Project Isuzu Vehicross: Part 6 – Getting Sprung With Old Man Emu

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In theory, once the retaining clips are removed, a few taps of the hammer will release the U-joint from its flange.  Reality is never that simple.  Heat cycling, corrosion, and road grime will eventually fuse the bearing cap in place (and these joints had seen 170,000 miles and over 14 years of use).  After half an hour of hammering, punches, and swearing, we gave up and grabbed the angle grinder.  Through the magic of timers, we were able to get a reasonable shot of badass spark making.
By cutting two legs, we will only have to break loose one cap at a time instead of two.  This makes the job a hundred times easier by not only cutting in half the number of rusty caps you’re trying to push out, but also removing the side loading caused by any misalignment between the two bearings.  With the joints cut, we pressed out the bearing caps with a gear puller.
Maximum suckage.
The new U-joint is a direct replacement to its predecessor.  However, the joint’s new needle bearings should solve our grinding noise.  Both old U-joints were very notchy when we wiggled them by hand.  Our new U-joints are made by PDQ.  They include a new grease fitting (which we installed after pressing in the new joint) and new C-clips.
Before assembling the new U-joint, we lightly sanded the bearing caps of the driveshaft to remove the corrosion that caused us so much trouble.  A light greasing also makes pressing in the new joints much easier as well as help slow corrosion between the U-joint flange and bearing cap.  Be very careful when assembling the new joint.  Losing any needle bearings means buying another U-joint.
While we had the driveshaft apart, we also checked the slip yoke to ensure it was in good shape.  It was, so we cleaned off as much old grease as we could and repacked the slip joint with fresh goo.  We were planning to replace the grease seal, but could not find one.  It seemed to be in good shape, so we’re not losing sleep over reusing this one.  
Replacing the U-joints was a pain in the ass, but necessary on our newly lifted VX.  With the new U-joints, our driveline noise has…not been eliminated at all.  That’s right, after two different weekends busting knuckles and grinding U-joints, our driveshaft still groans.  

After fixing the obvious problem, we took a second look and realized the lift has greatly reduced the pinion angle of the driveshaft.  Combine that with an increased angle on the transfer case U-joint (from the lift) and you would get harmonics and driveline noise.  It is possible we may be able to adjust the pinion angle with stock suspension links, but we may have to invest in a set of I4X adjustable links to get the angle we need (or find a local fab shop to do the job for us.  Sadly, despite my work in SAE, I don't currently own the tools needed to make these relatively simple parts).  A rebalance of the driveshaft may also be needed since it took so much fighting to get apart.  Finally, if all else fails, we can look at high angle u-joints and possibly having a double cardan joint fitted.  For most off-roaders, spacing the transfer case with a new cross member would do the job, but with the VX's IFS, this would cause trouble with the front driveshaft, which uses a CV joint (and since the dfiff is bolted to the subframe, we don't have any angle problems here).

On the one hand the added lift has definitely helped our ride quality problems.  On the other, it has added a few others.  The VX has reasonably good front suspension design, so it's possible some TLC on the steering will rememdy a lot, if not all, of our steering issues.  The driveshaft problems will take more work to solve.  This is not the first Isuzu to be lifted, nor will it be the last.  Once we have a permanent solution, we will definitely share it here.  Would we recommend this lift kit?  Obviously with the driveline and steering problems we are experiencing now, no.  But if we can fix these issues, we may change our minds.  For now, we'll have to buckle down and put on our problem solving hats to get the VX in fighting form again.

1 comment

  1. I have really appreciated your Vehicross tutorials. I went with your advice on the Curt install and it made the project a breeze. I have a 1999 that I would like to tackle the lift on but with all the concerns you shed light on I am on hold for now. Looking forward to more of your posts.
    Thank You

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