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Please try this with your XJ and tell me results?

Quit pausing in N if you dont like it seems like yhe cure... I dont get it. Your test in N and N told you what? The u joint wasnt shot? Back lash is measured- not with a screw driver.
You cant video the "hammer on anvil" sound?

Yes mine is in the rear end.

Your theory is simply flawed. Pausing in N takes the load of the drive shaft. With out hearing it, sounds like a worry over nothing.

10 shops told you its all good?

You don't want to do whats asked to diag on the forums (this is through the web man) and check things that are possible reasons.

I feel bad this has consumed so much of your time... But your response to those helping seems to have you chasing your tail
 
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Just saw the video in 4 low. If the motor mounts are toast it will allow the drivetrain to lurch like that.. Also the low gearing is a big load... So pretty normal lurch.

Trany seems fine in those vids.. If mounts are good the carrier inside the diff would be where to look. Not convinced by the vid that it isnt normal
 
Checking backlash and possibly adding shims to the carrier ought to tighten it up so the lurch is felt more heard less
 
Well, including your test, I've now got one test in this thread indicating more clunk with a pause in Neutral and one test indicating just the opposite. To me this seems like such a simple request, but people here seem more interested in addressing other concerns than in just answering my simple question.
No one owes it to me to run this test...If a person doesn't wish to then that is their right. I disagree that the test serves no purpose and have explained in detail why. We will have to just agree to disagree. If anyone doesn't want to do the test then just move on to the next thread or explain to me the terrible harm that I am causing to the members of this forum by simply asking a question that would take seconds to answer, and there is no legal requirement for anyone to do even that. If I were personal messaging members nagging them about this then THAT would be wrong, but I'm not doing that.
Has it occurred to any of you that there might be even a slight possibility that you are wrong in your analysis of me and my XJ problem? You can believe that I am an idiot, stubborn, illogical, or whatever you wish, but I have heard that before from armchair experts who turned out to be dead wrong, so forgive me if I don't bow down and defer to your opinion just because you have more experience with XJ's than I do. Even "experts" can be wrong.
 
Checking backlash and possibly adding shims to the carrier ought to tighten it up so the lurch is felt more heard less

Thank you for running the test and reporting your results here...that makes you only one of two members willing to do that. I appreciate that.

I still maintain that the test results serve a valid purpose in determining what is normal for an AW4, and that determining that is the most logical next step for me. It sounds as if you disagree ( am I wrong?), but I do thank you for running the test, which is more than most here have been willing to do.
 
Your mannerisms are the issue not the jeep.. Scaring people off bro
I never said anything was pointless-mentioned the screwdriver video to see what you learned, what was the point? Didnt rule out much that has been posted to look in to.

Nothing is pointless if it helps you or anyone (should have clarified).

Your data is just flawed, bottom line. We are talking about a mighty bang from Thors hammer when stopping in N before going to drive right? Why then are you adding a 4LOW video to the mix? My jeep jumps like a sob when put in gear in 4 low. Is this what you dont like? Thats normal boss.

Of all the shops... Other forums.. There is one common denominator- you.

No one here has claimed to be an expert, no one has said anything with any certainty (since we arent in the jeep), or claimed that anyone else was wrong--- that is, EXCEPT YOU.

See the theme here? We came to help and you played "I know better then you" (without checking any of the KNOWN mechanical points that exaggerate the concern) and so, less people care anymore.

Get the damn diff and all mounts checked if you cant do it yourself. GL
 
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Your mannerisms are the issue not the jeep.. Scaring people off bro
I never said anything was pointless-mentioned the screwdriver video to see what you learned, what was the point? Didnt rule out much that has been posted to look in to.

Nothing is pointless if it helps you or anyone (should have clarified).

Your data is just flawed, bottom line. We are talking about a mighty bang from Thors hammer when stopping in N before going to drive right? Why then are you adding a 4LOW video to the mix? My jeep jumps like a sob when put in gear in 4 low. Is this what you dont like? Thats normal boss.

Of all the shops... Other forums.. There is one common denominator- you.

No one here has claimed to be an expert, no one has said anything with any certainty (since we arent in the jeep), or claimed that anyone else was wrong--- that is, EXCEPT YOU.

See the theme here? We came to help and you played "I know better then you" (without checking any of the KNOWN mechanical points that exaggerate the concern) and so, less people care anymore.

Get the damn diff and all mounts checked if you cant do it yourself. GL

I posted the screwdriver video in this thread for you solely because you had mentioned hands-only strength on the drive shaft. I wasn't suggesting that the screwdriver leverage would approximate the engine, just offering it because I already had the video and it only took about 5 seconds to add it to the post. If I include something, it MIGHT help someone. If I don't, it can't. So if I even suspect that it might help someone someday, I post it. No big effort required, so why not?

Same answer as above for the 4LO video...I had it, so why not include it along with the 2HI video? I figure that readers can ignore it if it is of no value to them. I made it partly because I was afraid that if I did NOT include it (in the original post) then someone would be asking "what happens if you engage the TC into 4WD...does it still do it? Easier for me to just include the video to begin with.

As far as the 2HI video, I can tell you that when I do not pause in Neutral that the difference seen at the differential is HUGE. When I do not pause in Neutral, it is more like a smooth *movement* of the pinion rather than a jolt, it rotates less, and does not have the rebound seen in the video.

You state that my data and my theory is simply flawed, and then state "Pausing in N takes the load off of the drive shaft". When in Reverse, the load on the driveshaft is a reverse load, agreed? So is it incorrect to assume that, if all other factors were equal, since the driveshaft has to rotate farther when going from Reverse to Drive than from Neutral to Drive, that more rotational momentum would be available when going from Reverse to Drive? So then, if all other factors were equal, then the "hammer would have a longer stroke" going directly from Reverse to Drive (without pausing in Neutral), causing more of a clunk/lurch that way than if you had paused in Neutral (reducing the hammer stroke) before going into Drive.
BUT, of course, all factors are not equal. IF the transmission impeller and input shaft (plus anything else attached to the input shaft when in Neutral) are able to free-wheel and spin up in rpm when the transmission is in Neutral, then you would have to add the rotational momentum of the transmission impeller and input shaft (plus anything else attached to the input shaft when in Neutral) to the calculation, and so this mean that really only real-world tests would indicate whether pausing in Neutral would increase or decrease the clunk/lurch.

I was told by one expert shop mechanic that the transmission impeller and input shaft (plus anything else attached to the input shaft when in Neutral) do NOT free-wheel and are NOT able to spin up in Neutral, but I was told just the opposite by a transmission shop mechanic. Searching online leads me to believe that the transmission guy was correct, but I still don't know the answer.

If the transmission impeller and input shaft (plus anything else attached to the input shaft when in Neutral) are able to free-wheel and spin up in rpm when the transmission is in Neutral, then that would be a possible explanation as to why pausing in Neutral causes my clunk/lurch, BUT....in order for that to be true, then ALL AW4 transmissions would also have smoother shifts into Drive without pausing in Neutral, with the only variance between AW4's being the DEGREE of difference between pausing and not pausing in Neutral. On a really tight XJ, the difference might be virtually un-noticable, whereas on a very loose XJ, the difference would be pronounced. The only way that I have to reasonably conclude that "all" AW4's behave this way is to ask fellow Jeep owners who have AW4's in their Jeeps...preferably XJ owners, to keep things less confusing.

So the above is my reasoning for wanting to know how others' AW4's behave. If someone feels that the logic above is flawed, feel free to tell me why.

I disagree with your assessment of what has transpired in this thread, but we are so far apart on that that we will just have to agree to disagree, I guess.

My intention in opening this thread was never to engage in arguments with readers or waste their time. My only goal was included in the Title: "Please try this with your XJ and tell me results?". How could I be more clear about what I was asking for? If someone chooses to engage with me in a conversation unrelated to that specific request and we disagree, don't get mad at me for wasting your time or not taking your advice. In a disagreement, BOTH parties believe that they are correct and the opposing viewpoint is incorrect (wrong)...what's wrong with that? If you want to believe that I am arrogant for believing that my test is valid and not accepting from other members that my test is a waste of time, then OK, I'm arrogant.
I think another factor at play here is that I don't want to spend $800 (quoted) to have my differential rebuilt if the transmission also needs rebuilding (~$2500), and vice-versa. I can't afford to, or don't want to, just throw money at this XJ until this mystery clunk/lurch disappears. I'd be better off selling it to someone who has the tools and garage space to do the work themselves, and just sell the XJ to them for $3000 under normal Blue Book value. That way they could also install a locker on the rear end and do other custom work while replacing/rebuilding the transmission and differential.
Again, thanks for your test results...I really do appreciate your doing that for me. :)
 
This is what you should do.

You’re in california. Post the car for $2500-3500 on CL. It doesnt even sound like that big of a problem. Dont even mention it. Most Xjs lurch. Sell the truck this summer when people are looking for camping beater vehicles. Im sure its a good truck. It runs, goes into 4lo, sell it for $2k maybe if you want it gone quick and forget about it.
 
I cant remember if you posted this on Jeep Forum or Cherokee Forum but i still think youre way overthinking/overblowing this "problem" ive had 4 xjs. 3 with the AW4. They all had a bit of a clunk or lurch when shifting gears.

These things were designed and built during a time when noise vibration and harshness levels werent at the forefront of design considerations. I guess you at least supposedly got a free transmission out of the deal.

Sent from my SM-G892A using Tapatalk
 
This is what you should do.

You’re in california. Post the car for $2500-3500 on CL. It doesnt even sound like that big of a problem. Dont even mention it. Most Xjs lurch. Sell the truck this summer when people are looking for camping beater vehicles. Im sure its a good truck. It runs, goes into 4lo, sell it for $2k maybe if you want it gone quick and forget about it.

Thanks, but no way I'm going to pass this problem on to some unsuspecting buyer.
 
I think the point was anyone looking for a 20 year old jeep will be ok with the "issue" you cant stand
 
I cant remember if you posted this on Jeep Forum or Cherokee Forum but i still think youre way overthinking/overblowing this "problem" ive had 4 xjs. 3 with the AW4. They all had a bit of a clunk or lurch when shifting gears.

These things were designed and built during a time when noise vibration and harshness levels werent at the forefront of design considerations. I guess you at least supposedly got a free transmission out of the deal.

Sent from my SM-G892A using Tapatalk

1.) I've easily driven over 100 different automatic transmission vehicles in my lifetime, being a vehicle operator in the Air Force, working as an Auto Driveaway driver, etc., including trucks, buses, and cars, and the only time that I ever experienced a clunk/lurch like this was when I accidentally revved up my 318 V8 with TorqueFlite AT to about 2K rpm and then put it into drive, which immediately disabled all forward gears.

2.) I'll stop worrying about it when someone can explain to me why it only clunk/lurches after a pause in Neutral.

3) What is so difficult about just trying my little 10 second test and telling me what happens?
 
I think the point was anyone looking for a 20 year old jeep will be ok with the "issue" you cant stand

If they are probably going to be OK with it, then why not disclose it to them?
See "Golden Rule". I'm from California but I guess I have Midwest values. At least what used to be Midwest values.
 
If they are probably going to be OK with it, then why not disclose it to them?
See "Golden Rule". I'm from California but I guess I have Midwest values. At least what used to be Midwest values.

I never said not to man
 
I thought I explained the why it does from N and not R... Load.

When in R it is under load and so the switch tp D keeps it under load. N takes the load off the trans and driveline. R to D keeps the rotaional masses under load, just changes the direction- so it only changes in the tranny aince you arent moving. When in N to D you are reapplying this force to the whole driveline.

Trans sounds fine- its new right??
If mounts are good there may be a backlash adjustment needed but sounds like probably not. With out pulling the axles and diff cover to check the carrier, bearings, and shims- you have to call it good.

800 is pricey for a stock axle... Maybe instead of a rebuild get a quote on new bearings- or axle seals and all that will be checked when in there
 
I thought I explained the why it does from N and not R... Load.

When in R it is under load and so the switch tp D keeps it under load. N takes the load off the trans and driveline. R to D keeps the rotaional masses under load, just changes the direction- so it only changes in the tranny aince you arent moving. When in N to D you are reapplying this force to the whole driveline.

Trans sounds fine- its new right??
If mounts are good there may be a backlash adjustment needed but sounds like probably not. With out pulling the axles and diff cover to check the carrier, bearings, and shims- you have to call it good.

800 is pricey for a stock axle... Maybe instead of a rebuild get a quote on new bearings- or axle seals and all that will be checked when in there

If you are saying that loose motor mounts could cause the clunk/lurch, I am liking that, because if they could, then, as you point out, this fits in nicely with the pausing in Neutral causing the clunk/lurch.

If so, I may need a physics lesson to fully understand how it works.

I've been sitting here trying to understand how this would work, and I THINK I have come up with an analogy that fits:

Picture a car where the huge, heavy engine block rotates around a stationary crankshaft bolted to the firewall, and the driveline is therefore driven by the rotating engine block instead of the crankshaft. If you revved that rotating engine block up to 1000 rpm and then popped the clutch, you couldn't possibly stall the engine, correct? The rear wheels would spin far before the engine block would stop rotating?
On the contrary, with a conventional setup, you only have to stop the relatively low mass of the internal moving engine parts to stall the engine?

Is the above why loose motor mounts would impart a heavier blow to the drivetrain than tight motor mounts?...because of the momentum of the heavy rotating engine block compared to the relatively low momentum of just the internal moving engine parts?
 
If you are saying that loose motor mounts could cause the clunk/lurch, I am liking that, because if they could, then, as you point out, this fits in nicely with the pausing in Neutral causing the clunk/lurch.

If so, I may need a physics lesson to fully understand how it works.

I've been sitting here trying to understand how this would work, and I THINK I have come up with an analogy that fits:

Picture a car where the huge, heavy engine block rotates around a stationary crankshaft bolted to the firewall, and the driveline is therefore driven by the rotating engine block instead of the crankshaft. If you revved that rotating engine block up to 1000 rpm and then popped the clutch, you couldn't possibly stall the engine, correct? The rear wheels would spin far before the engine block would stop rotating?
On the contrary, with a conventional setup, you only have to stop the relatively low mass of the internal moving engine parts to stall the engine?

Is the above why loose motor mounts would impart a heavier blow to the drivetrain than tight motor mounts?...because of the momentum of the heavy rotating engine block compared to the relatively low momentum of just the internal moving engine parts?

Damn...I just went out and watched the top of the valve cover while shifting (and this was with a cold engine so rpm's were like 950 instead of 730), and there isn't any noticeable movement at all, no matter what I do. If I add to that the fact that the shop I paid $90 to said that the motor mounts, transmission mounts, and rest of drivetrain were fine, I think that probably puts me back at square one, again.

Tomorrow I take it into the new transmission shop...if I learn anything new, I'll post it here. The motor mount theory made sense to me...I will ask the transmission shop about it, just in case. Thanks.
 
If there is a differential shop on the way to the transmission shop, stop there first.
 
If there is a differential shop on the way to the transmission shop, stop there first.

Tim, you've already stated that "the transmission behavior is within the range of "normal" for the 1980's Aisin Warner transmission technology", so, if you are correct, then my first stop should actually be at the psychiatrist's office, because I still maintain that this transmission behavior is definitely NOT within the range of "normal" for the 1980's Aisin Warner transmission technology.

What IS normal is how it shifts when I do not pause in Neutral.
 
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