meno19

Hi Guys this is my first post here. I recently just got a 2001 Jeep Cherokee Sport. I've got an issue that maybe you guys might be able to help me with.

The issue that I am having is that on a hard acceleration from a dead stop I get a vibration/noise that I can feel under my feet. I have had the car into a shop to get a look over and they said that yes the noise is there but the mechanic was unable to locate it at first. They said that the motor does not have any knocking or pinging. As well it was power braked and the 4x4 was all true and all of the joints look good. Now for granted this is great news but I still have the noise and would like to try to hunt it down. If i accelerate at a normal speed I don't normally get the vibration or it becomes much lighter. Once the car is moving I can hit the gas and I wont get the noise. Another thing i did was I also was revving the engine from the throttle body and if I gave it heavy throttle I could feel the vibration slightly through my hand. What I am worried about is if the vibration or noise is coming from the motor. Any ideas I'm glad to try anything to hunt down the gremlin.

Thanks for any advice in advance.

bsljacques

Same problem with mine! Still looking for answers!

meno19

Yeah how long have you had the noise for, and have you had a mechanic try to find it?

I think I posted on your thread too. I'm totally looking into trying to find it, it I do i'll let you know. I just hope its not the motor or tranny making the noise. But its only happens like yours from a dead stop and with a harder acceleration where you really torque the motor.

rich

Take a peek at your harmonic balancer or the crankshaft pully whatever you wish to call it.Just a thought.

TGL2000

it happens to me too in about 1st gear maybe, it seems like the whole car shakes but its not comin from the engine. It comes more from right beneath the floor...

bsljacques

I can't see how that would cause this problem...but I will check it out. The engine runs great and is strong and smooth. But I feel the problem is in the Transmission. I say that because it drives great other than getting on it at idle. I feel it by my seat and feet when I get on it and it's a growling noise that feels like a loss of power under hard acceleration. but once I get past that part I can accelerate hard and it's fine.

Very strange...but still leads me to think it's a transmission problem.

Steph74

I have the same thing happening (I have a manual with 200K miles). The sound is there only when accelerating, and in all gears. If I keep gas enough to maintain the speed, it goes away.

This started after I re-arranged my bastard pack to make it a little softer.
I have changed the motor mounts(that were shot) and it didn;t change anything.
All the U-joints look good for what I can judge.

I am planning to change the transmission mount but it does look good from what I see.

I have 2 theories that need checking:
1- When I rearranged the leaf spring pack, I put some of the leaves backward and changed the angle of the axle. I also lost about 1/2" in the rear.
I will start with this.....
2-I have a leak of ATF (meaning TC for me). It drips on the front driveshaft double U-joint. So I think the seal there is bad, and I noticed that when I turn the front driveshaft there is a slight poping noise that seem to come from there....

So this look a little more scary and I will check that too....

One thing is sure is that the noise started after I redid the pack and the leak was already there... so I don;t know if I am on the right track there....

I am sure going to follow these 2 thread about the noise

TrekkerJmm

For you guys with automatic trans you can check the flywheel out for cracks in the flex plate where it bolts to the Torque Converter, its a common problem with jeeps.
Take the inspection cover off near the bottom of the trans and look up there with a light, there should be 6 bolts holding the flex plate to the TC...Tj

bsljacques

Yep....I did that already.....all good and no cracks. This was my first check after reading that they can be loose and cracked flex plates.

McRay

Mine vibrates and makes a noise at times and its the baffles in the muffler to tight to replace - make noise at different speeds.

meno19

Thanks guys for all of the replies. Tonight the car is going over to my mechanic. Going to have a second opinion done on the car. Plus to top it off last night when driving home from work while stopped at a light the oil pressure dropped to around 12 psi and the check gagues came on. When put into neutral or driving the oil pressure returns to normal PSI. Want to have that looked at, the vibration looked at and have the guy check to make sure I dont have the cracked head issue these Jeeps can get. Plus I have an engine light on for P0441. The car has been difficult since I got it just hoping it doesnt turn out to be a lemon was going to be my daily driver. I will let you guys know what I find out.

mdcmn7

Do you have any lift on the truck?? Those drive line angles can shake the crap out of it

mdcmn7

Your cherokee isnt being difficult, it is being a jeep

meno19

Yeah no lift the truck is stock. What angle is the rear drive shaft supposed to be in relation to the transfer case?

Yeah thats something I will have to get used to, see my other car is a 2003 Honda Civic Si. Much different ride.

ntomsheck

My vote is for exhaust.

Two weeks ago, my exhaust needed to be repaired, so I cut it off, and welded a new section in it. I went a little too quick and noticed it was slightly off-kilter. From this point forward, I would get this vibration under my feet during any kind of reasonable acceleration (40%+ throttle)

Yesterday, I cut the exhaust again, lined everything up perfectly, and welded it again. I also stuck a jack under the I pipe and bent it upwards to get me a little more clearance between the pipe and the trans-cross member. Viola, no more vibrations (or banging sound when I go over a hard set of train tracks).