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I have a 1998 Jeep Cherokee Sport, manual transmission (the 6 cylinder model, I believe 4.0L). It has 4 wheel drive.

I've lent the car to some friends recently who were 'rusty' with their manual transmission skills. Recently when I received the car back, I noticed that it is now difficult to put the car into gear while the engine is running, and the car is still. From what I've read this could be due to a clutch problem (namely, a broken pressure plate) or a clutch hydraulics problem (leaking/missing fluid). I checked the hydraulic system reservoir and its full.

The clutch 'feels' like it normally does, but here are the symptoms;

  1. You can easily put the car into any gear when the car is off.
  2. When the car is moving, its easy to change gears (though I haven't tried a rolling start/first gear test yet)
  3. When the car is on and not moving, If I depress the clutch and try to put it into ANY forward gear, it will not go into gear (although if I push it hard it will go in). That said, if I depress the clutch, and subsequently wait ~5 seconds, then I can easily put it into any gear.
  4. When the car is not moving, and I depress the clutch and rev the engine like crazy, the car does not pull (in other words, it does appear that the clutch fully disengages from the engine).

Since my hydraulic fluid levels are fine are these the symptoms of a bad clutch (e.g. broken pressure plate)? I would have guessed it was a syncro's problem given what I said in #3, but the symptom exist with all 5 gears. If the pressure plate is broken, why would it matter if the clutch is spinning or not (i.e. how does that affect whether I can put the car into gear or not when the clutch is fully depressed)? I would think if the pressure plate was broken it would just not go into gear even if the car was off, but maybe thats just my misunderstand of how clutches/manual transmission works.

Any ideas?

Zaid
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n00b
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4 Answers4

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There is one other thing that can cause what you are describing. There is either a pilot bearing or a pilot bushing that supports the input shaft of the transmission. I don't know which, but if it is a bushing, it would make sense based on your description.

If the borrowers slipped the clutch quite a bit and were in a position to use the clutch a lot, like in traffic or pulling a trailer, they could have overheated the clutch, which could have allowed the grease to melt and, left it a bit dry or cooked the grease enough to thicken it enough to cause the bushing to hold onto the input shaft, keeping it from stopping as quickly as it did before it was borrowed.

If it has a pilot bearing, a similar situation could have occurred. Overheating causing the grease to bind the bearing enough to keep it spinning longer than it did before. If either of these are the case, the transmission would need to be removed to replace the bearing/bushing.

One other thing. Having to wait long enough for the inertia of the spinning clutch to subside is quite normal. 3 to 5 seconds is not an unusual time to wait.

X-tech2
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Is it possible to bleed the clutch hydraulics? (I don't remember if the Jeep has that option off the top of my head.) If so, this is where I'd look first. If not, I believe you need to replace them. It seems as though the clutch is not quite letting go when you depress the pedal. The five seconds gives it enough time to spin down. The fact that you can drive the Jeep without issue tells me the clutch itself is in at least serviceable condition. Signs of clutch failure usually display themselves with the clutch slipping.

I wouldn't completely rule out the synchros, but I'd leave that for last. The reason I say this is because the 5-speed they put behind the 4.0l inline six in the Cherokee Sport should be the heavy duty one (as opposed to the weak one which they put behind the 4-cyl). I bought the 2 door version of the vehicle you are talking about for my son. The transmissions in them are pretty sturdy (but not indestructible as the engine seems to be ;-). If you can drive it down the road without issue, the clutch and transmission should be okay. The only thing to really look at after that are the hydraulics.

Pᴀᴜʟsᴛᴇʀ2
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I agree with the pilot bushing/bearing answer. It isn't seized or it wouldn't allow shifting after a few seconds. More likely it is dragging due to poor lubrication (thickened grease as above). As to the hydraulics... I can't recall if the slave cylinder is exposed on your vehicle (the majority are), but if so you can check. With the engine OFF, have someone depress the clutch while you crawl down there and observe for appropriate fork travel. Your scenario doesn't suggest the hydraulics, however, since they usually either don't allow release at all, or they release initially and then bleed down, allowing creep with the pedal depressed.

Mad Max
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I apologize in advance but this is going to be somewhat of an answer with a question to the original poster. (Hopefully he sees this!)

I have, to a T, the exact issues the original poster describes on a 2003 Wrangler TJ which clutch and transmission wise is very similar to a 1998 Cherokee. I had a brand new clutch, flywheel, throwout bearing, pressure plate, clutch arm spring and slave/master cylinder installed a few weeks ago. The issue was present before the replacement, seemed to go away for 2-3 weeks following the replacement but has since come back. The guy who did it said he re-used the old pilot bearing after greasing it(Why???).

So based on my experience my answer would be pilot bearing as well but I have yet to confirm it. I am hoping the OP might be able to confirm what happened with his Jeep.

Matt
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