Rear Wheel width

[Chevyc10572]

What is the widest wheel you can fit on the back. I’m lowered 6in in the rear I found a set of wheels on Facebook market place and thought 20.10.5 would work.

[GASoline71]

You can go fairly wide with the correct offset.

Gary

['70_402]

4.5 bs you can fit a 295 on a 10" wheel.. that's max for a 1968 anyway..

i know the later years had a different width rear end.

[HO455]

You need to verify which axle width to be sure of the back spacing needed.
Since you are lowered you will need to have a long adjustable track bar installed to center the axle at ride height.
Good luck with your purchase. If they're local drive over and do a test fit.

[CC69Rat]

Fleetside or stepside?

[Joyridin]

If it is not lowered, 12" is possible but very tight. If it is lowered, then 10" is probably max. The inner fender arc is pretty fast, so when you lower it, and assuming you give it 2-3" of float, your wheel will have to not be as wide.

I installed 2" wider tubs. You don't really even notice the extra width like you do on the 4" wider versions. With that, my actual tire width is 13.8".

[Chevyc10572]

Originally Posted by CC69Rat

Fleetside or stepside?

Fleetside

[CC69Rat]

As mentioned, the first thing you want to check is what Rear end housing is in the truck now. 63 (earlier?) - late 70, these trucks had a slightly more narrow housing in them than the later years. The only real way to know is to measure it. 5 or 6 lug doesn't really tell you much. It may have been swapped at some point in its life (?) Just saying I'd measure it.

The easiest way I know to do it, is just lay under the back of the truck. Have your wife, buddy, whatever hold one end of the tape against the back side of the rear brake backing plate. (Assuming drums on the back?) Measure across to the other side in the same spot. If it's roughly 57", you have a later rear end housing. If it's 55.5", it's an early housing.

So, with this in mind the rear housing width can make .75" difference per side, and if the truck is really low it could mean the wheels fit, or.. they don't. Not all the trucks are the same and if you don't have an adjustable track bar on it, I too would suggest one. It will even up the axle housing side to side. That way you're not rubbing on one side, and 2" clearance on the other.

We just need to know which housing you have, and I can make some suggestions for you from there.

[1967-C10]

11"maxium on (stock setup Frame/wheelwell) with aftermarket wheels.
fitting inside the wheelwell.

[Accelo]

I have enclosed some pictures of 275/45R20 on the rear of the 1970 truck that is lowered 4 or 5". Wheels are 10 X20's and have zero offset. I don't see how one could go any wider, with stock wheel wells, without some issues.
Certainly no room on the inside. The outside may have a little room but that would depend on the profile of the tire and how low you are.

[Thealien]

This is what we are doing for a little bit more room.

[Accelo]

That sir, is some really nice metal work.

[Joyridin]

Originally Posted by Thealien

This is what we are doing for a little bit more room.

That looks nice! I think that would have given me about an extra inch on the offset or width.

[Thealien]

Originally Posted by Joyridin

That looks nice! I think that would have given me about an extra inch on the offset or width.

That’s what we figured about an inch gained. On a blazer there’s not much room between the rear seat and the wheel tubs so I don’t have a lot of options to run a wider tire. My fabricator is pretty good though he did those way better than I had anticipated.