blistovmhz
NAXJA Forum User
- Location
- Vancouver, BC
Reposted from http://www.bcjeepclub.ca/index.php?topic=25528.0
I've probably posted about this 10x in various forums and never found the answer. Figure I'll try one last time before biting the proverbial bullet and just replacing everything from the clutch to the wheels (and hopefully solving the problem).
Three issues.
1. Driveline slack - Heaps of slack in all gears. Hit gas, wait a bit, BANG and we're moving. Let off the gas, wait a bit, BANG and we're slowing down. I don't have another Jeep for reference so I don't know which parts should have what tolerance. There's a very small amount of play in the rear output of my NP231, and about 8 degrees of play in the front output. If I disconnect the driveshafts and crank the diff inputs manually, there's a bit of play on the rear and more on the front. Seems like everywhere I look, there's a little bit of play. Knowing what's normal for each part would help a lot I suppose, but haven't been able to find any specs posted anywhere. I'm dreading the inevitable "everything is worn everywhere, buy a new Jeep" response.
I thought it was worth noting that the play in the rear tcase output vs. the rear diff input is about equal, just like the play in the front tcase output is about equal to that of the front diff input. By design, the NP231 looks like it's supposed to have a lot more play in the front than rear. Not sure if the front gears should as well.
2. Axle knock - When turning hard one direction, then the other, my rear right axle sounds like it's slamming against the c-clip or bearing, depending on which direction I'm turning.. This wouldn't worry me too much if I didn't drive it like a rally car, but as it is, I tend to drift my XJ more often than I should, and I suspect that lateral play will eventually result in the c-clip breaking and losing an axle/wheel, mid drift. Anyone know how much lateral play is normal? I recall having the same knock in my 90xj (without issue), but none in my 92 or 96.
3. Clutch disengagement - Clutch doesn't always fully disengage. Pedal feels normal, doesn't feel like air, bled about 10x with no change. Clutch works perfect for a while, then intermittently wont' fully disengage. Sometimes pull up to a light, hold clutch in first, everything's good for a few seconds, then the clutch will start screeching and pulling, then it'll shuttup and all's well again. Checked everything I can without access to a dry space to work. Master and slaves both seem okay, no leaks, no lateral play at the pedal/firewall as far as I can tell.
So this brings me to the following:
I need more braking power regardless, so I was going to swap on some rear discs to my 8.25. As it is though, the 8.25 may or may not be in good condition (the gears are only 3 years old, but the previous owner who installed them was handicapped and didn't tighten any of the suspension components, so I suspect he may not have shimmed and set pinion angles properly either). I figure I can spend $300 on the disc conversion, but then the axle may need more work anyhow. maybe makes more sense to just swap out with a D44 or 8.8 that's already got discs.
As for the clutch, I suspect broken or weak pressure plate fingers, or ... possible a really weird problem with the TOB? The fact that the problem comes and goes is throwing me off. If it were consistent, I'd immediately suspect the pressure plate fingers or air in the line.
Do problems 1 and 3 come together in some unholy union? Could the clutch disc springs be worn/broken/missing, causing both my disengagement problems as well as the jerky driveline? I've never looked at the clutch disc on the XJ. I assume that if it's a two disc clutch, and the springs are missing entirely, I'd expect both DS slack as well as mysterious clutch issues...
I've probably posted about this 10x in various forums and never found the answer. Figure I'll try one last time before biting the proverbial bullet and just replacing everything from the clutch to the wheels (and hopefully solving the problem).
Three issues.
1. Driveline slack - Heaps of slack in all gears. Hit gas, wait a bit, BANG and we're moving. Let off the gas, wait a bit, BANG and we're slowing down. I don't have another Jeep for reference so I don't know which parts should have what tolerance. There's a very small amount of play in the rear output of my NP231, and about 8 degrees of play in the front output. If I disconnect the driveshafts and crank the diff inputs manually, there's a bit of play on the rear and more on the front. Seems like everywhere I look, there's a little bit of play. Knowing what's normal for each part would help a lot I suppose, but haven't been able to find any specs posted anywhere. I'm dreading the inevitable "everything is worn everywhere, buy a new Jeep" response.
I thought it was worth noting that the play in the rear tcase output vs. the rear diff input is about equal, just like the play in the front tcase output is about equal to that of the front diff input. By design, the NP231 looks like it's supposed to have a lot more play in the front than rear. Not sure if the front gears should as well.
2. Axle knock - When turning hard one direction, then the other, my rear right axle sounds like it's slamming against the c-clip or bearing, depending on which direction I'm turning.. This wouldn't worry me too much if I didn't drive it like a rally car, but as it is, I tend to drift my XJ more often than I should, and I suspect that lateral play will eventually result in the c-clip breaking and losing an axle/wheel, mid drift. Anyone know how much lateral play is normal? I recall having the same knock in my 90xj (without issue), but none in my 92 or 96.
3. Clutch disengagement - Clutch doesn't always fully disengage. Pedal feels normal, doesn't feel like air, bled about 10x with no change. Clutch works perfect for a while, then intermittently wont' fully disengage. Sometimes pull up to a light, hold clutch in first, everything's good for a few seconds, then the clutch will start screeching and pulling, then it'll shuttup and all's well again. Checked everything I can without access to a dry space to work. Master and slaves both seem okay, no leaks, no lateral play at the pedal/firewall as far as I can tell.
So this brings me to the following:
I need more braking power regardless, so I was going to swap on some rear discs to my 8.25. As it is though, the 8.25 may or may not be in good condition (the gears are only 3 years old, but the previous owner who installed them was handicapped and didn't tighten any of the suspension components, so I suspect he may not have shimmed and set pinion angles properly either). I figure I can spend $300 on the disc conversion, but then the axle may need more work anyhow. maybe makes more sense to just swap out with a D44 or 8.8 that's already got discs.
As for the clutch, I suspect broken or weak pressure plate fingers, or ... possible a really weird problem with the TOB? The fact that the problem comes and goes is throwing me off. If it were consistent, I'd immediately suspect the pressure plate fingers or air in the line.
Do problems 1 and 3 come together in some unholy union? Could the clutch disc springs be worn/broken/missing, causing both my disengagement problems as well as the jerky driveline? I've never looked at the clutch disc on the XJ. I assume that if it's a two disc clutch, and the springs are missing entirely, I'd expect both DS slack as well as mysterious clutch issues...
, but definitely not the muffler. I can grab the wheel when it's lifted, and give it a good shake in and out of the axle tube and there's some noticeable movement.
