When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
i was about to ask why you want big tires until i seen your location.i guess you probably dont have snow issues.lol those big wide tires dont do good on the ice and stuff i prefer the cookie cutter tires for my purposes.
not sure about an 88, or how much its different from my 92 f350 with the danna 60 but I have 305-70 r16s and they only rub on the bumper slightly if i hit a hard angle with the wheel turned
i cleared 37's with a 4" spring and 1 1/2" body lift. it cleared with just the spring, but made inner fender well contact under flex. only added the body lift for the turbo but it worked great for the tires too. superlift claims 38x12.50 tires for their 4" lift, and 40x12.50 for their 6" lift. i dont recall what the offset has to be though.
If you put the 37's on some OEM wheels they would fit better. You may still have some frame contact but it would be minimalized by the OEM offset. Aftermarket wheels have more offset and cause issues sooner as you increase tire size. I've seen a guy running 37" XZL's on steelies with minimal rubbing on an 86 F-250.
fwiw, our local BF Goodrich dealer told my brother that anything larger then 265R7516 will need "a lift", due to "small variations" in suspension systems & body configuration. - Richard's rig is "dead stock" with FOMOCO steel wheels/hubcapas & in good condition, both & body & suspension.
i looked his truck over, about 10 days ago, when the front end was re-ligned & i believe the tire guy is CORRECT.