Diagnose rattle under shift knob?

truckeejeeper

truckeejeeper

NAXJA Forum User
NAXJA Member
Location
Northern California
So - I just had my shop (been using them for 20 yrs.) put in a new clutch (LUK) on my 1991 4.0 4x4 5 speed about a month ago. Everything new under there, master, slave, flywheel, bearing etc. Recently thought, I've started to hear a squeaking/rattling that sound like its right under the shift knob/shifter unit. The sound comes when I push in the clutch pedal/disengage clutch (like at a stoplight.) If I shift it into neutral and let up the pedal, sound goes away. Push in pedal and shift into gear, sound comes back. I can't tell if the sound is there while driving (no carpet kit, its pretty loud) but I assume it is. Sound is like a chirping/squeaking, little bit a rattle. Like something isn't lubed or tight or both. What is this noise? It's new for sure. Was there before new clutch, or right after clutch install. May be getting louder.

Thanks for any ideas

- TJ
 
That sounds like a defective clutch release
bearing. Since it's new, maybe it was shipped
dry (no grease) from factory...???
 
Or maybe just Chinese crap!!!
 
If it happens while the clutch pedal is released and the vehicle is in gear but not when the pedal is released in neutral, that's pretty odd. Forgive me for asking, but are you sure that the clutch is properly adjusted so that its not slipping? Assuming the clutch is properly adjusted to prevent slippage, the my next thought is that the clutch disk, which is likely spring damped, is squeaking as the springs are flexed.
 
maxbraketorque said:
If it happens while the clutch pedal is released and the vehicle is in gear but not when the pedal is released in neutral, that's pretty odd. Forgive me for asking, but are you sure that the clutch is properly adjusted so that its not slipping? Assuming the clutch is properly adjusted to prevent slippage, the my next thought is that the clutch disk, which is likely spring damped, is squeaking as the springs are flexed.
Click to expand...

I agree. That is an odd situation. Doesn't sound to me like the throwout bearing. Typical symptoms for the throwout (or release) bearing are that it makes noise when the clutch is depressed, but not when the clutch is released. There should be no relative movement of the throwout bearing when there is no pressure applied to the clutch. Both sides of the bearing should be turning with the clutch and the input shaft.

Although I suppose there is a caveat to that: Do you have a hydraulic throwout bearing? Or, IOW, an internal slave cylinder for your hydraulic clutch? That might make a difference, although given the issue changes when the transmission is in neutral I am still not sure how it would be the throwout bearing (hydraulic or not).

I would be most inclined to think something is going on inside the transmission, perhaps something involving a shift fork.

Can you affect the noise by wigging the shifter around? Perhaps applying light pressure in one direction or another? If yes, it might be the case that you simply need to rebuild your shifter. There is a big nylon (or some type of plastic...UHMW maybe) cup/washer at the base of the shifter. Or at least there is supposed to be. Mine was gone. I didn't have odd noises, but I can imagine how the lack of that piece could affect how the shifter sits relative to the internal shift linkage and potentially cause a situation such as you describe. I imagine the shop may have removed your shifter to remove the transmission and then reinstalled it without replacing a worn cup/washer. That part may have been slightly moved out of position and finally gave up the ghost.

Search ebay for "Jeep AX15 Shifter Kit" and you should find something like this:https://www.ebay.com/itm/-Jeep-AX15-5-Speed-Transmission-Shifter-Repair-Kit-AX15-SK/271777038002?epid=23017023686&hash=item3f472c7eb2:g:aEAAAOSwBp9aUTue&amdata=enc:AQAHAAAA8HSYLnmo05YttKTrCEo9TZINsH6tjYJePLUkem9rbmPiYCOV9DmiV3/pOy3iiPFrBU1xE7pYJhQe0LT+CQXINxdNoaQ/2ZvQpDog9AH9TTPFuWTfmH7Tar7SJGsl35RtqNQ0qTcTfLruuIGpMyJSRBOALvTKvNgHiP6yKJt6E5agVatuFsE1g8kjG50dag5k/LqK+uMV4AJlwTK3MieBlngmmeqz1Zk7HxV9aTWeZKRJrJE/4eWD21X3D5b6YgEtfi7KWfmYDJfup3zQ1zaDL2J7jvezvHMytZyUhci1wCcNRrnsJurwzqGmMf+jl0PJiQ==%7Ctkp:Bk9SR_zBoPXwYA&pageci=c72bd9c2-0e8a-468a-be8a-ad861ae93c50&redirect=mobile

That big blue washer is the piece which you may be lacking in your shifter.

That is my half-educated guess.
 
Hi - ok great info. I do have the internal slave. So to be clear, if the clutch pedal is pushed IN, it makes the sound. It's a squeaking/chirping, vey slight rattling, rotational sound. It is constant. Like something is spinning but isn't greased and/or tight. This is when the truck is moving or stopped. Like, I hear it every time I come to stop and put in clutch. It doesn' matter what gear I shift it into, neutral, whatever, if the pedal is in, it's making that sound. If I put it in neutral and let UP the pedal, the sound goes away. I can really hear it when I'm pulling out from a stop (clutch 1/2 in, etc.) I can't tell if it's happening when I'm driving because it's so loud lol. But it's a new sound, from after I got the clutch package put in. Now I have the habit of putting it in neutral at every stop so I can let up the pedal and not have to hear it. But if it's some bad, it's only going to get worse I'm sure. So hm

I'll investigate the shifter washer thing. but it sounds deeper.
 
Okay. That sounds like a throwout bearing.

Take it back to the shop and show them. Did they provide the parts? If yes, I would hope they would not hesitate to warranty the work. This is why they put their mark-up on the parts they provide.

BTW, you are supposed to put it in neutral when you come to a stop. The throwout bearing is only supposed to handle intermittent duty. Intermittent meaning a matter of very few seconds at a time.
 
HI - Yes they did supply the parts. Good to know about the throwout. I do put it in neutral at red lights...but not stop signs. Fwiw, I'm the original owner of this rustbucket. This is it's 3rd clutch and I've never heard this sound before in 30+ years. So something is off with the install. I'll def be taking it back to them.
 
UPDATE: Ok, took it back to shop where I had clutch installed. They agreed and replaced the throwout bearing. Just went to pick it, drove off and... noise STILL there. Exactly the same. not a whiff of change. I don't think they *didn't* do the work, that would be too shady. But it def was not the problem I guess. Arg.

I can deal with my rustbucket looking ugly. But I HATE when it is not running smoothly. I would post a video of noise if I could figure out how. Rattle/squeak and it's driving me nuts. Any other ideas out there...?

Thx!
 
Well, if they did indeed replace the
throwout bearing, two other things come
to mind. As you mention the pilot bearing
is suspect, although they're usually replaced
with a clutch job. Another thing would be a
disc spring making noise, possibly because
the disc was installed backward...?(Don't even
know if that's possible with an XJ clutch???)
 
Hmm.. this is a pretty good shop. Although its full of BMWs and Audis now... boo. I'm gonna try to post the rattle when I get a sec. Its def rotational. Is the throwout bearing spinning when the clutch pedal is pushed in? The clutch plate stops spinning, correct? I guess it could be rubbing on the flywheel still. Hell, maybe they did install it wrong. I'll try to get audio/video up.
 
The throw-out bearing will spin anytime it's in contact with the pressure plate regardless of whether the clutch actually dis-engages, that's why "riding the clutch" causes premature TO bearing wear.
 
Gotcha. Well the clutch disengages ok. But man is there a rattle/squeak with the clutch in. No matter the gear. When I rev it, the noise picks up speed. So I'm assuming it must be the TB. But supposedly the shop just put in a new one, to replace the old NEW one. So.. is it just a trash component always? It's a LUK clutch. If it's not the bearing, maybe something is out of alignment...? Everytime I shift, I want to reach under the shifter a smear some grease on something, bc it's so annoying...
 
Well you need to have a long talk with the shop! You would think that the second time would be enough and would also replace the pilot bearing while they are in there lust to rule it out!
 
RCP Phx said:
Well you need to have a long talk with the shop! You would think that the second time would be enough and would also replace the pilot bearing while they are in there lust to rule it out!
Click to expand...

+1

Something isn't right, and the shop should have already tried to make it right.

The shop should also be capable of diagnosing the problem, and should have been trying to do so while they had things apart. They should have been able to hand you the old "new" throwout bearing and show you what was wrong with it. And if they themselves could not find something wrong with that bearing they should have spent some time trying to figure out if something else was going on. They also should have test driven the vehicle, and accordingly should have found that things were still not fixed, at which point they should have been curious and should have pursued further diagnosis. The fact they did not do these things calls their intelligence and character into question.

Whether or not you let them continue to work on your vehicle is a decision you will have to make, but a discussion with them is certainly in order. It could just be that they assigned your job to a tech who can't find anything with two hands and a map. That happens. Or it could be worse, and the entire operation is a cluster.

This is the challenge with paying for services. The longer I live the more I find that too many of those who provide services are working beyond their level of competence.
 
Following up: Anak - I agree with you 1000%. I think the art of diagnosing a problem is being lost, in most shops around where I live. Usually they just plug new cars in and look for the reader. I've taken my Jeep to 10 diff shops around here, and got it back with the same problem not solved, usually just with a new part thrown on. I've gotten a lot of, "I don't knows." Idk it was easy, I'd have figured it out myself. That's why I brought it in to a "pro." It's usually not a good sign when I drop it off and the guy pulling it into the garage grinds the hell out of my gears just putting in over the lift. I could rant on, but going in to a shop is about my least favorite thing to do. But I don't have a garage and mine is my DD, so I need to have big things done.

In any case, to this shop credit (where I have been going on and off for 20+ years,) the owner jumped in jeep with me right away after I brought it by for a listen. He couldn't hear what I was hearing, but he put his clutch guy in it with me and we drove around the block. He DEFINITELY heard it. So he said they had replaced the throwout bearing unit, which is a sealed unit, so he is eliminating that. He said it may be the transmission? I'm not sure how that could be. But the owner was like "leave it here right now, we need to make this right." I couldn't do that, so I'm bringing it back next week. They 100% seem committed to solving it, free, but I will want more details as they go through it.

I'll keep everyone posted. Really curious what this spinning/grinding/rattling could be. (With clutch pedal IN, regardless of gear. Pedal OUT, in neutral, is dead quiet smooth spinning sound.)

Stay tuned -
 
When the clutch is pushed in, the transmission doesn't even turn a bearing or a shaft so that eliminates the transmission from any possibility! You are not getting any good mechanics there!
 
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