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Unread 05-06-2013, 05:01 PM   #31
97hero
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1997 XJ Cherokee 
 
Join Date: Apr 2013
Location: Phoenix, AZ
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the mech fan does'nt hit, if I open the hood and stand next to it while someone gives it gas pulling forward I can see the motor move forward just enough to rub the elec fan...I will get some pics when I get home from work and post em up...its real close maybe 3/4 of an inch. and it seemed to get worse after replacing all the mounts.

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Unread 05-06-2013, 05:16 PM   #32
97hero
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Here are a couple pics...
2013-05-06_16_08_03.jpg   2013-05-06_16_08_14.jpg   2013-05-06_16_07_51.jpg  
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Unread 05-06-2013, 05:36 PM   #33
79chiefs
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Whoa, that is close. How did the area around the mounts look, has the motor ever been replaced, and accidents?
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Unread 05-06-2013, 05:44 PM   #34
97hero
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Looked pretty normal around the mounts...Not sure if the motor has been replaced, just bought this about a month ago and dont have much details from PO, I know that when I was replacing the mounts they were not very tight at all as a matter of fact the motor mounts were about finger tight. I cant see any front end damage but the airbag was deployed sometime prior to me buying it.
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Unread 05-06-2013, 05:50 PM   #35
79chiefs
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I would pull the electric fan temporarily, so you can drive it. What ever happened to it is causing this.
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Unread 05-07-2013, 05:18 AM   #36
Kevin108
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I had the same problem after removing a t-case drop. The years of sitting at an angle had stretched the mounts out and when I accelerated, the fan clutch was rubbing the radiator fins. I installed new motor mounts and a new trans mount but also had to modify the panel that goes across the radiator. I made the holes for the upper radiator studs oblong so I could lean the radiator forward just slightly. This combination finally fixed my rubbing issues.
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Unread 05-07-2013, 07:55 AM   #37
KF4SQB
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I'd say that the suggestion someone gave you about the slip yoke/output shaft splines hanging is possible. Under acceleration, the rear of the vehicle tends to "squat". This causes a small reduction in distance between the differential and the rear of the transmission/transfer case. This change is distance is usually compensated for by the slip yoke sliding on the splines on the output shaft; thus the reason for the slip yoke. If the slip yoke is frozen to the output shaft, it can't compensate. The differential is pretty securely mounted, by the leaf springs, so it can't move much. The engine/transmission assembly is mounted on rubber, so its easier to move, so it moves to compensate. I was going to suggest that the radiator core support was moving to the rear under acceleration, until you said that it happens with it in gear, brakes held, and revved up. This will also cause the same rear squat that heavy acceleration causes. I'd look at that slip yoke/output shaft interface. With the drive shaft disconnected from the differential, the slip yoke should slide in and out of the rear of the transmission/transfer case very easily.
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Unread 05-07-2013, 09:31 AM   #38
97hero
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I will check on the slip yoke/output shaft as soon as I can, shouldnt be that hard to remove and take a look right?...if this is the case is this something that would just need greased and reinstalled or is it a more involved project?
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Unread 05-07-2013, 09:49 AM   #39
KF4SQB
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If everythings right, its not at all hard to remove. You'll have to unbolt the driveshaft from the differential yoke, just remove four bolts, then the straps will come off, and the u-joint will come out of the yoke. If the slip yoke at the back of the transmission/transfer case is frozen, you will probably have a hard time getting the u-joint out of the differential yoke, as the driveshaft has to move forward to do so. If the driveshaft moves forward easily when you try to remove the u-joint, thats not your problem. If the driveshaft won't move forward to let you remove the u-joint from the yoke, you may have to jack up the frame of the vehicle, without jacking up the rear axle, to allow the axle to drop and give you some slack. If it is frozen, once you get it out, it should be a simple matter of cleaning the splines on both parts, adding a little ATF (or gear oil for a manual transmission w/o transfer case) to them before reassembly, and putting it back together. You will have to drain your ATF (or gear oil from a manual transmission w/o transfer case) from the transmission/transfer case, and remove the tailshaft housing to clean the splines on the output shaft. Shouldn't be more than a couple of hours worth of work.
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Unread 05-07-2013, 10:06 AM   #40
97hero
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What all should I need for this job?
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Unread 05-07-2013, 11:21 AM   #41
KF4SQB
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Worse case scenario, a few different sizes of wrench (sorry, don't know sizes), a drain-pan, a jack, jackstands/cribbing, a hammer (to gently tap the slip yoke to get it moving, if frozen), possibly a pry-bar, tape/old sock/rag (to tie/wrap around the u-joint at the differential end of the driveshaft so the cups don't fall off after removal from the differential yoke), something to chock the wheels before removing the driveshaft, a wire brush & screwdriver (to clean out the splines), ATF or gear oil (depending on your setup), a few rags, and a few beers. It would also be a good time to change the rear seal in the transmission/transfer case if its showing signs of leaking.
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Unread 05-07-2013, 11:28 AM   #42
97hero
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Thanks for all the info and the list of things I'll need...I will be tackling this saturday, hopefully this is the problem and I can get it fixed this weekend...its been drivin me crazy tryin to figure this out. Thanks again!!
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Unread 05-07-2013, 05:32 PM   #43
habbyguy
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On my '96, the bolts that hold on the rear U-joint are 10mm. Just make sure and mark how the U-joint is aligned in the carrier when you take it out so you can get it back in the same way.

Maybe I'm missing something, but why do you have to drain the tranny fluid to remove and lube the drive shaft? There's no reason in the world to do that I can think of (other than as part of regular maintenance, of course).

Pulling and lubing the slip joint should be a 10 minute job if it's not frozen in place (which it may well be, of course). Four 10mm bolts out, pull the drive shaft slightly forward (if it'll move, that is...) and drop the rear and pull it back. Clean, lube and re-install.
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Unread 05-07-2013, 05:48 PM   #44
KF4SQB
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That's for if the slip yoke is frozen to the output shaft. If it is, the output shaft splines need to be cleaned, and that will require removing the tailshaft housing. If its frozen, and its not cleaned properly, it will freeze back up fairly quickly. If it moves freely, there's no reason to disassemble.
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Unread 05-07-2013, 05:54 PM   #45
KF4SQB
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That's for if the slip yoke is frozen to the output shaft. If its frozen, and the splines aren't cleaned properly, it will most likely freeze back up fairly quickly. There's not much way to properly clean the output shaft splines without removing the tailshaft housing. If it already moves freely, there's no reason to disassemble.
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