Widest tire using stock 15x8 rallies

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Scruffy49

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And yes, that was a test fit, flip kit rear hole instead of front hole. That 1/2” in the bracket really does make that much difference on wheel/tire position.

Ralph (truck) is a sorta kinda test mule. If you are still working on your truck, just use the front hole in the bracket. Me being me, had to see it for myself. Since it doesn’t run, and won’t until I pull and rebuild the engine, no harm no foul. Driving it with the axle too far forward risks: U-joints, output shaft, tailhousing, pinion yoke/seal, driveshaft.
 

Ricko1966

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Before anyone pics what hole to use based on a visual. More importantly which position makes the driveshaft the right length. Fine and good to center the wheel,but check driveshaft length.
 

Scruffy49

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Before anyone pics what hole to use based on a visual. More importantly which position makes the driveshaft the right length. Fine and good to center the wheel,but check driveshaft length.
I’ll take another pic sometime during the build, using the front (recommended) bracket hole. Using the rear one pushed the axle into driveshaft bind territory. Almost imposdible to actually get the axle reseated on the locator peg.
 

Scruffy49

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Reset to the front mounting hole. Still not visually centered, but the driveshaft has full movement. Still wearing P235/75r15 108XL rear tires. Rear flip, shock relocators and Gabriel Load Assist shocks. With standard shocks it sits 3” lower than in the pic, limiting it to a 28” tall tire.
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Gander

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You know, I’ve never understood why the stamped steel rally wheels are 15x8 but the optional aluminum Budd looking wheels are only 15x7. Anyone know what the logic was behind that decision? I love the fact my truck has the optional aluminum rims but it came with 31” inch tires from the factory and am I wrong in thinking that’s just about as big as I can go on them?
 

Turbo4whl

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Still don’t get it. Why would you want to put a lowered truck on skinny high profile off road tires?
Larger wheels change the scrub line. That rule is current in Pennsylvania for modified vehicles. "no vehicle suspension parts or frame can be below the scrub line."

Scrub line? Who knows what that is? :)
 

Scruffy49

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Larger wheels change the scrub line. That rule is current in Pennsylvania for modified vehicles. "no vehicle suspension parts or frame can be below the scrub line."

Scrub line? Who knows what that is? :)
With the cute little 15s, still nothing hanging below the edge of the backing plates… ;)
 

Grit dog

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Larger wheels change the scrub line. That rule is current in Pennsylvania for modified vehicles. "no vehicle suspension parts or frame can be below the scrub line."

Scrub line? Who knows what that is? :)
I had to look it up.
Maybe that’s a thing enforced east of the Mississippi. Kinda like lifts, bumper height, tire poke, truck and trailer weight and modified exhaust/emissions…..unfortunately.
 

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