I'm sorry if this has already been covered, I looked and didn't find anything. I am looking at a 90 club cab 4x4 gasser to replace my rot box 91.5 reg. cab. I think this swap should be straight forward. I have only a couple questions. Will my tranny cross member just bolt up underneath? I should just have to lengthen my rear driveshaft right? Second, will my front leaf springs bolt into the shackles on this truck. Obviously, I plan on swapping both axles too. Will my intercooler fit in this truck without too much trouble? While the engine is out would be an excellent time to do a converter. What is the absolute best for high horsepower towing? Will my 91-93 front clip bolt on this 90? Will I have to swap my fuel tank too? Is there anything else I'm forgetting. Thanks for the help.

 

Been here done this on a non compurterized gasser. Crossmember is a bolt in. Leaf springs are a bolt in. Need to swap the I/C core support into the gasser, also a bolt in. Front clip is also a bolt in. Drain fuel tank and pour in some good stuff (diesel), fuel line runs along the drivers side frame rail where as the gasser runs along the pass side, easy fix. Not sure about the gasser computer being compatable, but at least it should have an external voltage regulator. Good luck, you wont be disappointed.

 

Thanks very much for the help. The advice is encouraging. I think I will definiteley go ahead with this.

 

I was in the planning stages of doing the same thing with a 87 W150. Donor was a 91 W250 N/I. Wound up selling the 87 to my uncle and buying a 96 for my brother. Still have the donor, just waiting for a good recipient, has to be a crew cab though.
I know the frame sizes where the same from my 91 to the 87, it was recommended that I box the front section of the frame to prevent cracking around the shock mounts. Your 91.5 might have the larger frame, but that won't make a difference.
You might wind up making a whole new drive shaft, Club cab trucks have 2 piece drive shafts with a carrier bearing. I don't know if a 1 piece one would be too long or not, drive shaft shop or someone here might know better.
As far as a converter goes, try the big shops like Goerends, DTT, ATS, Suncoast, etc... Hughes always comes to mind also. I'm running a Goerend converter in my 93 and love it.

 

If the front clip on your '91.5 isn't too bad you should swap it onto the '90. At least swap the core support over.