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Transmission woes -- advice needed

Sometimes that is just how these kind of things go. As you know I am doing a six speed clutch change right now myself. In my case I have ditched the heavy dual mass flywheel in favor of a lighter one piece, a RAM brand high friction clutch, and a new six speed pressure plate. This kit comes with a special ball stud to reset the position of the clutch fork to make up the difference in flywheel thickness.

Anyway, I planned on initially spending about $300 for the conversion as the clutch disc and ball stud kit is $250, and I figured I would round up a used $50 1987-1988 4+3 vette flywheel.

Well, $250 for the kit, $220 for a NEW flywheel from G.M. (beats $800 for a new dual mass unit), and $220 for a new pressure plate as my old one had some serious signs of wear.

So, I totally blew the original budget, and I have yet to finish the job. So, if I break anything going back in, the cost just goes up.

Hang in there, they will get you straight eventually. I still have my doubts as well about a cracked housing, but stranger things have happened.
 
Go for the throat...

I thought stuff like this only happened to me. I can't give you the tech advice but biz wise - if you charged the repair you got a leg to stand on. Request a charge back and provide your documentation. I have one pending on a starter that I was sold and didn't need. It's certainly worth the try.
jj
 
Another thing, nothing says a dealer could do the job any better. I have been to 3 dealers in town (2 of which sponsor vette clubs) and none of them have been able to do a job right the first time. One was not able to fix or find the problem, the other, well I think it is ok now, but it has been back at least 5 times for one thing or another.

If the new tail cone does not fix the leak, don't pay for the part or the labor for it. They are "part swapping."

Best of luck.

MIke
 
Update

I lost faith in Corvettes of Dallas (after having it there 3 times) and decided to take my car to the local Chevy dealer. They diagnosed the same problem, a cracked tail shaft housing, plus another minor seal leak on the tranny. I don't know how the housing cracked, and I won't point any fingers of blame, but everyone I talk to about it says that it is extremely rare that a tail shaft housing cracks. Either something went wrong during the repairs or I was just very unlucky this time.

From now on my car will go only to the dealer for repairs.

The dealer ordered the part from Lansing, MI. I should have the car back early next week; I can't wait. I can only drive my Camry for so long before having Vette withdrawls! :s

-Randall
 
I have thrashed several transmissions
in my younger years,never hurt a tail housing. If it has a new crack it is because they dropped it or
just didn't assemble something right.
Sounds like they may have put a rookie mechanic on this job?? A tail housing seal is not that hard to install. If you hammer it in, it can get messed up. If they put in a new one and did not use any lubricant on the seal or driveshaft yolk, it could burn up the seal. They need to fix this to your satisfaction. A big leak is not right.
A small leak is not right after you spend that kind of money.
 
Your a better man that I

I would have those Good Ol' Boys
Glued,Tattooed & SCR well you get the idea!

can you get a picture of the old tailshaft when it comes out?

maybe there will be some recourse that you can take!

Let us know when you get your baby back,I'm interested in the outcome!

Mike
 
Randall,

Tail shafts crack from extreme duty use (thrashing the &^&*% out of the car), poor quality casting, and of course being dropped or struck with significant force.

My 69 with the Muncie had a tail shaft crack in a prior life. I don't know how, or when, but when I yanked the old girl out of the car and cleaned it up I found a huge aluminum weld going around 3/4 of the tail shaft housing. My local four speed experts told me what I said above in terms of the most likely cause.

Now, a C4 has a special torque arm that bolts with two long large bolts at each end (two into the tail housing, and two into the front of the differential). It is entirely possible that the tech used a pry bar to push, wedge, force the torque arm back over the tail housing, then used an impact wrench with way too much air pressure to torque it all down. That would have caused a crack without a doubt.

My money at this point is on an improper install, and too tight of a torque on the tail shaft bolts. Because, a C4 uses the torque arm, it is almost impossible to cause damage to the tail shaft from thrashing the throttle and dumping the clutch. A C3 and most other cars would be a different story since they don't have that torque tunnel arm.

Don't know if I am helping or hurting your case here, but having just finished slamming my ZF6 into the car this week, I feel like a little bit of an expert on the subject (at least in my own mind!)


Good luck.
 
Chris brings up a good point here!!!

Have you actually seen the the tail shaft crack?

Where exactly is the crack?

Mike
 
69MyWay said:
Randall,

Now, a C4 has a special torque arm that bolts with two long large bolts at each end (two into the tail housing, and two into the front of the differential). It is entirely possible that the tech used a pry bar to push, wedge, force the torque arm back over the tail housing, then used an impact wrench with way too much air pressure to torque it all down. That would have caused a crack without a doubt.

My money at this point is on an improper install, and too tight of a torque on the tail shaft bolts. Because, a C4 uses the torque arm, it is almost impossible to cause damage to the tail shaft from thrashing the throttle and dumping the clutch. A C3 and most other cars would be a different story since they don't have that torque tunnel arm.


My suspicion is that you guys are right, but I have no proof of mechanic negligence. The "crack" is apparently not visible, but the fluid is leaking around two bolts (the same ones you descibe above most likely). I'll get the old housing when I get the car back and post some pics.

Talking about over-torqued bolts reminds me of a nightmare brake job I had on my 1990 vette several years ago. The mechanic used an impact wrench on the lug nuts and I broke 5 lug sockets trying to take them back off. Finally I had to borrow an impact wrench just to get them off.

After these experiences I've decided to educate myself and start doing more of my own maintenance. At least then if something goes wrong I'll know exactly what happened and can only blame myself.

Thanks again for all the information--you guys are extremely helpful. Time to visit Helm Inc.'s web site and order the manual...

-Randall
 
Good Call on those bolts on the tailshaft housing. I forgot about what a big job it is to pry (hammer) that U channel off the back of the trans. Those are some pretty big bolts, they could be overtorqued and cause the rear bearing to bind up, overheat the seal, slam bang, Houston we have a problem.
 
Back in Action!!

The Vette is back, with NO LEAKS. The local Chevy dealer took care of it. They replaced the input shaft housing and seal. There are no visible cracks in the old housing, but they showed me one spot that looks suspect--looks like something hit or pried on it. I've attached a picture of it below. I don't know if that spot would have caused the leak or not.


It's good to be back! :beer
 
Uh Oh

If I'm looking at this picture right, my bet would be "someone" used a chisel or hard punch to install that seal.
 
Don't know

69MyWay said:
Great news!

Are you going to pursue the originall jobber on this?

Haven't decided that yet. At this point I'm just happy to have the car back, running perfectly, with no leaks.

I passed the 500 mile break-in period on the new clutch. I know I'm preaching to the choir here, but these cars are SERIOUSLY fun to drive! I've got a lot of making up to do for the last 3 years I've spent driving my 4 cyl. Camry! Life is too short to drive a Camry... :cool
 
Get that guy!

You obviously got "hammered" get a piece of your money back....nail these turkeys!
It would be helpful to get any COLOR commentary from the GM dealer who did the repairs. I am assuming this picture was a "before" pix.

BTW congrats on making it back leak free.

Mike
 
It still comes back to the fact that you started out with a good transmission
before the clutch was replaced, and it
started leaking after that.
Glad it is fixed now. Dealing with repair shops sometimes makes you feel like you are asking for way too much, being way to paticular. You just have to stick with it and demand satisfaction. ANY oil leak is not satisfactory, because it did not leak going into this.
What is the popular opinion on breaking in a clutch. The only one that I ever had a problem with was on a Z-28. I know--- that's what I get for driving a Camaro!! I think that I was way to easy on it, and the disk glazed. After that experience, if I have a new clutch I just drive normal, maybe hammer it a few times to clean off the the surface.
 

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