Over the past few weeks I have read two treads dealing with the changes in the TH-700-R4. I understand that the auxillary valve body modification was not used in early 87, but was switched about the time my GTA was manufactured. How can I tell for sure without removing the pan? Any help is appreciated.

 

Even if it is the later one, it is not the preferable one if you are planning on a street/strip or one for road racing. The 1987 w/aux valve body still used the early main valve body. I prefer using the 1988-1992 transmissions for performance build ups. The 1987's are good for heavy duty build ups, but not much more. When using the Trans-Go Performance Shift kit in the 1987's, we have had peculiar things happen, and other shops have told me the same thing, not in all cases but about half of the time.
Hope This Helps!!!

 

Pro Built, thanks for the info. I was wondering if you could educate me some more? Could you explain the differnces in the old main valve body, 87 tranny, and the newer main valve body, 88. Thanks for your help.

 

You should have the Auxillary Valvbody. The Auxillary Valvebody was added on October 6, 1986. Yours was built 4 months prior to the '88 Production Run.

In 1988, the new valvbody and spacer plate was installed, and CANNOT be put on prior transmissions. It included changes for 1-2/3-4 shift valvetrains. The did other non-valvbody changes in '88, but I won't bore you.

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ASE Master Tech + L1
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'87 Trans Am
S/D TPI retrofit including functional PassKey,
22# injectors,
Whatever chip I feel like burning,
JET AFPR, Ported Plenum,
TB Coolant Bypass, Custom Cold Air,
SSM SFC, KYB Shocks, Boxed LCAs, Wonder Bar,
8mm Accel wires,
Flowmaster Exhaust,
16" GTA rims,
Corvette Servo,
3.73 Posi
4wheel Disc Brakes

'97 Bonneville SSE

 

GM Tech, thanks for the info. It sounds like my 87 tranny is a transitional unit, some, but not all the new stuff.

Would you recommend synthetic fluid? If so what brand? Thanks