Been learning about transmissions and putting in new servo and shift kit in my 700r4, never have done any work on them yet, and I came across an older post below where someone mentioned IROC's came with the Corvette servo already. Is that statement correct? I have an '89 5.7

https://www.thirdgen.org/forums/tran...tte-servo.html

 

Unless the car is 100% original, you won't know what is in there until you tear into it. The corvette servo trick has been common knowledge for a long time.

 

 

Let me put it this way... In all my years on this forum, I've failed to notice a bunch of threads from members saying they went to install a Corvette servo, only to find out they already had one in the trans.

At this point, it's really irrelevant what was installed at the factory. All the way back when GM Performance Parts came up with the ZZ engine swap package for carbed thirdgens, they published the part numbers and the recommendation to upgrade the boost valve and servo. Back when the internet was still in it's infancy, there were text documents with ASCII text layouts explaining the how and why of the Corvette servo and boost valve. Somewhere there's probably a drawing on the wall of some cave in deepest darkest Africa of some stick people installing a Corvette servo next to a hunting party killing a mammoth.

Considering how long the practice has been around, the parts could have been changed at a dealer to appease an unhappy buyer, or as part of a rebuild, or in a remanned transmission, or the transmission from an Astrovan that someone could have stuffed in there.

It's just like everything else, even if it's SUPPOSED to be there, unless you verify it, you won't know. Schrödinger's Servo.