NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > OEM Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #31  
Old November 9th, 2018, 14:23
Afireinside Afireinside is offline
NAXJA Forum User
 
Join Date: Jan 2017
Location: Denver co
Posts: 105
Re: Clunk/lurch into Drive, but not Reverse

There are too many weird things going on here. I'm no master mechanic but I'm smart enough to know a clunk pretty much will never come out of an automatic transmission directly. I most certainly would not rebuild one,especially if I was a transmission expert. There are several things that could cause a clunk,most common is bad u-joints(most people grab the driveshaft,while the vehicle is on a slight incline,in park with tension on the drive train) and say feels tight,same with the rear gears or possibly even the t-case. I like to put them on fairly level ground, a tire chock both for and aft of a wheel of your choice. Put the transmission in neutral and grab the rear driveshaft and twist back and forth.
You should find it fairly quick.
Good luck
Reply With Quote
  #32  
Old November 9th, 2018, 14:33
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

With transmission and transfer case both in neutral, I'm measuring 4.5 degrees of play on the rear drive shaft (2.5 mm or .1").

(2.5mm play / 200mm circumstance) x 360 degrees = 4.5 degrees of play.

I've had a friend switch between reverse and drive while I was under the rear end, and the only thing for certain is that it never clunks/lurches going into reverse and always clunks/lurches going into drive. It's AS IF the idle was at about 1500 RPM and then of course there would be a clunk/lurch, but the idle is only 740 RPM which seems to be normal for an XJ...AND, it NEVER does it in Reverse.

I'm going out right now to video the differential area so I can post exactly how violently it clunks/lurches when put into Drive.
Reply With Quote
  #33  
Old November 9th, 2018, 19:17
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

Here are two videos of my differential while being shifted mostly back and forth from Reverse to Drive with an ~4 second pause in Neutral each time. First video is with TC in 2H, second video is with TC in 4L:

https://www.youtube.com/watch?v=yLV5XDG1J90&t=28s

https://www.youtube.com/watch?v=99t7lKHlUqw
Reply With Quote
  #34  
Old November 9th, 2018, 21:54
RCP Phx RCP Phx is offline
NAXJA Forum User
 
Join Date: Mar 2003
Location: Phoenix,Az
Posts: 12,721
Re: Clunk/lurch into Drive, but not Reverse

That's a lot of play in the ring/pinion.
Reply With Quote
  #35  
Old November 9th, 2018, 21:57
CJ'sXJ CJ'sXJ is offline
NAXJA Forum User
 
Join Date: Mar 2016
Location: Pahrump
Posts: 13
Re: Clunk/lurch into Drive, but not Reverse

After watching your vids, defiantly in the diff. I know you did a static test to get your 4.5* but to me it looked like a little more than that. Combo of r & p plus side gears worn? You might have play in the thru shaft too. Found it interesting that it would back off a little bit when put into N and I don't think you can generate that much force by "hand" that you would be able to go up against it as it were and have it spring back a degree or two. Pull the cover and have a look, curious to know what you find!
Reply With Quote
  #36  
Old November 10th, 2018, 05:18
Tim_MN's Avatar
Tim_MN Tim_MN is offline
Freakish Hand Strength
 
Join Date: Mar 2003
Location: Minneapolis, MN
Posts: 6,731
Re: Clunk/lurch into Drive, but not Reverse

Have a knowledgeable technician inspect the differential and spider gears, check the ring and pinion gear pattern, check the carrier bearings, and measure the pinion preload and backlash.
__________________
.
.

Quote:
Originally Posted by bimmerjeeper

Go ahead and slam the liftgate down on a blanket, and see how long you are laughing.
Quote:
Originally Posted by soyjer

Tim MAY be 100% correct, but why would a person automatically pick him as the expert .....
Reply With Quote
  #37  
Old November 10th, 2018, 06:58
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

The 4.5 degrees (0.1") was by hand using a lever as hard as I could, with trans & tc both in Neutral. I can only guess that although the diff obviously has enormous play, that enormous play only occurs when an enormous (engine driven) jolt is applied.
I'll post a video of a hand/lever test today, so readers can see the huge contrast.

Quote:
Originally Posted by CJ'sXJ View Post
After watching your vids, defiantly in the diff. I know you did a static test to get your 4.5* but to me it looked like a little more than that. Combo of r & p plus side gears worn? You might have play in the thru shaft too. Found it interesting that it would back off a little bit when put into N and I don't think you can generate that much force by "hand" that you would be able to go up against it as it were and have it spring back a degree or two. Pull the cover and have a look, curious to know what you find!
Reply With Quote
  #38  
Old November 10th, 2018, 11:20
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

Quote:
Originally Posted by CJ'sXJ View Post
After watching your vids, defiantly in the diff. I know you did a static test to get your 4.5* but to me it looked like a little more than that. Combo of r & p plus side gears worn? You might have play in the thru shaft too. Found it interesting that it would back off a little bit when put into N and I don't think you can generate that much force by "hand" that you would be able to go up against it as it were and have it spring back a degree or two. Pull the cover and have a look, curious to know what you find!
Reply With Quote
  #39  
Old November 10th, 2018, 11:22
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

'99 Jeep Cherokee XJ differential play (TC & Trans in Neutral). Much less visible play when doing manually - when not using engine power and sudden transmission engagement into Drive to jerk the drive shaft around:

https://www.youtube.com/watch?v=WRZI...ature=youtu.be
Reply With Quote
  #40  
Old November 10th, 2018, 11:31
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

Quote:
Originally Posted by Rob Mayercik View Post
98K doesn't seem like much - I'm still on the original 27-spline version of that with my '92 and it's got 256K miles on it with no issues.

Could whatever holds the pinion into the diff housing be loose (crush sleeve? yoke nut?), causing something that normally shouldn't rotate to have to spin a little before you start taking up the R&P mesh slack?

In other words, is the amount the rear driveshaft twists when you put it into Drive and it clunks equal to or greater than the amount you can twist it by hand? If putting it into drive gets more rotation, perhaps there really is something "else" rotating under the greater torque of the engine/trans that shouldn't be?
At this point, my amateur guess would be that something is seriously loose in the differential, but, as you say, such that it is only really noticeable under engine force.

Videos:

'99 Jeep Cherokee XJ differential play (TC & Trans in Neutral). Much less visible play when doing manually - when not using engine power and sudden transmission engagement into Drive to jerk the drive shaft around:

https://www.youtube.com/watch?v=WRZI...ature=youtu.be

https://www.youtube.com/watch?v=yLV5XDG1J90&t=36s

https://www.youtube.com/watch?v=99t7lKHlUqw
Reply With Quote
  #41  
Old November 10th, 2018, 19:47
Runnin'OnEmpty's Avatar
Runnin'OnEmpty Runnin'OnEmpty is offline
NAXJA Forum User
 
Join Date: Apr 2003
Location: Southeast USA
Posts: 1,079
Re: Clunk/lurch into Drive, but not Reverse

I once had an old car develop a huge differential play like yours, happening over a period of time. It turned out to be loose ring gear bolts. The cure was simple, I just installed lock washers under the bolts, and never had any more problems. I've never heard of this happening before or since, but it's worth a check...
Reply With Quote
  #42  
Old January 23rd, 2019, 17:31
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

Quote:
Originally Posted by soyjer View Post
FOLLOW UP: Just got my XJ back from the transmission shop. It was in there for over 2 months, during which he completely rebuilt the transmission and the torque converter, replaced the valve body and the transmission control module and even the transmission case, and at the end he said that he and all of his fellow transmission shop owners on a network were all completely stumped as to why none of that fixed the problem. He did not charge me for any of this, because he said that he does not charge if he can't fix the problem. He was still pretty much 100% sure that the transmission would be the problem, but at that point he said the only thing that I could do would be to actually replace the entire transmission with a rebuilt one, and hope that doing that would solve the problem.

So... It seems that one of these things has to be true:

1.) All of these Transmission Specialists plus a certified Jeep Master Mechanic are all completely wrong, and the problem is not related to the transmission at all, and my transmission mechanic invested over 2 months of time plus the parts and labor required to rebuild the transmission and torque converter etc. based upon a wrong assumption that the transmission was the problem.

OR

2.) Somehow my transmission has such a rare and freakish problem that it was able to avoid being fixed despite the transmission almost being completely replaced.

I'll just have to keep searching the internet to try to find someone else who has experienced this obviously very rare problem.
Took the XJ to a good general mechanic (2nd time...but different shop/mechanic this time) and he checked all of the mounts and play, etc., and he also thinks it is the transmission.
I bought a OTC 5610 TRANSMISSION/ENGINE OIL PRESSURE KIT, and checked the line pressure, and it meets spec. in Neutral and Drive (61-70 psi), so it shouldn't be a line pressure problem.
Reply With Quote
  #43  
Old May 26th, 2019, 02:54
dsbhealer dsbhealer is offline
NAXJA Forum User
 
Join Date: Aug 2015
Location: Denver
Posts: 2
Re: Clunk/lurch into Drive, but not Reverse

The play in your rear axle, as shown in the video, is a major cause for concern. When you step on the brake and shift from neutral into gear, the power from the engine/ flexplate/ torque converter/ transmission/ rear driveshaft must go through the rear differential before it hits the rear brakes. Play anywhere along that path can cause problems. I had a problem with my 2000 xj where the bolts that hold the flexplate to the torque converter were loose and the holes wallowed out on the flexplate, causing part of my lurch from neutral to drive or neutral to reverse.



You can try an experiment to see if it is indeed the rear axle (from your video, it really looks like the rear axle to me). Block the wheels to prevent the jeep from rolling. remove the rear driveshaft from the rear axle pinion and then remove the driveshaft from the jeep by sliding it off the slip yoke. Put the transfer case in 4wd part time hi. With your foot on the brake, try shifting and see if there is less lurch and clunk with the front axle compared to what you were previously experiencing with the rear.


Changing out a rear axle is not that hard of a job, easier than a rebuild. Chrysler 8.25 axles are readily available on craigslist or the junkyard. You might even be able to find one with a decent locker installed. Just be sure to get the correct gear ratio if doing a swap.
Reply With Quote
  #44  
Old May 26th, 2019, 06:15
Tim_MN's Avatar
Tim_MN Tim_MN is offline
Freakish Hand Strength
 
Join Date: Mar 2003
Location: Minneapolis, MN
Posts: 6,731
Re: Clunk/lurch into Drive, but not Reverse

With no measurement data about the gear set-up and shims, no metal sparkles in the gear oil, and no leaks from the seals, why would someone change the rear axle ? Agreed it is a simple job and a low cost part, but shot gunning random parts ( or transmission rebuilds ) at any type of undiagnosed problem or vague symptoms is not an efficient or effective repair strategy.

Loose flexplate bolts would have no logical effect upon the rear differential, which by the way, seems to be the most logical root cause of the symptoms.
__________________
.
.

Quote:
Originally Posted by bimmerjeeper

Go ahead and slam the liftgate down on a blanket, and see how long you are laughing.
Quote:
Originally Posted by soyjer

Tim MAY be 100% correct, but why would a person automatically pick him as the expert .....

Last edited by Tim_MN; August 18th, 2019 at 06:21.
Reply With Quote
  #45  
Old May 26th, 2019, 15:02
soyjer soyjer is offline
NAXJA Forum User
 
Join Date: Aug 2017
Location: California
Posts: 145
Re: Clunk/lurch into Drive, but not Reverse

Quote:
Originally Posted by dsbhealer View Post
The play in your rear axle, as shown in the video, is a major cause for concern. When you step on the brake and shift from neutral into gear, the power from the engine/ flexplate/ torque converter/ transmission/ rear driveshaft must go through the rear differential before it hits the rear brakes. Play anywhere along that path can cause problems. I had a problem with my 2000 xj where the bolts that hold the flexplate to the torque converter were loose and the holes wallowed out on the flexplate, causing part of my lurch from neutral to drive or neutral to reverse.

You can try an experiment to see if it is indeed the rear axle (from your video, it really looks like the rear axle to me). Block the wheels to prevent the jeep from rolling. remove the rear driveshaft from the rear axle pinion and then remove the driveshaft from the jeep by sliding it off the slip yoke. Put the transfer case in 4wd part time hi. With your foot on the brake, try shifting and see if there is less lurch and clunk with the front axle compared to what you were previously experiencing with the rear.

Changing out a rear axle is not that hard of a job, easier than a rebuild. Chrysler 8.25 axles are readily available on craigslist or the junkyard. You might even be able to find one with a decent locker installed. Just be sure to get the correct gear ratio if doing a swap.
The experiment you suggest is one that my landlord would probably allow me to do here (especially if she doesn't know), so I'll try that...thanks.
Did your clunk/lurch also happen when you did NOT pause in Neutral?
On mine, shifting from Reverse to Drive without pausing in Neutral results in NO clunk/lurch.

The "bolts that hold the flexplate to the torque converter were loose and the holes wallowed out on the flexplate" fits my above symptoms, I think, because the transmission input shaft only ever spins in ONE direction, so only shifting from Neutral would ever allow that input play to be noticeable. Shifting quickly from Reverse to Drive retains pressure on the input such that loose bolt and bolt hole play would not be noticeable...or at least that seems logical to me.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Lurch in drive ABNCherokee OEM Tech Discussion 0 October 18th, 2014 19:49
clunk when i reverse and turn bryceyoda Modified Tech Discussion 4 October 1st, 2008 21:35
Lurch when putting into drive? darjevon OEM Tech Discussion 3 May 11th, 2007 09:17
Front End clunk in Reverse jeepsrock OEM Tech Discussion 9 December 7th, 2006 19:52
Clunk-Reverse/Braking Bowzer OEM Tech Discussion 5 December 1st, 2005 18:04


All times are GMT -7. The time now is 05:19.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014