T-case woes BWQT HELP?

[jode]

In the continuing saga of the POS BW QT....

Background - when I punch it on the street I get a clunking sound from the T-case that seems as though it is tearing the POO out of something, but I have been driving it (progressively getting worse) like this for months. No shops can idesntifuy it and the only true way ( I am beginning to think) is to pull the SOB and have a looksee (which is in the plans for sometime soon)

However, I have a new discovery that may shed some light on the subject.

When in normal gear, she will make the popping sound off the line. When in low range, (reduction unit engaged) she is even worse...as in it is hard to ease the gas pedal down slow enough to not make the engine produce too much power and make her pop.

SOOOOOoooo, I am thinking that it CANNOT be the output shaft of the transmission...here's why..
if it were the transmission, then gearing down (as when the reduction unit is engaged) would increase the leverage that the engine had on the wheels (each revolution in the engine equates to less distance traveled at the tires) which would mean that the output shaft would be transmitting less force in order to get the truck started. S :( o that popping sound should be decreased when I am in low-range if the tranny output were the culprit right?

Hope fully that logic makes sense.

One other lead (aside from the T-case
chain) that I am following (that my new theory supports) is that there is a 10" long splined driveshaft in the reduction unit that they say may be bad.

Anyone have any thoughts?

[porkchop]

It is your chain. I had the same thing when I was running my QT. Changed out the chain and all is good.

[blt2krl]

Totally sounds like your chain like pc said. I believe a new chain is right around $100.

[illegalFSJ]

I know 2 others have already said this but: It's your CHAIN! I had the exact same thing on my '77 and '79 wagooneers. The mechanic's don't know, and they'll charge you $100 just to diagnose it, and they'll probably be wrong anyway!. I did it myself on both my trucks and it solved the problem perfectly. It dosen't even take very long. You just unbolt the 'case remove the rear cover, take out the two gears and chain, slap on a new chain, slam it all back together, put in new QT fluid, and yer set!

[Rob]

When I had the same, everybody also said "it's your chain". I replaced it but the noise was still there. It turned out to be the clutch and brake cones in the QT's centerdiff. :( :( :(

So check your chain first before you order a new one. It's an easy check. Take out the upper plug on the QT. Then with a screwdriver you can reach the chain and feel the play by moving it up and down. If the play is 3/4" your chain is OK. At 1" you should start to worry and with 11/4" of play you know it's definately your chain !

[jode]

I just replaced the chain!!!!!
Sorry I guess I forgot to mention that. I replaced it and it was no good. I did use a JC Whitney chain of questionable origin, though...but what are the chances that it was so crappy that it was IMMEDIATLEY worthless?

PS...a word of advice....AVOID THE $100 CHAIN!
If my prob turns out to be the chain, JCW can eat a big fat &*(%

Originally posted by Rob:
It turned out to be the clutch and brake cones in the QT's centerdiffROB! Tell me more....your solution doesn't seem to make sense seeing as those cones shouldn't be actuated during a straight-line startup...right?
What is the logic in it being the cones? Mine makes the noise WHENEVER i hit the gas (very hard) and it does it when I'm going straight! As far as I know, the cones only serve as the limited slip function of the center differential.

Riverbeast...you out there?

BTW to all the folks that said chain...doesn't the "discovery" in my original post seem to point to the theory that it is not the chain? Read it again.

[ June 11, 2002, 12:30 PM: Message edited by: jode ]

[River Beast]

Rep... I'm here... ;)

I helped Rob out with his...

go to my site and look at eh QT page I have... the front brakecone splines are stripped out... that's what Rob is talking about...

Lock it in E-drive... it may still do it (splines still have to grab something).... now remove the front shaft and lock in E-drive... noise goes away... that will tell you it's the front brakecone in the center diff of the QT...

This is time consuming, but doesn't cost you a dime until you figure it out...

[jode]

Dangumit! I tried already taking off the rear shaft and driving in E-drive (still clunks), but that dadbern front shaft is gonna be a serious PITA PITA PITA! You see, I had a 3" exhasut systme installed and they routed the tube right under the front doublecardan joint. I seriously can't see how Im gonna get a wrench in there without tearing apart the exhaust (which I don wanna do).

RB I saw the site and see the damage, but I have to go back to my original question of "what is the logic behind a brakecone making noise on a straight-ahead start wiht no turning involved?"

What about the reduction unit spline shaft? Anyone heard of one stripping out?

BTW she pops in E-drive or not...same dif.

Luckily I have access to a near-free QT unit, but I would prefer to repair mine seeing as it has a new chain and I know (aside from the problem) that everything else works in it. I'll try the front shaft-off-idea although I really don't want to and then, if no dice, will go the route of the replacment case. (of course when I go that route, I will tear apart the exising case to ascertain the gremlins.

Another question...when splitting the BWQT, is it necessasry to use a new gasket (the big O-ring) to reseal the halves, or would a good dab O RTV do the trick?

[River Beast]

The reduction unit is driven by the TH400 output 10 spline shaft... I just sold the only one I had.

Now the brakecone are consistantly having pressure... regardless of turning or a straight line.. that is why it is IMPERATIVE to have all the same size tires with equal pressure on all four... any variance and it will cause the brakecone to start slipping due to unmatch tires from front to rear or unequal pressure... constanst driving like this will cause premature death to the brakecones... mainly the front one (I dunno why just the front).

The reason she is popping in E-drive (rear shaft removed or not) is most likely the front brakecone...to verify this the front shaft MUST come off and retest in E-drive.

IF the popping is still there... now you start looking the the TH400 output shaft.... they are a course 10 spline shaft... as you prolly already know.

When you did your chain, did you inspect the output shaft?... if the splines on it are rounded, then most likely so is the mating gear slines in the reduction unit.

I know this can be frustrating... I'm sorry... but the more you do to diagnose the pinpoint the problem PRIOR to spending $$$$ the better off you will feel and be in the end...

Nothing worse than spending $400 on parts not needed to find out that it should have only cost you $100..if you took the time (not money) to troublehshoot thoroughly.. I have a few of those T-Shirts... :D

Keep us posted... and I'll be here as usual... ;)

DON'T GIVE UP!!!! IF you reach your wits end.... take a break and lay off it a while.... no use working yourself up and getting even hotter under the collar....

We are with you ... we'll figure this out....

[jode]

I follow advice of Zen master

:D

[Rob]

Couldn't you loosen the front drive shaft at the other end? At the front axle diff. Just for testing that shouldn't make any difference? Or am I wrong?

[jode]

Hmmm...very interesting....yes and hang the DL in a loop or something...jsut for testing....good idea! Thanks

[Rob]

Yes, That's what i meant. Just be careful, that it can turn freely.

[River Beast]

Grasshopper must enighten us on the outcome of his journey.... ;)

Yeah.. be careful letting the DL hang free while testing.... I would hate for you to take out the corner of your TH400 at the pan... :eek:

[jode]

Well Zen followers, Grasshopper has been pooed upon. :eek:

I took off the front driveline and she still clunks under torque! It's more of a sharp sound now though than the clunk of before. So I've had both DLs off at different times and still get the clunk....it's really starting to look like a different stripped shaft...I'm hoping it aint the tranny though :(
We'll see what happens when I get the T-case outta there...as I said...if it's that JCW chain, I'm fixin to throw a fit...as a matter of fact...maybe I'll check it tomorrow :D

[River Beast]

Sorry to hear this news Jode.... let us know when you get it out...

[JEEPGUZZZI]

You don't , by chance have a part-time kit installed, do you? I was once given the wrong chain. I have the 16% overdrive and the goof of a mechanic ignored what I told him and installed a regular chain. Guess what? Acted like yours. Just thought I'd throw that out there.
P.S. I got my $100 dollar chain from Jeepdoc.com Made by Morse, and shipped by a guy with over 30 years of Jeep experience. ;)

[wn]

I had the exact same problem and it was solved with a transfer case rebuild which included a chain and replacing a worn gear on a shaft. (don't know the technical name) The gear was turning on the shaft and slipping.

This also, corrected my transfer case from popping into neutral. Total rebuild was 386.00 parts and labor and 1 year warranty. Works like a charm now.

[porkchop]

Did you put on the new chain? If so how hard was it? It should not just go right on, at least the one I did didn't I had to fight with it to get it one. Once I did my popping was gone.

I know this is fustrating. I am on the vurge of selling mine too with all the carb problems I am having. So please hang in there and remember we are only trying to help.

[jode]

No it aint the OD case and unless they sent me the wrong chain (shoulda counted links I guess) then it should be right.
Yes I installed the cahin and yes it was a beeatch. But then again, maybe it is sposed to be even more of a PITA than it was :eek: who klnows?

I'll have more info after I tear her apart...

Thanks for all the advice...it was appreciated (even though I haven't got an answer yet :D )

Grasshopper continues down the path to enlightenment!

[jode]

On second thought...now that I've driven around in e drive for a while with no front DL, maybe it is a LITTLE bit better.

Could it be that I circumvented the problem, but am now getting slippage through the brake cones?

[River Beast]

With E-drive locked... there is no slippage UNLESS the splines are gone...

You need to disassemble it.....this is my opinion.

There is LOTS of slop with one shaft removed and in E-drive... this I know.. I drove that way for over a year.