HelloAs you can tell from the photo, my build is a head scratcher to most so allow me to explain myself. First and foremost I can’t leave anything alone. Most everything I’ve ever driven has seen mods, some good some bad. Like my attempts at land speed racing on antique Harley Davidsons, I find myself drawn to improbable builds.
I bought this 99 GMC Safari AWD when my sons joined scouting and it became apparent so did I. Tried and True drivetrain with the torquey 4.3 Vortec engine, the venerable 4l60e automatic, the 7.625” rear end out of the camaro/firebird platform, the 7.25” IFS front diff from the S-10 4x4’s and the rest of the front end from the K1500 4x4. GM had the start of something fun, I just had to push a little bit.
First to go was the np136 one speed transfer case. It’s electronicly controlled to transfer torque to the front when wheel slip is detected. Upon further review, the np236 case from the S-10 was the same case with low range stuffed inside. I went so far as to buy two broken tc’s a136 and a 236 and built a case with parts from both to ensure that when I stated they were interchangeable I wasn’t talking figuratively but stating fact. With the addition of a dash switch and a dozen or so wires added to the existing harness I had 2hi 4hi 4lo and 4auto which is the same setting as my original AWD and it was a direct swap.
Next was to address the open/open diff situation. I needed something that would get power to both sides but not cause me hate and discontent on the street. I settled on a Torsen unit I found on eBay. It came out of a firebird and was a direct swap.
While researching the np236 swap I found the Zr2USA forum. They were instrumental in locating the tccm and wiring harness I needed. I quickly came to realize that these guys were seriously twisted and laser focused on offroad improvements on their rigs.
With so much being shared between our platforms I was quickly finding other items to swap into my van
One such item was a cast iron front differential found only in S-10 4x4’s with manual transmissions and the mp233 transfer case. I found one such unit from a properly equipped Zr2 to ensure it had the 3.73 gears found in all Zr2’s to match my vans 3.73’s. It was into this cast iron diff I had installed the at that time never before seen 7.2” Torsen carrier for a first of its kind cast iron limited slip. I swapped this unit in place of the stock aluminum open diff and upgraded both sideswith Detroit axles.
The S-10 pickup and my van shared the same length rear spring though the S10 was +5” in arc. I swapped in a set of S10 rear springs, lifted the front with a 3” body lift and a mild torsion bar crank. I increased tire size by 2” for a total of 6” of lift.
So I now have a van with twin torsens like an Audi Quattro, a two speed tc and underside armor from a Zr2 and a lift that puts the floor of my rig at mid thigh height. It handles like a dream and corners like a sports car. It has plowed thu three feet of snow yet I’d let my mom drive it. It really is a fun rig. I look forward to getting it well offroad to see just what it’s capable of-for I truly have no idea
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