My transfer case 4404 has bearing noise on the front end, please help!!

[93explorereb]

Greetings:

Does anyone know as to how extensive a job it is, to replace the transfer case bearings and seals? My transfer case seems to be making some bearing noises, each and or everytime I accelerate. Its like a bad diff howling sound. Both of my diffs are ok. Would the transfer case need to be removed to replace the seals and or the bearings. In other words, does one have to dismantle the entire case? I have no leaks or nothing, just the howling, and light grinding. Right now my front shaft is off. Is the case safe from any damage while the front diff is off? I need another shaft (6 bolt flange), whereas the CV joint end of the shaft is no good. What say you? I have since changed the transfer case fluid (Valvoline MaxLife Dexron/Merc ATF). Black ATF drained out. Please help!!! Thanks in advance!!
1997 explorer XLT AWD 5.0 V8
123,000 ORIGINAL MILES

Best Regards

 

[gavin]

couple of things... first, the noise is gone with the front driveshaft removed, correct?

chances are much higher it's the cv-joint end of the d-shaft that's causing the racket. Plenty of people have had this issue, thinking it was their t-case.

also:
BW4404 rebuild
http://www.explorerforum.com/forums/showthread.php?t=218430

mroe about the BW4404 and viscous coupling
http://www.explorerforum.com/forums/showthread.php?t=225515

 

[93explorereb]

couple of things... first, the noise is gone with the front driveshaft removed, correct?

chances are much higher it's the cv-joint end of the d-shaft that's causing the racket. Plenty of people have had this issue, thinking it was their t-case.

also:
BW4404 rebuild
http://www.explorerforum.com/forums/showthread.php?t=218430

mroe about the BW4404 and viscous coupling
http://www.explorerforum.com/forums/showthread.php?t=225515

hey Gavin! Yeah the front shaft has been removed, however, I still get somewhat of a howling sound, within the vicinity of where the front shaft connected to the transfer case. Although it is nowhere as pronouced as when the shaft was connected, it still crops up, when I tend to accelerate. It is a low pitched howling whining sound, similar to a bad diff at the begining stages. I have changed the transfer case fluid, but I am thinking inner/outer transfer case bearings? I feel and or hear this sound, just underneath my feet on the driver's side of the truck. Funny thing is, at the same time my ABS systems has been overly sensitive, whereas as I brake, it often kicks in on dry payment. I replaced my driver's side front hub bearing, and I am going to replace the passenger's side sometime on the weekend. Either way I love the truck, and have plenty of patience in correcting the problem, however, my time is limited. Thanks Gavin!!


Best Regards

 

[93explorereb]

excellent writeups Gavin! I take it when you case goes and you can hear that chain in the case, then your in trouble! Is it possible for those inner bearings to be the culprit? Would I have to take the transfer case out of the truck to replace them? Thanks!

 

[gavin]

sounds like you may have a couple different issues, but hard to say for sure.

I would double-check the u-joints on the rear shaft also.

yes, if the chain breaks, you're pretty much stranded.

It's very possible it is a bearing inside the case; none of these can be replaced without tearing the case apart, as the front output shaft is held in place by a cir-clip.

As for damaging the case with the front shaft removed; nobody is 100% positive that it can damage anything. There is a very good possibility that this can cause premature wear on the viscous coupling, but many people have drove several thousand miles without the front shaft, with no noticeable side effects (myself included; I did replace my VC, thinking I killed it, but there were no noticeable differences after replacing. I had put on ~5000+ miles with the front shaft removed).

 

[93explorereb]

sounds like you may have a couple different issues, but hard to say for sure.

I would double-check the u-joints on the rear shaft also.

yes, if the chain breaks, you're pretty much stranded.

It's very possible it is a bearing inside the case; none of these can be replaced without tearing the case apart, as the front output shaft is held in place by a cir-clip.

As for damaging the case with the front shaft removed; nobody is 100% positive that it can damage anything. There is a very good possibility that this can cause premature wear on the viscous coupling, but many people have drove several thousand miles without the front shaft, with no noticeable side effects (myself included; I did replace my VC, thinking I killed it, but there were no noticeable differences after replacing. I had put on ~5000+ miles with the front shaft removed).

Wow! Thanks! Yeah I am thinking that the noise is coming from the transfer case shaft connection for the front shaft. I sort tugged on the cup end section on the front of the transfer case front shaft connect, and it has some play in it. It can be slightly pulled forward and slightly pivots back into place. However, upon trying to wiggle it say from 9 o' clock to 3 o' clock and or from 12 o'clock to 6 o'clock, it doesn't exhibit any sort of play whatsoever. I think it maybe be the bearing and or bearings just inside this area. Now my front shaft CV joint end/shaft, can it be reused? The only visible issue was that the cv cup end was detached from the shaft. It sort of separated via rubber clamp seal boot. Could I get another similar shaft off of a 4wd version of the same explorer, or does this shaft have to be from an AWD 6 BOLT FLANGE SETUP LIKE MINE? Thanks again Gavin, you have been extremely helpful!!

 

[gavin]

there will be slight fore/aft play in the front output flange.
it's only held in by a circlip, so there must be some play, otherwise the circlip would get worn down to nothing.

Only the CV-style driveshaft can be used up front on an AWD.
Due to the pinion and t-case angles, even a double-cardan shaft will exhibit vibrations above ~40mph. So it must be the same style. If the boot is ripped on yours, I recommend getting a new one. Otherwise you could rebuild your existing one, but look at spending roughly the same amount of money on a new cv-joint and labor. ericautopart here can get you one for a very reasonable price, but still look at spending ~$200 or so (iirc).

However, upon trying to wiggle it say from 9 o' clock to 3 o' clock and or from 12 o'clock to 6 o'clock, it doesn't exhibit any sort of play whatsoever.

do you mean applying upward/downward/sideways pressure? As in, pushing it up, pulling it down? If yes, and there is no play there, chances are the front output shaft bearings (yes, there are 2 bearings for the front output shaft), are good.

I would start with replacing your dri. side hub/bearing assy first, since you said you were going to anyway. There's a good chance that could be where the "howling" is coming from.

 

[93explorereb]

there will be slight fore/aft play in the front output flange.
it's only held in by a circlip, so there must be some play, otherwise the circlip would get worn down to nothing.

Only the CV-style driveshaft can be used up front on an AWD.
Due to the pinion and t-case angles, even a double-cardan shaft will exhibit vibrations above ~40mph. So it must be the same style. If the boot is ripped on yours, I recommend getting a new one. Otherwise you could rebuild your existing one, but look at spending roughly the same amount of money on a new cv-joint and labor. ericautopart here can get you one for a very reasonable price, but still look at spending ~$200 or so (iirc). Thanks Gavin! so far it appears that the bearings are good. The hub bearing on the passenger's side is next. I did the driver's side a few weeks ago. Yeah on the flange I can pull it slightly in and out. But up and down or side to side, its tight no movement!! I will keep you updated. And thanks again!



do you mean applying upward/downward/sideways pressure? As in, pushing it up, pulling it down? If yes, and there is no play there, chances are the front output shaft bearings (yes, there are 2 bearings for the front output shaft), are good.

I would start with replacing your dri. side hub/bearing assy first, since you said you were going to anyway. There's a good chance that could be where the "howling" is coming from.

 

[93explorereb]

there will be slight fore/aft play in the front output flange.
it's only held in by a circlip, so there must be some play, otherwise the circlip would get worn down to nothing.

Only the CV-style driveshaft can be used up front on an AWD.
Due to the pinion and t-case angles, even a double-cardan shaft will exhibit vibrations above ~40mph. So it must be the same style. If the boot is ripped on yours, I recommend getting a new one. Otherwise you could rebuild your existing one, but look at spending roughly the same amount of money on a new cv-joint and labor. ericautopart here can get you one for a very reasonable price, but still look at spending ~$200 or so (iirc). Thanks Gavin! so far it appears that the bearings are good. The hub bearing on the passenger's side is next.


I did the driver's side a few weeks ago. Yeah on the flange I can pull it slightly in and out. But up and down or side to side, its tight no movement!! I will keep you updated. And thanks again!



do you mean applying upward/downward/sideways pressure? As in, pushing it up, pulling it down? If yes, and there is no play there, chances are the front output shaft bearings (yes, there are 2 bearings for the front output shaft), are good.

I would start with replacing your dri. side hub/bearing assy first, since you said you were going to anyway. There's a good chance that could be where the "howling" is coming from.

I did the driver's side a few weeks ago. Yeah on the flange I can pull it slightly in and out. but up and down and or side to side, and it remains tight, no movement I will keep you updated. And thanks again for all of your help!

 

[93explorereb]

I replaced the other front hub bearing on the passenger's side. And the brake work better than ever. Also I no longer recieve that constant ABS pulsating pedal every five seconds. So the hub was no good and or on its way. I also replaced the front rotor too! However, that slight whine/howling is still there. I am going to replace the rear brake pads and rotors tommorow morning. Hopefully a rotor is out of round and or warped? Or maybe a caliper is sticking? I sprayed the u-joints with some PB Blaster. Ironically, the sound becomes more pronounced upon the level of accleration.

 

[93explorereb]

Might my cv joints be seizing up? I do not recieve any clicking noises upon any turning or anything.

 

[gavin]

spraying u-joints with pb blaster won't do any good

do you have an accompanying vibration with the noise?

 

[93explorereb]

spraying u-joints with pb blaster won't do any good

do you have an accompanying vibration with the noise?

Thanks, Gavin! No just low pitched whining, howling, sort of like a bad diff type of sound. I am going to do the rear brake pads/rotors today. Also I am going to replace the rear stabilizer axle shock. I will also check the rear diff too.

 

[jpablogc]

noise...

Hi guys,
can you please tell me the difference between transfer noise and wheel hub bearing noise? i ask that beacause aloca shop guy told me "your bearings are on its way, be carefull..." but....i just got my 97explorer. 4.0lts ohv a month ago from a guy that,when asked about that noise,answered "well,i´ve had this car about year and a half , and it always made that noise...!! "
Can a broke bearing work that long??