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Transmission woes -- advice needed

T

tx_murray

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My 1996 LT-4 had a new clutch (Centerforce Dual Friction) installed last week by Corvettes of Dallas in Carrollton, TX. While they had the transmission out they also replaced the rear main seal. After driving the car home (about 30 miles), I noticed the smell of burnng tranmission fluid. Looking under the car revealed a few fresh drops of fluid on the exhaust, directly under the center of the car. Before the tranmisssion work, my car had NO fluid leaks whatsoever.

I took the car back to Corvettes of Dallas. They examined it and told me that the fluid leak was coming from the speedometer sensor on the transmission. They then installed a new sensor and added more transmission fluid. I took the car home, and much to my dismay found the car still leaking in the same spot.

I took the car back again yesterday. They told me they spent 8 more hours of labor on the car taking apart the transmission again and replacing the input shaft seal. They then drove it about 20 miles, put it back on the lift and said it was "bone dry." I picked the car up, brought it home, and guess what? The smell of burning transmission fluid was back, along with fresh drops of transmission fluid on my exhaust.

The question is what now? Any suggestions? I've already spent $1200+ with Corvettes of Dallas, and they are telling me "we can't find the leak." Should I demand that it be fixed properly, which is what I paid for and expect, or should I give up with them and go spend more money at a Chevy dealer? Anybody have any similar problems?

Thanks,
Randall
;help
 

Ken

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tx_murray said:
My 1996 LT-4 had a new clutch (Centerforce Dual Friction) installed last week by Corvettes of Dallas in Carrollton, TX. While they had the transmission out they also replaced the rear main seal. ...Before the tranmisssion work, my car had NO fluid leaks whatsoever.

Should I demand that it be fixed properly, which is what I paid for and expect...

Randall, demand satisfaction if what you say about there being no leaks whatsoever is true; they screwed something up from the sound of it.

Last year when I was still throwing money my DN 4+3, the speedometer o-ring they used was a flat unit when the service requires a round o-ring. I lost all of my trans fluid from the OD and burned it up. :(

Good luck, and stand up for your rights. Remember the Alamo!

_ken :w
 
R

ROCKO

Guest
Your leak

I can't help you with the leak but I sure can give you some support. Whenever any work is done my Vette other than by my self I always demand within reason that the job be performed satifactory. Remember it's your money. I'm sure you work hard for it. Demand satifaction. If the car did not leak before service it should not leak after. If your like me I can't stand leaks. My Vette has 143k and does not leak one drop. The engine compartment looks factory new. Go get your satifaction.

Rocko:bang
 

vigman

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Here's how I would approach it.

1)Take a pix of your driveway where you normally park the car..showing only the NEW spots.

2) In a manual tranny there are only a FEW places where the oil can leak, take the car for a FREE brake inspection at Midas..or someplace like that,
get the car in the air... and YOU take a look under the car, see if you can see where the leak is. Get the person writing you brake inspection to note this as well.

3) Present a letter ( with copies of this info ) to the service manager.. and state your FACTS, see what they would be willing to do.

Now that being said.. if your tail shaft is leaking.
( which I'm betting the problem is )
You will have to pay for that PART but not the labor, since they missed it the first time.. usualy it gets torn up a bit putting the trans back in.

The other thing are the side case seals.. they could be old as well and seeping..

How old is this car & how many miles are on it?

We are talking about tranny fluid, not engine oil correct?

My .02

Mike
 
T

tx_murray

Guest
Re: Here's how I would approach it.

vigman said:
How old is this car & how many miles are on it?

We are talking about tranny fluid, not engine oil correct?

My .02

Mike [/B]


Thanks for the advice. The car is a '96 with 63,500 miles on it. There were absolutely NO leaks anwhere on the car before the work was done. It is definitely transmission fluid, not oil.

How much would a tail shaft cost me?

-randall
 

vigman

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Tail shaft seal

Sorry....the seal is 20-30 bucks MAX, its what allows the driveshaft nose to spin in the tail of the tranny WITHOUT leaking. It's however a pretty labor intensive job to get to it Exhaust has to come out AGAIN, driveshaft has to drop and bingo
there it is.

The seal has a spring around the the round part which compresses against the output shaft, this SOMETIMES makes a groove in the output shaft, not making a perfect seal. The rubber gets hard and once you pull the shaft out ( to drop the tranny ) and put it back in it doesn't seal as well again.

Most GOOD tranny guys will offer to reseal the tranny once it's out ( for an additional charge ).
Like the rear main.

But I suspect this was a wham bam, now they get to do it again & again. the cost of the seal kit (I'm guessing here) is less than 100.00 for ALL seals, and you've done the input seal already.

Mike
 
T

tx_murray

Guest
tail shaft seal

Thanks everyone for the advice and suggestions.

I should also mention that the service manager told me they found a "metal chip" loose in the tranny. They didn't know what it was or where it came from.

So what all seals are there on the tranny? Sounds like:
- tail shaft seal (a.k.a. output shaft seal?)
- input shaft seal
- side case seals
- speedometer sensor seal
- Any others?

I'm not a mechanic, but it seems to me you'd want to replace all of them when dropping and reinstalling the transmission.

-Randall
:mad
 

vigman

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They ALWAYS say that stuff!

Well however that works in your favor.

How did they FIND the metal chip.. did they UNSEAL the tranny? where did they find the chip? Have them show you the chip ( have a magnet in your pocket ready) if it's bigger than the drain hole & magnetic...and it dosen't show a case seperation in your service record.

your probably getting BS'ed

*note
there is a round magnet in the bottom of the two cases to collect metal bits.

( READING IN THE BOOK )

There is NO SIDE CASE..AH HA!
The shift linkage is a toploader on the ZF 6 speed

Area's where oil can leak..

There is the side cover for the changing of the speedo gears( gasket )

Speed sensor oil ring

Rear oil seal (a.k.a. output shaft seal?)

There is a solonoid coming into the side of the case 1-to 4 lockout ( right side)

The backup switch.( right side)

Input shaft seal.
Countershaft seal ( under input shaft seal )

There a vent on the top of the tranny with a pipe
( that goes up higher.. to avoid fumes & allows the tranny to vent) ventilator cap & tube.

The case seals ( which shouldn't have been touched, these hold the 3 pieces of the case together).

Fill plug (right side of case)

Drain plug.. (bottom of case)

Phew
That will be 350.00 sir...how would you,like to pay for that? LOL

Mike
 

vms4evr

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Randall,
If they are telling you it's the speedo sensor then they either crushed the o-ring or screwed up the sensor. I just had my rear gears done. To do so required dropping the tail housing and putting in new speedo gears and sensor. They replaced all the seals and gaskets. I watched them. It wasn't complicated and it is sealed up tight. It shouldn't be leaking. I agree with the guys. You just sank a bunch of money into their shop. It should have been done right and the work should be guaranteed.
Mike makes a good point too. Get it checked at another shop. Just to see where the fluid is coming from and that it is actually leaking tranny fluid and have them write it up.
Good luck! Hope it gets worked out.
Graham
 
T

tx_murray

Guest
The latest

Now I'm being told that the problem MUST be a hairline crack in the tail shaft housing. Chevrolet told me the part is $683! Any thoughts on this possible fix?

-Randall
 

69MyWay

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Randall,

I replaced the clutch myself on our old 89 six speed. Amost exactly the same job as it would be on your 96. At the same time I replaced the clutch I replaced the rear seal.

Anyway, I know that stinky smell you are talking about. It is aweful.

Our problem turned out to be rather simple. The rear seal where the drive shaft slips into the trans had blown. It would leak just enough to stink like heck. GL (trans fluid) smells bad to begin with, but really stinks when it burns. The gear oil in the ZF is like 5W30 motor oil and will easily leak out of a weak seal.

At the time we had about 72,000 on the car.

By the way. One day it was fine. The next day we are driving down the road and stopped at a light. The cloud of stink caught up to us. I thought it had to be another car in traffic because ours surely did not have such a problem.

If it is the rear seal it is going to be hard to prove that the shop was at fault in anyway.

These things get tricky to resolve.

Now a cracked rear tail housing would make me wonder if they dropped the trans during the clutch swap. You usually don't crack a rear housing unless you really thrash the car with some redline clutch dumps, or physically whack the trans on something.

Could be the fellow that test drove it for the shop had a little fun at your expense.
 

vigman

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Have em put the car in the AIR

And SHOW YOU !

Does it show on your work order that the rear oil seal was replaced?

Mike
 
T

tx_murray

Guest
Re: Have em put the car in the AIR

vigman said:
And SHOW YOU !

Does it show on your work order that the rear oil seal was replaced?

Mike

Yes, they replaced the "rear main oil seal" according to the receipt.

Is there any way to diagnose a hairline crack in the tail shaft housing without GUESSING that is the problem?
 

vigman

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Well yes

You can see most of it from underneath..

However it will be hard to prove that they DIDNT mess it up unless

You can see fresh pound marks ( from hammer or tool strikes or a fresh flat mark from dropping it ) on the tail housing.

Or

The last time it was serviced ( Like Jiffy lube) where they inspect the car for leaks.. to try to sell you stuff ( engine sealer etc ).. but the do write down the condition that they find at the time.

How much oil does it leak overnight ????

Size of a quarter? 50 cent piece? Lake Huron?

If it's a TINY leak... They might do a J&B epoxy weld job on it.

"Now I'm being told that the problem MUST be a hairline crack in the tail shaft housing"

This sounds like their guessing.... the only way to find out is to look!

Mike
 
T

tx_murray

Guest
Re: Well yes

vigman said:
[BHow much oil does it leak overnight ????

Size of a quarter? 50 cent piece? Lake Huron?

If it's a TINY leak... They might do a J&B epoxy weld job on it.

Mike [/B]

It leaks about the size of a quarter overnight, in 1-3 spots. The fluid is getting thrown around while driving and ends up on the exhaust in various places, then drips down.

They are checking into taking the tailshaft housing to a specialty tranny shop to have it pressure tested to see if there is a leak.
 

vigman

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WHATTTTTT?

I'm smelling rats here....

How will they do that?? have him explain that IN DETAIL.. start taking notes... get things in writing....

Are they pressure testing JUST the tail shaft housing.. or the whole tranny....?

I'm assuming they have the car back?


Mike
 

vigman

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Any news update?

Enquiring minds want to know!

Mike
 
T

tx_murray

Guest
Update

Corvettes of Dallas is convinced that my tail shaft housing is cracked, and they have ordered a new one to replace mine. Hopefully this week I'll have the car back as it once was, with NO LEAKS. I am being charged almost $700 to replace the tail shaft housing. I got a second opionion from a transmission shop before consenting to its replacement. What I thought would be a simple clucth replacement job has turned into a $2000+ nightmare. I hope this is the last bit of maintenance the car will need for quite some time.

-Randall
 

vigman

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And

Assuming from the price tag your footing the bill for the new tailshaft?

Did the 2nd shop look at it?
What did they say ( assuming again bad news since the 1st shop got it back.)

Insist on the reciept from the dealer showing it's a NEW tailshaft.

I would clean it's parking spot.
Take pictures.
Get people to notice that it is clean.

And watch like a hawk!

Mike
 
T

tx_murray

Guest
2nd opinion

After a quick glance with the car on the lift, the other shop thought it was fluid leaking from the shifter boot. That turned out to not be the case--the shifter boot was dry inside. It was wet from the wind blowing fluid from the real leak.

I am having to buy the tail shaft cover, but at the shop's cost and with reduced labor charges.

I'll keep you posted on the results.
-Randall
 

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