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· Registered
71 Posts
Discussion Starter · #1 · (Edited)
I installed a new corvette servo on Saturday and can hardly believe the difference. From typical gutless van to a powerhouse on take off, amazing! This has been one of my top five modifications, honestly so easy, took 20 minutes, and such a drastic difference.

After pulling the C ring clip out, then cutting the o-ring off the old servo, then with water pump pliers I rocked it back and forth and pop it came out with probably a quarter cup of trans fluid. Putting the new one in was fairly simple, oiled all the o-rings with my spilage, used the pliers to again rock it back and forth, it soon popped into place and I installed the c ring.

Here are pictures of what I bought, I know I could have rebuilt what I had, just decided to get brand new, maybe the results would have been the same, unfortunately I didn't take any pictures of the actual install but I will remove the aluminum heat shield and get a shot of it installed. Thanks mmusicman and others who wrote about their installs and questions.


· Registered
2000 Lifted 4x4 Astro 92 V8-350 Shorty
6,370 Posts
Glad to see it worked out so nicely for you. This should be considered a "must do" for anyone looking for easy performance upgrades... especially since it's fairly easy and inexpensive, with such nice results.

Labor is not hard either, since servo is located on side of transmission.

At the time.. I think I paid about $12 for mine on Ebay, the incomplete performance set you build with "some" parts from original. Same result

Good job!

· Registered
13 Posts
One important thing U should check after install any servo parts - the clearance of 2-4 band
If it too loose - U will achieve bumpy shift
If it too tight - U will glaze 2-4 band and it will loose its holding capacity significantly
Oem specs allows quite big gap
After reading a ton of forums and articles I prefer adjust it to 1.5-2mm (0.06-0.08)
For those who don't want firm shift but only slight improvement of holding capacity -there is 2-4 servo from 4L70e (read about it from Sonnax article )
Not so big as vette servo but much bigger than oem v6 2-4 servo
My setup is wide 2-4 band + sonnax superhold servo (I was noob into tranny rebuild and bought most expensive parts in hope that they are the best)
After I spent a lot of trying to drill exact orifice hole to 2nd shift I achieve some comfort at light to medium throttle -but I avoid to use WOT ) This fking beast trying kick my *** when shifts 1-2
Next step is to enrich torque cut off % at shifting into PCM shift map
OEM calibrations only cut power at 2-3 shifts
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