Spare Size / 1989 Pickup Wheel Compatibility with 3rd gen

1.) Planning to get new wheels and tires for my 2019 TRD Off Road 4x4. Wheels will be Icon Rebounds (Part # 1817858347SB) that are 17x8.5's with 4.75" BS and 0mm Offset. The tires I want mounted are Cooper S/T Maxx sized 255/80r17. In the event of having a blowout, can y'all please advise me as to if I may run into any possible issues if I utilize the stock steel rim from my spare and replace the existing spare tire with a Cooper S/T Maxx in 255/85r16? I want my spare to be sized the same as my four primary tires, but have no interest in upgrading the spare wheel. Also, would this larger spare tire fit under my truck with no modifications, or will I need to cut or relocate anything?

2.) I still have the 15" wheels from my old 1989 Toyota 4x4 Pickup to which I had previously mounted four brand-new and very aggressive mudders (Grip-Spurs) from the Arkansas Farmers Coop sized 7.00-15LT. If I were to swap out my primaries with this set for a weekend of nasty off road mudding, would there be any rubbing or fitment issues mounting these smaller 15" wheels?

Thanks for your help!! This forum is an awesome resource and I really appreciate the opportunity to learn from everyone's shared experiences.

 

1. You can put the 255/85/16 on the spare and put it under the bed. Only light modification to make it fit, pounding the ears flat under there. And some relocate the hangaer too. https://www.tacomaworld.com/threads...to-new-adventures.528480/page-5#post-17311994

2. No. You cannot put 15” wheels on the 3rd gen.

 

Just to build on #2, its due to the larger brake calipers. This same reason is why 4runners can't run 16's, and Tundras can't run 17's.

 

Thanks, fellas!! Exactly what I needed to know. Much appreciated.

 

Will the 15's fit on 1st or 2nd gens?