I recently installed a shift kit while changing the filter and fluid at 100k. It seemed like a reasonable thing to do. I can't say there's any downsides after doing it. Partial throttle shifts are largely the same as stock and during general driving around the shifts are just a bit harder. WOT shifts are hard and sudden and very high in the rpm band, but I rarely floor it and I don't see the behavior in this situation to be relevant. It's a big heavy, 4x4 with a heavy slant towards offroading. I've noticed the downshifts are quicker and a bit harder, but I see this as a huge benefit since the transmission would mostly refuse to downshift when I gave it gas to pass other cars.
The biggest benefits in my mind are that the transmission should last longer since there's less slip on the clutches.
First things first, you're going to look at the shift kit instructions. You're probably going to read over them say 5 or 6 times. Cause if you do anything wrong... if you misplace a little ball, drill a hole too big (or not big enough), miss changing out a spring, or put a bolt in the wrong place you stand a serious risk of destroying your transmission. There you went and spent $150 and because you couldn't follow directions you are now spending an easy $1000 or more for a new transmission.
So the PSA is, follow the directions and follow them exactly. Oh, and make sure you have an inch pound torque wrench.
I purchased the kit from
http://www.ctpowertrain.com/servlet/StoreFront. They answered the phone when I called during regular business hours and were very helpful. I picked up the kit from ebay and it was this one specifically.
http://www.ebay.com/itm/270874884435?ss ... 1497.l2649 The ebay listing includes the vette servo and a ASTM book. Both were useful.
The first thing you're going to notice is that you have a new separator plate and the directions in the shift kit are going to tell you to drill a bunch of holes in it. The good news is that most of the holes are going to need a drill bit supplied in the kit. The others are going to require a drill bit slightly bigger or smaller. Be prepared with lots of different small drill bits... think 1/16 to 1/4.
The first thing I did was identify the holes. Then I drilled them accordingly. A couple of the holes will be to size already (or bigger) and a couple more will be dependent on other internal parts. Pay attention to the instructions.
I really didn't want to spill transmission fluid everywhere. But I quickly discovered there's no clean path when you're dropping the valve body. Lay down a tarp, have a roll of blue towels ready and be prepared for a mess. Drop the pan, which requires a lil shift to the pass side and you're good to go. Then yank the filter out. After removing the pan all the bolts are 8mm and 10mm on the valve body.
With any luck your fluid doesn't look brown, burnt and shitty like mine did.
That new seperator plate I mentioned a little bit ago, you'll find it to be pretty useful cause your stock piece is probably pounded to shit. There's lots of instances where the plate is totally garbage all over the web, mine turned out to just be not good. See all those ridges around the holes? yeah, those shouldn't be there. Those are potential leaks and signs of badness.
After you drop the oil pan you're going to grab the filter, it's that big black plastic thing, and you're going to pull it out. You're going to be confronted with this...
Then you're going to release all the electrical connectors and loosen all those 10mm and 8mm bolts. While the valve body drops down you're going to release the manual valve link, this is important because you're going to need to reconnect it while you reinstall the valve body. It's just a little piece of wire, but don't forget it. When it all drops down you're going to see the following...
There's a small plate you'll need to remove that is held in with 3 bolts, but it just supports the separator plate and the only real concern is bolting it in while bolting in the valve body.
When all is said and done you'll put the valve body on the bench and see the following, take note of where these balls go and realize that there is one ball that goes in the case. It's marked in the instructions and can be held in place with Vaseline like all the other balls in the valve body.
You'll notice on disassembly that the housing for the 1-2 accumulator piston needs removed. It's three bolts. The piston inside apparently leaks and cracks commonly, especially around the pin the piston travels on. I didn't see signs of this personally, but there are a huge number of accounts online of it being a problem. I opted to move to a pinless accumulator. I had the third type housing in my truck and the only required mod was the replacement of the inner spring and the blocking of the pin along with a staking of the bore. I had to remove the old piston with a dead blow hammer, the same results could be accomplished with compressed air.
It may be of note- while I was removing the pin for the 1-2 accumulator I used a pair of channel locks. A twisting and pulling motion removed the pin. In my case I held the housing in one hand and pulled and twisted with everything I had with the other resulting in a pair a channel locks to the face. I ended up with a significant concussion and memory loss that included not knowing my address, DOB, where I was, how I got there etc, 6 internal stitches and 8 external, a week later I still have splitting headaches. Use a small punch to remove the pin or at least pull away from your face. Don't be dumb like me.
After the pin was removed I drove in the bearing per the instructions and lightly staked the housing. After that toss in the spring and piston per the instructions.
After you get that bad boy done you're gonna need to do the same in the case. The kit comes with an updated white spring to insert behind the 3-4 pinless accumulator piston. This pin came out significantly easier and then the small ball was driven in and the bore staked. Don't forget to spray it out to remove any metal flakes.
After this I moved on to the servo since the parts in there would determine what I did elsewhere. It's on the passenger side of the transmission just above the pan. It's a big circle. You're going to need to tap on that cover with a hammer a bit and then use a screwdriver to pop out the snap ring. It's challenging and takes some time, and that's after you scrape all the mud out of the groove. Try not to bend it all to hell, cause it makes it harder to get back in.
After you pop the snap ring out just use some channel locks and twist/pull it out of the case. The servo might come out in pieces, it might come out all together. There's a spring about the size of your thumb at the very end that tends to stay put. Make sure you're aware of it's existence. You can get to the servo underneath the truck or through the passenger front wheel well. Here's a pic of it's location as well as a shot of the cover, snap ring, and seal. Then one of the whole assembly.
When you get that lil bugger pulled you'll pull off a little E clip and spread the parts out. You should see something about like this spread out on your bench. This is also when you'll look for that number you need so you know what to drill a couple of the holes on the separator plate too. In my case it was 553
See that big bulky part? It's what the vette servo replaces. But before you get there you gotta grind a few notches in the retainer plate. Afterwards you can assemble the whole thing, toss the coil spacer in, add in the two springs included in the shift kit, replace the seal on the cover and it's ready to slap back in the transmission after you lube up the seals. To assemble it you're going to need some kind of press/huge c clamp/bench vise to put the servo back together. Those springs are pretty stiff. Not even moots could compress it enough and he got so frustrated he left right afterwards.
When putting it back in the transmission don't forget the gold spacer and that pesky lil spring! Also note that the 4th piston needs to have the taller side out towards the cover of the servo.
I found that while installing it I had plenty of room due to the body lift and that a few taps of a ball peen hammer got the cover to seat into the bore. I then used the ball end of the ball peen hammer and pressed it up against the center of the servo cover. I leveraged it by using the cat. Then I crammed the snap ring in with my free hand. Make sure the snap ring gets into place. If it pops out you'll be stuck on the side of the road. This process will try your patience a little bit.
Now you can go back and drill those last couple holes in the separator plate that was circled earlier.
Now is also a good time to go back and check that you still have play on the drum. You can get to it through a small hole over by where the shifter link is. Just stick a screwdriver up there and make sure the band wiggles a bit, bout 3/16" should be pretty alright. If it doesn't move you're going to need to take the servo back out and remove the wire spacer. In my case everything appeared to be hunky dory.
From here on out your moving to the valve body and swapping out springs. A small screw driver or a pick seems to work pretty good to remove the clips that retain the valves in the valve body. This is pretty straight forward and I'm not quite sure what to say about it other than follow them directions. I took lots of pics along the way so I'm going to toss em on up. I'll mention some of the unusual stuff. You can turn the valve body sideways or use a screwdriver or whatever to get the valves out. I used a mixture of both.
This first valve here needs to be verified to be the smaller .441 valve, it should be on our trucks, but you never know. Might maybe wanna check.
and the replacement... make sure you use the lil screw and make sure this valve moves freely, apparently it's important.
Just swapping out a spring here...
on to the other side where most of the work occurs...
you'll notice this clip is four channels back, make sure it goes back there.
Next valve down, you'll want to note the housing number so you can pick the correct spring from the chart. Also note that it's held in with a little roll pin that needs to be pulled up, it can't be pushed through.
Stock
New spring selected from the chart due to the markings on the housing. When you install the spring and valve make sure the spring goes in straight. I tilted the valve body per the instructions and then checked it when in place.
Now on to the forward accumulator. I swapped it to a pinless setup and it requires two balls to plug passages. You'll notice there's a roll pin here as well. It can be driven through the valve body. Otherwise it's just replacing springs.
After this you're pretty much done, except for the pressure booster. It's located at the front of the transmission by the gear selector. Quite frankly I didn't have enough hands to document this well. But you need to remove the snap ring pictured, pull out the valve, swap out the two springs with the one included in the kit and then push it all back up in the transmission, and then hold it in place while you cram the snap ring back in. It kinda sucks.
After that slather the valve body with vaseline to hold the check balls in place, make sure you do the same for the check ball in the case by the 1-2/3-4 accumulator and bolt it all together. After you get a few bolts in make sure you hook up the shifter link, and make sure you tighten up the retainer support plate for the separator plate. Make absolutely sure the bolts go where they need to go. Follow the chart in the instructions exactly. I tightened the bolts up in 3 passes in a circular motion... 45 in lbs, 65 in lbs, 96 in lbs. The oil pan bolts were tightened to 96 in lbs. Don't forget to pour some new fluid in, let it idle and get up to temp to melt out some of the vaseline and then enjoy your drive.