Groaning noise upon acceleration

[iroc86]

My Cherokee just started making an unusual groaning noise whenever I accelerate moderately hard. It sounds like it's coming from the front passenger side, as if from the spring or suspension. I've checked underneath for rattling parts and I also loosened up the tension on the rear shackle bolts to see if that had anything to do with it. Unfortunately, nothing changed. It also makes the noise in 4WD, though not quite as much.

I first noticed the sound just after replacing the rear output seal on the transmission (in other words, I had to pull the transfer case, remove the driveshafts, and drop the exhaust). Everything went back as it came off and I'm positive there's nothing loose.

These Jeeps typically make all sorts of odd noises under acceleration, but this one just doesn't sound normal. I'm leaving on a trip tomorrow morning and would like to get it resolved before I depart. Any ideas?

 

[87manche]

u-joint or wheel bearing comes ot mind. have you jacked up the front wheel and spun it to see if you can feel/hear anything odd?

 

[Digger87xj]

check your engine mounts... they go bad frequently.

replace them with OEM from jeep... 2 year unlimited mileage warranty

 

[iroc86]

I replaced the front wheel bearings and U-joints about 3000 miles ago, but I'll check it anyway. I'm gonna try removing the front driveshaft to see if that changes anything (the only component with non-new U-joints).

EDIT: Didn't see your post until after I did mine, Digger. I'll check those, too. Might have put a bit of stress on them due to pulling the t-case (and letting the driveline sag a bit lower than usual).

 

[Matthew Currie]

My 95 made a noise on acceleration that turned out to be a misaligned fan shroud. When the engine flexed under hard acceleration the fan hit it.

 

[iroc86]

You know, this noise does sound like the fan hitting something (first thing I thought of). Unfortunately, mine doesn't do that .

I checked out a few more things and still can't figure out what's making the noise. Oddly enough, it went away during my troubleshooting. I wonder if it'll crop up on the trip. It's probably nothing to even worry about, but it still makes me a bit nervous. Thanks for the quick help, guys.

 

[TF8]

If you wheel it and have punched the cat or muffler up into the body it will rattle. I just put down my rear seat when I realized the passengers seat was slanted at about a 20 degree angle to the passengers side. So much that it was touching the pillar. I pulled out the seat to see the floor punched up in the shape of the cat. Now that I have pounded the floor back down to level out the seat the cat rubs the floor making the sound you are describing.

Tyler

 

[xjtrailrider]

Check and make sure the exhaust is not rubbing the crossmember that runs under the t-case. The exhaust sometimes will drop aqnd rub the upper side of the crossmember.

 

[iroc86]

I got back from my vacation and thankfully didn't have any issues with the 800-mile round trip. I've never had it out that far and it ran like a champ .

The noise came back sporadically, however. Thanks for the tips on the exhaust; I'm going to reseat the pipe at the manifold and see if that helps at all. I know nothing is rubbing on the crossmember because I already resolved that issue when I got the Jeep back on the road last year (a new tranny mount added a few inches more clearance).

Even so, the noise really sounds like it's coming from the engine, an accessory or something. I picked up a new power steering pump because this one's been moaning pretty badly for a while... maybe I'll get lucky. I was also wondering about the idler pulley. Those things were always failing on my YJ and made a somewhat similar noise.