What backspace to run these wheels 15x8/15x10

[HeloCrewChief]

I have a buddy at work that thinks the stance/wheels/tires are perfect on this truck. I have to admit it looks pretty good. I know this much about it, "4/6.5 drop with 8" front/10" rear wheels and 235/70/15 front -285/70/15 rear tires" from some digging I did on the forum. Question is, what kind of backspacing do you have to run to fit those wheels and tires? I'm guessing 5.5" backspacing on the back or is it 5"? How about the fronts? My coworkers truck is a 1972 C10 short bed fleetside with factory disc brakes and dropped spindles.

[SkidmoreGarage]

It is hard to give you an answer with enough credibility to confidently tell you to spend at least a couple grand on wheels and tires. There is a lot of variability between individual trucks.

If you have the narrower 63-70 rear end, you will want about 4.5" backspacing on a 10" wheel, in my experience, to get the tire to fit like in the photos. For the later model axle, 5".

For the front, you can use a calculator to get a matching track width for the narrower wheel.

While common, there is little benefit to running that big of a wheel stragger front to back and a number of downsides. You can always run wider tires front or back. On a 9" wheel, you can run a 225 on up. This may open up your options for wheels, given there limited number of sizes for each brand on the shelf.

[HeloCrewChief]

I think he just likes the staggered Hot rod look with the deep dish on the back. I knew the axles were different widths. Just seems like the margin for error is very small. Wheel vintiques makes the wheel in a 15x10 with 5" backspacing off the shelf. They can obviously be built in any backspace. I'm sure someone out there is running this set up and knows for sure.

[lolife99]

A 15” wheel up front can’t run more than a 4” backspace in my opinion.
Even at 4” bs you will probably be trimming the lower a-arm with a drop spindle.
I actually own a custom set of 15x8 rally wheels with a 5” backspace. They won’t work up front.

Also watch your total tire height with that much drop and stock inner fenders.
I suggest lowering first. Then measure for wheels.

[basketcase]

My fronts are 15x7 rally wheels with a 4" backspace. 2.5 spindles and 2" springs needed to polish off some of the lip on the lower control arm but not much. Anything more with this drop and a 15" wheel would be a major interference problem

[young grasshoppa]

I run 15x8 (245/60/15) up front and 15x10 (275/60/15) out back, both with 5" backspace. My drop is an ECE 4/5.5. I like the look of the 7-series tires you posted, I wonder how that would fit my truck.