Need 700R4 Expert
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Need 700R4 Expert
Finished a 1991 700R4 no problems. Building a 1986 700R4 is kicking my butt. There is a "gen" change at 1987. 87 up parts don't fit the 86. Putting together the forward clutch the new stack clearance is .079. It's supposed to be min .040 max .065 (so they say). 87 up you can get different thickness apply/backing plates to adjust. Can't find any such parts for the 86. Regular Steels are .090. How do I adjust the clearance to the .040-.065 range when selective thickness parts are not available for the 86?
Same problem with the reverse input & 3-4 clutch. No "selective" thickness parts. What's the secret?
Same problem with the reverse input & 3-4 clutch. No "selective" thickness parts. What's the secret?
Racer
Joined: Dec 2003
Posts: 277
Likes: 3
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
see if this helps, there is a ton of parts.
http://www.makcotransmissionparts.com/4L60-700R4.html
http://www.makcotransmissionparts.com/4L60-700R4.html
Burning Brakes
Joined: May 2005
Posts: 1,094
Likes: 36
From: Coldville
I gave my 86 700r4 to my Manager @ work when I got my used one.
He wanted to us it in his TR6 he is building, anyway I just spoke with him and he rebuilt it with the kit over a 3 week time frame.
So it can be done by a no proffessional with the right tools.
He wanted to us it in his TR6 he is building, anyway I just spoke with him and he rebuilt it with the kit over a 3 week time frame.
So it can be done by a no proffessional with the right tools.
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
The clearance measurement was taken with a dial gage, wet clutches (fibers).
The thickness measurements were taken with a 0-1 digital mic (very accurate).
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
The GM service manual also provides no procedure to fine tune the 1986 clutch clearances. It just gives the spec for a single plate... no additional thickness's.
I need to talk to someone who really knows their way around the 700R4.
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Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
Is this strictly a stock rebuild or are you using upgraded parts?
When I rebuilt an '89 700r4 I did it with heavy duty parts and it was difficult to figure out which stock parts to leave out. My stackups were way off until I figured this out.
The heavy duty kits use more frictions and steels than stock so they have to be thinner to make the stackup come out right. That might help you.
My advice is to call the TransGo tech line (they don't do email). They can tell you where to find a trans shop near you that knows what they are doing. The experienced trans guys know all the tricks and where to look for problems. I had a cracked input drum and didn't know it because I didn't know where to look.
When I rebuilt an '89 700r4 I did it with heavy duty parts and it was difficult to figure out which stock parts to leave out. My stackups were way off until I figured this out.
The heavy duty kits use more frictions and steels than stock so they have to be thinner to make the stackup come out right. That might help you.
My advice is to call the TransGo tech line (they don't do email). They can tell you where to find a trans shop near you that knows what they are doing. The experienced trans guys know all the tricks and where to look for problems. I had a cracked input drum and didn't know it because I didn't know where to look.
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
There is only one snap ring for the Forward Clutch. This one is .124"
Thread Starter
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
The Forward Clutch in a 86 only has one snap ring (8642124), one Apply/Pressure Plate (8642163) and one Backing Plate (8642169). For 87 up there are four choices for Backing Plates to adjust the stack.
I found a part number for the .078 (thin) Regular Steel (non-wave) which GM used to initially build this unit (8642167). If I install 5 of these, I will end up with .053 clearance (+/-) which is acceptable. I just need to order more of these as I only have 2 originals. I'll order all 5 new. This means there will be two steels back-to-back like GM did originally.
The only caveat that I have is that the 8642167 is listed only for 82-84.
I was able to identify part numbers for selective fit 3/4 Clutch and Reverse Input Clutch steels so I think I'm good on those as well. I'll try to remember to repost as this progresses.
I found a part number for the .078 (thin) Regular Steel (non-wave) which GM used to initially build this unit (8642167). If I install 5 of these, I will end up with .053 clearance (+/-) which is acceptable. I just need to order more of these as I only have 2 originals. I'll order all 5 new. This means there will be two steels back-to-back like GM did originally.
The only caveat that I have is that the 8642167 is listed only for 82-84.
I was able to identify part numbers for selective fit 3/4 Clutch and Reverse Input Clutch steels so I think I'm good on those as well. I'll try to remember to repost as this progresses.