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1989 Isuzu Trooper

Vehicle Stats:

Vehicle: 89 Isuzu “Super” Trooper
Engine EFI 4 cylinder
Transmission: Auto with overdrive
T-case: Stock
Axle –Rear: Rear from '86 Toyota, Detroit, 5.29
Axle - Front: 84 Toyota front, 5.29, alloy shafts, birfield eliminator
Tires: 35” Wild Country on 15 x 8 rims
Suspension - Front: Front, 6 leaf Rubicon Express, 2.5” spring over springs
Suspension - Rear: Stock rear springs with spring over and 2” blocks
Other: Custom rock sliders, double arm crossover steering


The Beginning:

When Laz pulled up to the shop in his “Super Trooper,” I almost died laughing.  I don’t have a natural foods store next door, and I don’t sell tobacco water pipes. Who really drives a trooper?

To my surprise, the man walked in my door! He started rambling off some story about taking his trooper to the highlakes, and his buddy jumping up and down on the front bumper to get traction.

I wasn’t really interested in the escapades of Laz and his stoner, hippy friends. I started daydreaming about topless college girls on beer-can beach...


The Project:   (Click the icon for photos)

The day the trooper showed up, I wanted to hide it until I was ready to do the work.  This was a top-secret project and we didn't want the information leaking into the wrong hands so we rushed it over to our secret storage facility... well.. actually, I was a little embarrassed to be working on it. (no offense Laz).

The first thing I did was build the axles. In the front, I used an 84 Toyota straight axle.  The first thing I did was strip it and check it out. The knuckles had just been rebuilt, and everything else looked great.

I replaced the stock 4.10’s with 5.29 Yukon gears, and a Yukon install kit.  From there, I found my dumpster once again with the stock Birfield joints. I replaced the axles with a Yukon Birfield eliminator kit.  This kit comes with 4340 chromoly dana 44 shafts and spicer 760x u-joints.

It also comes with new spindles to accept the larger stub shafts. At the same time, I installed 4x4 Labs double crossover steering arms.  With these arms, I would not need to move the steering box forward.

It puts the draglink in front of the axle, and the teirod in the rear of the axle. We used Chevy tierod ends and 1.25 x .219 DOM tubing for the tierod and draglink.

For the rear, I chose to use an IFS Toyota rear. We also put Yukon 5.29 gears in it, with a Detroit locker.  The factory drum brakes were kept, and the Isuzu e-brake lines were adapted to hook up.

Due to the fact that it came from an IFS Toyota, we put 1.5” wheel spacers on the front to make the width match.

On the first day, we decided to start on the rear.  We removed the Isuzu disc brake 44. (It is a weird hybrid cross, and I decided not to screw around with it.) We cut the perches off the Toyota rear, and sprung it over with the factory Isuzu springs. We used 2.5” blocks to achieve our optimal height.

We also threw away the factory 2 piece driveline, and cut the cross-member out. We replaced the old cross-member with a custom bent tube one. With, the rear done, we threw two junk tires on it to turn it around. Damn it looked cool!

It was now time for the fun part. Out came the BFH and the plasma cutter!  We showed no mercy!   The sledge hammer was swinging and the sparks were flying. It took hours to cut out that stupid IFS.

It even took longer to grind the frame clean.  In the end, we decided to plate the outside of the fame with 3/16 steel.

For the front shackles, we sleeved the frame and bushed it to accept Confer shackles.  For the springs, we used 2.5” Rubicon Express, 6 leaf, reverse eye springs. They gave us the exact height we were looking for to clear 35” tires.

Once the stock Isuzu pitman arm was reamed out to fit the double pivot Chevy draglink end, we pulled it out front to flex it out.  Boy were we surprised!

I have never seen a trooper look so tough!  We made sure everything cleared and measured for shock dimensions and bump-stop locations.

We pulled it back in the shop, bent up the front shock hoops, and started messing with the driveline. I took of the rear driveline flange, and machined it and redrilled it to accept a Toyota CV. We had E & J Engineering in Auburn, Ca. make the Toyota CV rear driveline.

In the front, I did the same thing with the output flange on the transfer case. I machined the flange to accept the Toyota pilot, and drilled it to accept the big pattern Toyota flange.

The big pattern Toyota flange is capable of almost 45 degrees. I also re-drilled the front flange to the same big Toyota bolt pattern. E & J Engineering in Auburn built the front driveline as well. We used the high angle Toyota flanges on both ends, and an 8” Toyota slip in the Center. By putting the slip at the top, there was no trimming required on the crossmember.

The last part of the project was to make the rock sliders. Beau bent up some 1 3/4" x .120 wall DOM tubing. He mounted the sliders to the frame in 3 spots, and capped the ends.

Despite the fact that the Trooper is a gutless wonder, it drives like a dream! With the Rancho 9000 adjustable shocks, the ride can be tightened up for curvy roads, or loosed up for off-road.

Who knows, you may run into this “Super” trooper on Rubicon some day.