mikeny59 said:
Do harmonic balancers on 4.0's fail catastrophically or just start wobbling and are detected visually.
Are they servicable or an oem part?
Mike
Mike,
The harmonic balancer on my stock '92 XJ 4.0 was wobbling and my
front main seal was leaking oil badly.
My mechanic noticed this, and that the serpentine belt was worn (and might be the original belt!) and recommended replacing all the parts at the same time. I agreed.
He explained that if you don't replace the harmonic balancer, it can fail and take the belt out with it, possibly damaging the engine in a way that might require a rebuild.
I figured that a few hundred dollars repair was better than a few thousand.
I had him do all of the work, and it cost $300 including parts and labor.
The belt cost $75. I don't remember what the HB cost, but it was about the same as the belt or maybe less.
I don't think he had to get OEM parts for anything, as he would have informed me of the delay while parts were obtained.
Here where I live in the Rocky Mountains, Jeeps are common.
My mechanic keeps certain Jeep parts in stock because they require replacing often, so I can't say for certain that it wasn't OEM, but I don't think it was.
My advice is the same as my mechanic's advice: replace it before it fails, or risk damage to your engine and a towing charge.
It's also nice to have piece of mind.
Hope this helps.