Stock rims with 35/12.5/15s

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Stuka
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

Sorry I missed that. The center bore for a hub centric wheel should be 3.5", and I went out and measured the hub centric wheels on my truck to verify. 4.25" is what a 3/4 ton (8 lug) would use.

but a lot of after market wheels do have the larger bore, which means you need to use hub centric rings to prevent vibrations.
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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

Oh good now it makes sense. I'm guessing the rears are lug centric

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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

I found 2 used sets that will fit. Aluminum with 3.625 backspace and chrome with 4.3/8 backspace. Opinions?
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

No, they are hub centric too. The center of the axle flange is raised and is the same diameter as the front.
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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

Hendo2.5 wrote:I found 2 used sets that will fit. Aluminum with 3.625 backspace and chrome with 4.3/8 backspace. Opinions?
any thoughts on these choices? The chrome seems to have a deep backspace but are less expensive. either set would need to be cleaned up
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

If you had a Cherokee, I would say either would work. But with you have a J-Truck, over 4" of BS with 12.50's won't work for you.
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

A photo as an example. 33x12.50 with 15x8 K10 Rally wheels.

ImageImage


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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

Thanks for the pictures. That actually looks pretty close. Are those the rims with the 3.75" backspace?
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

These are GM K10 Rally wheels which have 3 5/8" backspacing.
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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

I found some old GM 15x8 aluminum rims that have that same backspace. except for the age I think they look good, sort of like Mickey Thompson classic III's but not quite as nice. I don't know what the offset is but the back space is 3.625/ centre bore is 4.25 which is quite a. gap but I found spacers on line. should I be okay to run the 35/12.5/15? thanks
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Re: Stock rims with 35/12.5/15s

Post by tgreese »

If you know the backspacing and the wheel width you know the offset. An 8" wheel with 4" backspacing has zero offset. So a 3.625" backspacing is a -0.375 offset. A 10"wheel with the same backspacing has a -1.375" offset.

Can't comment on whether you need the hub-centric wheels.
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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

I found some 15x8s with 3.75 back space and mounted my 35s on them. They are way too close the suspension for comfort. Any thoughts on spacers?
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

How close are they? Unless the wheels are bent, or something bad happens, if you have clearance, they should always clear. I have been driving my truck for almost 13 years with 12.50 wide tires on the same wheels.

Wheel spacers will push the tires out 1.5 inches, and the rear axle is already wider than the front. I am personally very against wheel spacers, seen way to many of them fail.

If they are indeed too close, you will need to find some 15x10's, which will pull the tires out more. That, or move the springs under the frame.
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Re: Stock rims with 35/12.5/15s

Post by Hendo2.5 »

is there any reason a 35 would stick out further than a 33 assuming 12.5/15?
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Re: Stock rims with 35/12.5/15s

Post by tgreese »

Depends on the design of the tires. If the cross-section width is the same, the bulge will be the same. However, in general, a taller tire will have a larger cross-section even if the tread width is the same.

The tire manufacturer has specs. Look them up.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
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Re: Stock rims with 35/12.5/15s

Post by Stuka »

Yeah, 35x12.50 is more of class of tire. Some are wider, some are narrower. I have run 33x12.50 TSL’s and Cooper STT on my truck.

BFG’s are known for being undersized for instance. While Maxxis is known for being very true to size.
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