I recently installed a Corvette Servo in my transmission, and thought I'd take the time to make a walkthrough, since I know how it can be nerve-wracking digging into your trans. Before you begin, I just want to reassure you, its not very hard to do!! It took me about an hour, and thats with taking my time to clean my hands so I could take pictures.

Now, your probably thinking "what the hell would I need this for?!" Well, basically, all this does is gives you a firmer 1st-2nd, 2nd-3rd gear shift, and gives you 50% better holding power in second gear. It uses a bigger piston to apply against the band, which in turn holds the drum alot better. Its not going to chirp the tires every gear like a shift kit would, but it will give you an improvement in shift quality, which is good for towing and such.


For starters, your gonna need your corvette servo, I got mine off of ebay from a company called CT Powertrain, it costed a whopping $14 bucks.



http://www.ebay.com/itm/700-700R4-4L...e1e231&vxp=mtr

For tools, all you need is some picks, a couple flathead screwdrivers, channel locks, a big c-clamp, some brake clean, and a quart of FRESH trans fluid.

BE SURE TO CLEAN ALL PARTS WITH BREAK CLEAN AND A LINT FREE TOWEL!!!

The valvebody in the trans has very tight tolerances, and even a small piece of lint can screw up its operation, so everything has to be PERFECTLY CLEAN!! I used paper towels to wipe everything down, and I suggest you do the same!!

First, jack up the passenger side of the vehicle, get under, and this is what your looking for.



Now get your big screwdriver, and pry that cover in. I went against the torsion bar on my blazer, and that worked great! Now look closely, see the notch? Theres a big c clip you need to pull. I got that out with a smaller flathead. Now you can pull the cover off! Chances are, its not just gonna pop out, so use your channel locks on that little circle part, and rotate it back and forth until it walks out.



After you get that off, this is what your gonna be looking at. This is the 4th gear apply piston.



Now pull it out! It just slides right off



What your looking at now



Out of the trans!



Now pull the rest of the servo



Then this spring. Don't loose this!!



Now that you have the assembly out, its time to swap some parts. First pull this e-clip, careful because it has a tendency to fly across the garage and go missing. Save yourself the headache and cover it with your hand while you pull it. This is where your 90 degree pick tool comes in handy!!



Now you should have these parts lying out on your workbench



Next, pull the piston rod out. This is what physically touches the band



Compress the spring with your c-clamp



Pull the snap ring



Now pull this cover off, and the big spring. You'll be transfering these to the new servo





Comparing old parts (left) to new (right)



The new servo, install your new teflon rings into the grooves







Slide the piston back in



Install the spring



Washer



And finally the e-clip



Now for re-installation! First install the spring...



Then the second gear servo assembly



Then this thing (don't know the name of it) MAKE SURE the notches on it point OUTWARDS!!



Then the 4th gear apply piston. Make sure you install it the right way, or you'll have to pop the cover off and turn it around to get overdrive back



Then the servo cover!! Be sure to throw your new o-ring on, and lube everything with trans fluid!



Now, all you have to do is pop the servo cover on, throw on the snap ring then take it for a test drive. If it doesn't leak on the first startup, then you should be fine! Now take it for a test drive and enjoy your nice crisp shifts!!

 

Good walk thru! If you had to do it again would you go straight to the corvette or sonething in between, a little less aggressive? Also do you know how to fool the electronic pressure regulator with a resistor?

 

Very interesting, nice write up!

 

Thanks!! I think I would recommend using the corvette servo, because its a tried and true GM designed part, and I don't feel its very aggressive to be honest. I'd reccomend it to someone who would like to improve the mushy shift from the factory, without going overboard with a shift kit. And no, I've never heard of doing that to be honest. If you'd like to shed some light on that feel free!!

Thanks!! I feel like it was well worth the effort to take the time so others can feel confident doing this mod!

 

The thread is kind of old but I think it is THE $4.00 TRANS MOD or something like that. It also speaks about too much pressure. My trans parts man suggested that the vette servo is too much and the stock one is too cush. I think he said there were 4 stock sizes

 

I read last week that you were waiting on your vette servo... thanks so much for posting this walk through, if I don't use it this weekend... well, that means I found out it's not my servo- but I'm sure it will come in handy for someone!

 

Did this on my servo, not to aggressive at all. Tighter shift, less slippage, less wear. Worth 14.00 and an hours work

 

I'll have to look that up. I've never seen any different sizes, we did one on my buddies 02 Z71 Silverado, and it was the same part as mine.

Glad I could help!! Hope it goes well for you, I'm really enjoying mine so far. I've put about 250 miles on it so far and haven't had an issue yet!

That's what I said!! I can almost chirp second when I get on it! The back end just squats when it shifts under WOT now..

 

This is looking like an easy project. It affects 1-2 shift only or all shifts?

 

I believe it effects all but I notice it most on 1-2