Diff or Wheel bearing noise?

[89Vette]

Just my 2 cents, but I feel like in general that the VX has a certain roughness to it. I remember when I first got mine (25,000 miles) that I for the longest time was thinking there was a bearing or a gears, etc that may be worn because of a whine or rub sound i was hearing when letting off or under certain rolling conditions.

With it not getting any worse and having grown used to it, it now seems normal, but when I drive my wife's pilot or another, more "civilized" vehicle it becomes evident when I go back to the VX that it's a bit more beastly than other cars.

It's also a bit rougher and louder in the higher RPMs than other SUVs, etc.

So, I don't want to lull you into buying something that may have issues, but the fact you have heard the same thing in three different VXs has me thinking you are experiencing the same thing I did.

Even my best friends JGC seems quiet in comparison.

Throw some dynamat in it and call it a ride!!!

Good luck.

Ask yourself if people would have paid $30k for the level of roughness/vibration you're talking about. Ask yourself again if the problem might have occurred on yours before the 25k mileage point? Certain vehicles do have "characteristics". But engineering, parts, part failures, and other aspects play a part in the final result.

Generation 1 JGCherokee's definitely have a problem with their differential bearings. They are louder and fail in a high percentage of cases. If the result is normally vibration/loudness vs breaking down, people could come to the conclusion it's just a characteristic of the vehicle. To me, it was a problem.

Again, I'm imagining what a new specimen would have felt like. Whether this is primarily the intake manifold problem, wheel bearing vibration, differential vibration, or other drivetrain bearings, it's something that could be found and improved. Or,,,you could say "Eh...whatever."

FWIW,,,the Isuzu tech did say manifold gaskets were problematic on the 3.5L motor. Whether it's true and/or he was blowing smoke, I don't know. Guess I could do a search or post a thread on that topic.

Considering how much more forgiving injection might make manifold leaks, maybe it is an issue (with the VX)? The tech called the gaskets "cheap plastic". Maybe FelPro or some other manufacturer makes a better set. Regardless, I'm trying to decide/learn how likely a manifold leak could feel like a vibration vs a miss. Maybe at just the right amount of cylinder imbalance -- just short of a lean miss??? I did also note an idle very close to an outright miss when it gets hot. I suspect this is a real issue. (Maybe it explains why the mpg is so bad (worse) for some owners?)

BTW: Compared to other 4x4 setups/brands I've driven, this Isuzu design does seem to have it's share of gear whine/drag. When you let off the gas, you can feel the drivetrain dragging the vehicle slower than other 4x4 system (i.e., Quad-Trac II or AWD car). It has more of the character of a truck,,,big truck,,,maybe even a BEAST. Probably part of the reason for the "Little Beast" nickname. Had I not noticed the pronounced vibration in park revving the motor, I might have come to the same conclusion.

I also found a thread on fan bearings causing this problem. So there are multiple possibilities. There are also multiple perceptions that could be formed from verbal description vs actual 1st-hand experience of individual symptoms.