Hello everyone!

I need your help because neither my mechanic and I have found out what's wrong with my H3, 121K mi, 06 ADV, right now located in Monterrey, México.

I took my H3 to the shop to have the Diff and Sway bar bushings replaced. The Diff bushing was rebuilt (and is pretty solid now) because they could not find the part and dealer sells the whole crossmember. Meanwhile they were working on it, they did a general check of the entire drivetrain and found out my front driveshaft was bad. They took it off and rebuilt the CV on the shaft.

The day I picked it up and drove it I noticed a vibration with a kinda humming sound, this was NOT present before the repairs. Immediately I took it back to the shop. After two hours they call me to test the H3 with the mechanic; the vibration was gone, but when I got back he told me he took off the front shaft (We were in 4HILock). 2 days later they call me. They told me the shaft was bent, so they did a replacement of the shaft (just the bar, the u joint and CV are the same). Shaft was balanced and tested at the shop.

After all this was done the vibration is still there. I got angry with the mechanic because he told me he does not know what is going on and is not being held responsible.

I climbed down to check things out: Theres no play at all in the shafts and CVs seem ok, same with other components.

After driving a while I noticed this: Vibration and sound is present at any speed; at low speeds you feel like a continuous knock, and a high speeds it vibrates and it seems to become stronger when turning. If I let go the gas the vibration is still there but you can barely notice it. You can definitively hear it although you notice it if you turn off everything inside as it is not loud.

I'm planning a road trip this weekend and I'm worried about having a larger problem in the middle of the roadtrip. I really need advice because although I consider I know a lot about cars and stuff, I still cannot find out what's wrong.

Thanks in advance!

 

Start with the easy stuff, put in a new Moog UJoint for the front of the front drive shaft.

Does not make sense to "rebuild" a worn U Joint. Replacements are readily available, cheap, and you can upgrade to a Moog with a grease zerk if you want.

If a U Joint is worn, they begin to make noise, first a hum, then whine, chirp, and clunks. If worn too much, they can vibrate.

The rear CV joint of the front drive shaft cannot be rebuilt, but it can be replaced. Did they replace the rear CV joint? They vibrate a ton when worn out.

 

I didn’t stay at a holiday inn last night but my money is on prop shaft cv.

 

Sorry Doc, when I said rebuild I meant I didn't buy a new whole driveshaft, but replaced the specific components (CV and U joint) and I meant the CV, not the joint, my bad, but both were replaced apparently. I initially thought about wrong parts but the shaft is rigid with no play at all in neither CV or U joint. Mechanic says there's nothing wrong with them.

I am located in México and I won't be going back to US until New Year, I can have parts shipped at my home until then, but I need a quick fix for it meanwhile. Anyway, thanks for the suggestion, i'll get the Moog parts.

What I don't understand is why the vibration becomes stronger when turning. Can it be something in the side diff bushings or CVs?

 

Sounds like a half shaft going bad or the pinion bearing if you have already addressed the prop shaft.

 

I will check it out. Thanks for your help!