on 14" rims w/ 10bs.. wont touch a thing... good luck getting them balanced though (wont fit on tire machines) you could bubble balance them though...

[JKady]

NICE! Any more pics or a build thread?

[mike hancho]

I'm running 295/65/15 stock Stepside. 15x10 with 4 inch backspace. Fits perfect
Posted via Mobile Device

[darkhorse970]

Originally Posted by mike hancho

I'm running 295/65/15 stock Stepside. 15x10 with 4 inch backspace. Fits perfect
Posted via Mobile Device

What brand tire is that? Can you post pics?

[LEX]

This member ran a 28x13.5x15

[Hart_Rod]

I'm running a 31 x 16 tire on a 20 x 12 wheel. The only thing that is done to mine is widened wheel tubs.

[mike hancho]

Mickey Thompson et street
Posted via Mobile Device

[70blackfish]

Anymore pictures?

[codeJbird]

I have 20x14's w/ a 29x18 wide tire. tubbed of course, no frame work

[jst4fun]

i see this is an older thread but was wondering what offset the guy with the 20x12 has as I am looking at doing them for my 72 c10 swb

[70blackfish]

I installed wider tubs, and 29/15/15 M/T tires

[jst4fun]

I am thinking I am going to be tubbing mine as well. Really want to go with 20x12 rims on the back as i will be dropping a 572 and a t56 magnum 6 speed in with a dana 60. Just was curious what backspacing hart rod had on his.

[Theboatandcarman]

I am shooting for 315 wide on the rear of my c20 fleetside. Looks like I'll need around 5" back spacing?

[71threequarterton]

Originally Posted by Theboatandcarman

I am shooting for 315 wide on the rear of my c20 fleetside. Looks like I'll need around 5" back spacing?

Sorry I can't directly answer your question but I plan on running Wheel Vintiques 16x10 w/ 5" backspace and most likely a 305 70 r16 tire on my 71 C20 fleetside.

I will pull the current wheel off and try the 16x10 wheel on before I get tires mounted, just to make sure the backspacing is right. This is on the REAR ONLY.

I am curious to know how a 315 fits on a C20 fleetside. What will your exact tire size be?

[Theboatandcarman]

Originally Posted by 71threequarterton

Sorry I can't directly answer your question but I plan on running Wheel Vintiques 16x10 w/ 5" backspace and most likely a 305 70 r16 tire on my 71 C20 fleetside.

I will pull the current wheel off and try the 16x10 wheel on before I get tires mounted, just to make sure the backspacing is right. This is on the REAR ONLY.

I am curious to know how a 315 fits on a C20 fleetside. What will your exact tire size be?

I'm shooting for 315/35r20! I'm only dropped 3/5" so it should be clear, I'm gonna have to Re drill a tire/rim fitment gauge for 8 lug