Knocking sound when brakes are on
#16
While you have it on the lift, pull the inspection cover off of the trans and check the flexplate for cracks. Mine stated as a very slight tick and soon became a very loud knock. It would be more noticable sitting still either in park or in gear. When under acceleration the broken pieces would lock together and the noise would stop until I let off the accelerator.
#17
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Year: 1988
Model: Cherokee
Engine: 4.0L
While you have it on the lift, pull the inspection cover off of the trans and check the flexplate for cracks. Mine stated as a very slight tick and soon became a very loud knock. It would be more noticable sitting still either in park or in gear. When under acceleration the broken pieces would lock together and the noise would stop until I let off the accelerator.
I'm grateful for everyone's input especially as I know I'm going to have a few issues with this car (it's got such high km's, 393k, didn't cost much to buy and doesn't have any major body issues) & will be asking for help & information quite a bit.
#18
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Year: 1993
Model: Cherokee
Engine: 4.0 H.O
Check your trasmission mount. Mine had gotten all worn out and was sagging causing the exhaust to hit the crossmember causing a bad knock especially when stopped and in gear. its a 40 dollar or so fix.
#19
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easiest way to check control arm bushings is while in reverse, tap the brakes enough to get it to knock, and have a buddy look to see if they are visually moving in their mounts.
i also agree that it could be your transmission mount.
but it could also be your brake caliper bolts loose or missing. i've had that happen to myself and seen it twice on other xj's.
i also agree that it could be your transmission mount.
but it could also be your brake caliper bolts loose or missing. i've had that happen to myself and seen it twice on other xj's.
#20
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Year: 2000
Model: Cherokee
Engine: 4.0L I6
Sounds like something different, but mine has a rattle when engaged in drive and stopped at a light, etc. Someone told me to check the catalytic converter shield, or possible motor mount gone bad?? When I shift into Neutral at the stop, or start driving, the rattle goes away.....for what it's worth--I haven't figured it out yet.
#21
Sounds like something different, but mine has a rattle when engaged in drive and stopped at a light, etc. Someone told me to check the catalytic converter shield, or possible motor mount gone bad?? When I shift into Neutral at the stop, or start driving, the rattle goes away.....for what it's worth--I haven't figured it out yet.
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#24
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Year: 1988
Model: Cherokee
Engine: 4.0L
easiest way to check control arm bushings is while in reverse, tap the brakes enough to get it to knock, and have a buddy look to see if they are visually moving in their mounts.
i also agree that it could be your transmission mount.
but it could also be your brake caliper bolts loose or missing. i've had that happen to myself and seen it twice on other xj's.
i also agree that it could be your transmission mount.
but it could also be your brake caliper bolts loose or missing. i've had that happen to myself and seen it twice on other xj's.
#26
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Year: 1988
Model: Cherokee
Engine: 4.0L
I had a look at the driveshaft u-joints...they seem ok. Of course trying to get the vehicle to replicate the problem in front of my buddy (who is a licensed mechanic) proved impossible (typical, I guess...bets on it doing it again tomorrow??? lol).
The only thing that was different was that it had been in f/t 4wd on the drive over (it snowed here today so was a little slippery out) & we had just changed the CPS.
The only thing that was different was that it had been in f/t 4wd on the drive over (it snowed here today so was a little slippery out) & we had just changed the CPS.
#27
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Year: 2000
Model: Cherokee
Engine: 4.0L I6
#28
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Year: 1988
Model: Cherokee
Engine: 4.0L
I had a look at the driveshaft u-joints...they seem ok. Of course trying to get the vehicle to replicate the problem in front of my buddy (who is a licensed mechanic) proved impossible (typical, I guess...bets on it doing it again tomorrow??? lol).
The only thing that was different was that it had been in f/t 4wd on the drive over (it snowed here today so was a little slippery out) & we had just changed the CPS.
The only thing that was different was that it had been in f/t 4wd on the drive over (it snowed here today so was a little slippery out) & we had just changed the CPS.
#29
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Year: 1989
Model: Cherokee
Engine: 4.0L I6
i have the same noise while accelerating on my 89 i think it has to be a bushing or a u joint somewhere, never even thought of the trans mount i will check mine tomorrow lol
#30
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Year: 2000
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After some playing around, my rattle is, in fact, coming from the transfer shift lever. When it "rattles" at a stop, etc., all I have to do is pull it up slightly, and it's good for a while.
What is involved in fixing this permanently (besides holding the lever up constantly! LOL)
Thanks!
What is involved in fixing this permanently (besides holding the lever up constantly! LOL)
Thanks!