1999 Chevrolet Express 3500
Quigley Conversion

Currently it is running 285/75-16 but I'd like to go to an 18" rim and want to know what's the largest diameter I can get away with without doing any mods to the suspension.

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1999 Chevy Quigley 4x4.

These are 285s which are close to 31". I wonder if I can do 35"? I think I can do 33" no problem.

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1999 Chevy Quigley 4x4.

Just keep in mind the larger the rims, the shorter your sidewall, which sometimes equates to a harsher ride due to less rubber. Plus you may not be able to air down the 18" tires as much for off road use. I'm sure there's some that are running 18's, but most of the older conversions were 16" before they switched to 17's to clear the larger brakes. I'm running 315/75/16 but I had to sneak the front axle forward for tire clearance on the fender. You could check with Don at boulderoffroad.com as they do a lot of Chevy 4X4 conversions swapping in solid axels, and is familiar with what will fit under them even with quigley's set up.

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'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
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