automatic transmission...86 same as 88?
Thread Starter
Instructor
Joined: Jun 2008
Posts: 166
Likes: 0
From: San Antonio Texas
automatic transmission...86 same as 88?
Just wanted to make sure that the 86 and 88 tranny is interchangable without any problems. I'm pretty sure that they are both 700r4, right? Just didn't know if there are extra bits and pieces here or there that I need to be aware of if I swap an 86 into my 88. Also, what is a fair used price to pay?
Instructor
Joined: Sep 2008
Posts: 136
Likes: 0
From: DFW TX
They are both 700r4. A 700 is a 700. They didn't change at all.
For a used one I wouldn't pay more than $100 unless it is freshly rebuilt by a reputable company or an ASE certified tech with a cert in trans rebuild. The 700 is by far the most complicated Chevy trans out there.
Good luck. Also if it doesn't come with a converter buy a new one and flush the trans before you put the new converter on.
For a used one I wouldn't pay more than $100 unless it is freshly rebuilt by a reputable company or an ASE certified tech with a cert in trans rebuild. The 700 is by far the most complicated Chevy trans out there.
Good luck. Also if it doesn't come with a converter buy a new one and flush the trans before you put the new converter on.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Instructor
Joined: Sep 2008
Posts: 136
Likes: 0
From: DFW TX
Interesting. If this is correct then there are a few trans shops that might like to know this.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
And a genuine Vette trans has features (servos / valvebody /governor etc) different to regular T700; mainly to do with shift points.
A reg trans can have the tailshaft housing swapped and be built up to same or exceed Vette specs but as they come out of the car they are different
A reg trans can have the tailshaft housing swapped and be built up to same or exceed Vette specs but as they come out of the car they are different
Thread Starter
Instructor
Joined: Jun 2008
Posts: 166
Likes: 0
From: San Antonio Texas
Hmm...well, what would I expect to pay for a stock rebuild? Nothing fancy but nothing cheap. Just to rebuild it the way it came. This guy hasn't gotten back to me with a price on the one he's parting out of his 86. I was figuring that a rebuild would run about $1000. Am I about right?
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
I had my trans rebuilt last year for $1,200 but that was a heavy duty rebuild, a standard rebuild would be a little less. That price was with me pulling the trans and doing the install.For a shop to do pull and install add about $700 to $800 more... WW
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Michael S. Palmer
Race Director
Joined: Jun 1999
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From: Merritt Ils Fl
Quote from the ATSG 700R4 update manual:
" The 1987 and 1988 THM 700R4 transmission was produced with many major engineering design changes. These changes affected nearly every part used in the 700R4. ----------
1. Accumulator auxiliary valve body added.
2. Neutral to reverse garage shift fixed.
3. Apply package, 3-4 clutch.
4. Low and reverse roller clutch.
5. Overrun clutch lubrication.
6. Heavy duty input sprag assembly.
7. Temperature switch added.
8. Selective backing plates.
9. Forward clutch backing plate revised.
10. Revised 1-2 valve train.
11. Speed sensor added for anti skid braking.
12 Ten vane oil pump.
13. Accumulator piston and seal change.
14. "S" and "T" trucks 215 ft.lbs converter damper.
These were major changes in the trans.
" The 1987 and 1988 THM 700R4 transmission was produced with many major engineering design changes. These changes affected nearly every part used in the 700R4. ----------
1. Accumulator auxiliary valve body added.
2. Neutral to reverse garage shift fixed.
3. Apply package, 3-4 clutch.
4. Low and reverse roller clutch.
5. Overrun clutch lubrication.
6. Heavy duty input sprag assembly.
7. Temperature switch added.
8. Selective backing plates.
9. Forward clutch backing plate revised.
10. Revised 1-2 valve train.
11. Speed sensor added for anti skid braking.
12 Ten vane oil pump.
13. Accumulator piston and seal change.
14. "S" and "T" trucks 215 ft.lbs converter damper.
These were major changes in the trans.
Drifting
Joined: Mar 2000
Posts: 1,630
Likes: 1
From: Woodstock GA
Not all of the changes applied to the Vette the real difference if the aux. valve body to improve grage shift feel it's away that was used to reduce apply pressure during garage shift with little or no throttle clutches would apply with much lower pressure but if you did give it a little more throttle pressure would come up fast. This came out in the 87 modle year some of the real early 87 still had the older 700R4. Now you do have to keep an eye out for some of those early 700R4 with the aux. valve body. The cover of the accumulator had a round hole and it would let the piston pin walk out which would burn the trans up that latter ones whent with an oval hole the pin could not fit through. You should have no problem using a good 88 I have been using 91s in the early L98s(have to change some of the pressure switches) when GM stopped offering them.
David Fulcher
David Fulcher
Race Director
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From: Partying with the Cowboys cheerleaders in Mt. Olive, New Jersey
Costed me about that amount to have it rebuilt. I just dropped the car off, and picked it up a few days later. I trust the trans shop the next town over, they do quality work. However, in the event my trans craps out again, I'm going to have it rebuilt by a CF member, PeteK, who's located in PA. The dude does excellent work, just do a search on him.
Drifting
Joined: Jul 2006
Posts: 1,483
Likes: 3
From: Newark, New Jersey
not to hijack this thread, but are there any identifying marks on the trans that tells what year it is? The previous owner I bought my 86 from told me he had installed a trans from a 88. I'm curious as if i do in fact have a different trans or the stock trans
I found the info i was looking for.
http://www.technicalvideos.com/what_year_700R4.phtml
I found the info i was looking for.
http://www.technicalvideos.com/what_year_700R4.phtml
Last edited by jon0108; Jan 10, 2009 at 08:37 AM.
Race Director
Joined: Feb 2004
Posts: 12,517
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Just wanted to make sure that the 86 and 88 tranny is interchangable without any problems. I'm pretty sure that they are both 700r4, right? Just didn't know if there are extra bits and pieces here or there that I need to be aware of if I swap an 86 into my 88. Also, what is a fair used price to pay?
If it is not a vette trans, it will require modification to fit. Primarily cutting down the output shaft 3/4 inch.