1990 suburban diesel swap and 4wd conversion

Maybe I should have said which frames would be the easiest to use and which would be more difficult

We usually don't delve into swaps on the site due to their complexity and all of the unknowns involved. So if you don't get any replies that is why.

Just buy a 4x4 Suburban. The amount of work and expense is not worth it.

I know that already but this was my good friend's truck who was killed in November. So I'm going to do what I would like to do to this truck. The work will give me something to do.

The Suburban frame and the Chevy truck frames were different in that. The Suburban Frame Had much straighter side rails. Where the Chevy pickups had a substantial rise in the rear for the bed. Body mounts would be different also. Good news though, The 2500 Suburban 4 wheel drive trucks used A solid front live axle and leaf springs. You can easily convert your 2wd frame to 4wd if you can weld, or have friends that do. All of the parts needed for the swap can be purchased from a salvage yard. As for the Diesel. You can drop in the 1990 6.2/6.5 diesel will fit fairly easily as this was available from the factory. The later turbo diesel 6.2/6.5 is the same long block but will be harder to package due to the addition of the turbo hardware. The Duramax can work but will require major surgery and a body lift of at least two inches to get it to fit. as well as custom springs to carry the weight. Hope that's helpful

Thank you very much Steve. Very helpful info. I have another question for you. I have been seeing a lot of guys with Chevy trucks use a cummins diesel. From what I understand it is a good and fairly easy fit. Is this true?

Finding a donor 4x4 Suburban should not be that hard. You could swap bodies since you are attached to the one you have. In my area old Suburbans are plentiful and cheap. Look around and you might even find a diesel.

Good Point on the Cummins swap. The 6bt 12 valvers were non electronically controlled. These were the 1989 to 1998 models. They are a great swap. But they are heavy Nothing less than a Dana 60/70 series front axle should ever go under them. But they are easy to find. And Gm used them so it's an easy upgrade. But the BT6's are expensive due to demand. The ISB Series used from 89 to 07 had minimal electronics. Common rail fuel and electronic pump timing advance. Both these engines have massive aftermarket support but the early isb's were not as reliable as the BT6's. The 6.7 Liter ISB that came out in 07 and is still in use is all electronic And a much tougher swap. There is aftermarket support for this series but the parts are VERY expensive. Pair up a BT6 with a TH400 transmission, There are adapter kits and you have a monster on your hands.

On a side note. The Cummins is a popular swap Partially due to the fact that its non electronic. But it makes more power than the 6.2/6.5 Detroit Diesel sourced GM engine. And Much easier to package than a Duramax or Powerstroke. And who puts a ford engine in a Chevy anyway?