Hey guys,

I pulled my engine a few days ago, and the 700R4 is just dangling there taunting me to play with it. I'm building up a 355 and I know the life of the 700R4 Is going to be short, and I want to install a GM 3-4 WOT upshift kit but I've never done anything to a auto other than change fluid/filters. How do I get to/ get out the valve body, access the 3-4 valve and change it?
Are there any tutorials?
Anythings i need to be aware of? like $90 worth of gaskets or something?

Is the vette servo an easy install as well?

How big of a chore am i getting into here?
thanks!

 

how's the present condition of your trans, i.e.mileage, fluid condition, etc? If it's not in bad condition (50k miles or so), you'd be ok playing with it. th 3-4 shift valve intall is pretty simple. you will most likely need a pan gasket, you will need upper and lower seperator plate gaskets (totaling $10-15) and a good reference source like shop manual fom the dealer(sometimes they will print out things like check ball location pages and torque specs, etc). You can also find useful material at the local library. the 2-4 servo isn't too hard, the hardest part is getting the servo cover off. after that it's pretty easy. it's is easier(easiest) to change this with the tans out of the vehicle. you will need to make sure that you get new teflon sealing rings and rubber orings with the servo. you will need a small screwdriver or a pick to remove/install the 3rd accumulator spring/cover assembly, along with a little elbow grease. you find out what i'm talking about. :-).
If you want a decent source of info, you can contact your local tansmission parts supplier and purchase a copy of the ATSG 700R4 manual. Or if your interested I can send you the info via email. buddrow1@aol.com

lemme know.

 

Wow!!! That was more than helpfull!!

The tranny has probably around that many, there's 110k on the vehicle, and the tranny was rebuilt before I got it so possibly less, are there any special tools or precautions? anything going to come flying out at me when i crack the case? etc?


Thanks a ton!

 

Some check ***** will come out when you take the VB off and the sep. plate off. Make sure you don't loose any. A good shop manual will show where they go.

 

Do yourself a favor and install the Trans-Go Performance Shift kit, both boost valves, & a Corvette servo. If you want the 3-4 at WOT & do not want a 4-3 kickdown at freeway speeds there is a simple way of doing this yourself, modifying the TV plunger sleeve with two small allen plugs and a little grinding with a Dremel (about .34 cents for the allen plugs). This will do a lot towards giving you the performance you want, along with durability. Let me know if I can be of any help.

 

So without this alan plug modification I risk the car dropping into 3rd at highway speeds? I have 3.73's and I absolutely can NOT risk an unexpected downshift into 3rd, I'd ruin everything.

 

If you do not want the 4-3 downshift "at all" at high speeds, then I would do the modifications (block the holes) to the part throttle passages in the TV plunger bushing.

 

Awesome!!!!

That sounds EXACTLY like what I want, basically a manual overdrive, Do you have any pics or scans ofthis modification so I know what im looking at? At least maybe a photoshopped Red arrow pointing at what im blocking

Thanks!