700R4 Tailshaft
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
Likes: 0
From: Byron Center MI
700R4 Tailshaft
I am replacing the tailshaft seal because of a leak and it seems there is some play in the output shaft. It does not seem normal.
Is there a bushing in the tailshaft to hold the output shaft firmly?
I have a GM 700R4 technician's guide that shows a bushing in the tailshaft but does not illustrate the Corvette tailshaft housing.
Where can I get this bushing?
Thanks for your help. Tim
Is there a bushing in the tailshaft to hold the output shaft firmly?
I have a GM 700R4 technician's guide that shows a bushing in the tailshaft but does not illustrate the Corvette tailshaft housing.
Where can I get this bushing?
Thanks for your help. Tim
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
The bushing was common to all 700's 4l60e's and turbo 350's. I have 20 of them at home, but will not be home for over a week. Any trans shop should be able to sell you one for $5. Dealer would be a second option.
If you have a choice, buy the teflon bushing. They are $10 or so.
If you have a choice, buy the teflon bushing. They are $10 or so.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
Likes: 0
From: Byron Center MI
Pete, you never fail to amaze me with your quick responses.
Is there anything else I should be looking for? I'm thinking the play in the output shaft would be causing the leak.
Is there anything else I should be looking for? I'm thinking the play in the output shaft would be causing the leak.
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
1)Bushing surface on yoke for wear or damage
2) Oil drain back hole in trans case should be checked for sludge blockage. This is easily seen with the tailshaft off.
3) Change 0-ring for speedo sensor while you are there. Pennies, and easy to change.
4) Inspect speedo gears, and change if visibly worn. Again, cheap.
5) Wiggle output shaft up and down once tailhousing is removed. If it goes up and down more that 1/4 inch, case busing inside if worn, and will need changing.
*Hope #5 is ok, because complete disassembly is required for replacement.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
Likes: 0
From: Byron Center MI
It likely is, but check the following while it is apart:
1)Bushing surface on yoke for wear or damage
2) Oil drain back hole in trans case should be checked for sludge blockage. This is easily seen with the tailshaft off.
3) Change 0-ring for speedo sensor while you are there. Pennies, and easy to change.
4) Inspect speedo gears, and change if visibly worn. Again, cheap.
5) Wiggle output shaft up and down once tailhousing is removed. If it goes up and down more that 1/4 inch, case busing inside if worn, and will need changing.
*Hope #5 is ok, because complete disassembly is required for replacement.
1)Bushing surface on yoke for wear or damage
2) Oil drain back hole in trans case should be checked for sludge blockage. This is easily seen with the tailshaft off.
3) Change 0-ring for speedo sensor while you are there. Pennies, and easy to change.
4) Inspect speedo gears, and change if visibly worn. Again, cheap.
5) Wiggle output shaft up and down once tailhousing is removed. If it goes up and down more that 1/4 inch, case busing inside if worn, and will need changing.
*Hope #5 is ok, because complete disassembly is required for replacement.
I will check the other items while I'm there.
I hope I don't have an issue with #5. I don't think so because there really isn't that much play at the end of the tailshaft housing. Just enough to make me want to replace the bushing in the tailshaft housing.
Thanks again Pete.
Melting Slicks
Joined: Mar 2008
Posts: 2,453
Likes: 347
From: SC
Pete K, while you are here maybe you could help me with a trans pan leak. Had gasket replaced,stll a leak. Replaced pan and gasket and still a leak. Any suggestions as to what could be the problem.
Thanks
Thanks
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Install cork pan gasket with no sealer, only a thin film of vaseline on it.
Torque bolts to 100 inch pounds 3 times, then a week or 2 later, retorque to 100 inch pounds.
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Burning Brakes
Joined: Feb 2002
Posts: 804
Likes: 5
From: Fresno CA
It's a Moroso fabricated aluminum pan and when I first put it on it leaked like crazy so I pulled it off and checked it on a surface plate only to find out it was warped from the factory. I took it to a machine shop and had it surfaced and trued, put it back on using one of the thin fiber style gaskets (as per Moroso) torqued it to 100 inch pounds and it was much better for a couple hundred miles but then I recently pulled the trans to fix an oil leak behind the flexplate and never pulled the pan or removed the bolts, put the trans back in and once again it's leaking really bad. It appears that the ATF is seeping either thru the gasket and wicking out or leaking out on either side of the gasket, I really can't tell. I went back and checked torque on the bolts and they were all tight at 100 inch pounds so I'm wondering if I should just go back to a stock pan or try maybe a cork gasket?
Last edited by eguyett1985; Apr 2, 2009 at 02:43 AM.
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
I'm having similar problems with my trans pan too It's a Moroso fabricated aluminum pan and when I first put it on it leaked like crazy so I pulled it off and checked it on a surface plate only to find out it was warped from the factory. I took it to a machine shop and had it surfaced and trued, put it back on using one of the thin fiber style gaskets (as per Moroso) torqued it to 100 inch pounds and it was much better for a couple hundred miles but then I recently pulled the trans to fix an oil leak behind the flexplate and never pulled the pan or removed the bolts, put the trans back in and once again it's leaking really bad. It appears that the ATF is seeping either thru the gasket and wicking out or leaking out on either side of the gasket, I really can't tell. I went back and checked torque on the bolts and they were all tight at 100 inch pounds so I'm wondering if I should just go back to a stock pan or try maybe a cork gasket?
It's a Moroso fabricated aluminum pan and when I first put it on it leaked like crazy so I pulled it off and checked it on a surface plate only to find out it was warped from the factory. I took it to a machine shop and had it surfaced and trued, put it back on using one of the thin fiber style gaskets (as per Moroso) torqued it to 100 inch pounds and it was much better for a couple hundred miles but then I recently pulled the trans to fix an oil leak behind the flexplate and never pulled the pan or removed the bolts, put the trans back in and once again it's leaking really bad. It appears that the ATF is seeping either thru the gasket and wicking out or leaking out on either side of the gasket, I really can't tell. I went back and checked torque on the bolts and they were all tight at 100 inch pounds so I'm wondering if I should just go back to a stock pan or try maybe a cork gasket?It swells a wee bit.
People complain about cork all the time, but I have never had a problem, if the pan was flat.
