FRUSTRATION IS TAKING ITS TOLL!!!!!!
Issues:
No reverse (cannot feel it engage/no movement at all)
Free revs in D and OD while driving

Vehicle is a 1996 S-Blazer 4l60e 4wd 130k
This is just after my rebuild using a TCI kit, vette servo, shift kit, reman converter, and a new gear selector switch. Originally it free rev'd it 3rd/4th (worn 3/4 clutches) Nothing else appeared damaged or broken, sun shell was fine

99% sure everything was within spec (clearences etc.)
The reverse issue has me puzzled more than anything, that I have no movement at all (read up that reverse uses the most pressure to engage)
The 3/4 clutches with the TCI kit, I used 8 clutches and 8 steels compared to stock 6/6 to get the correct stack height.

Am I looking towards a pressure issue within the valve body? Pump issue? Boost valve not seated or bound? Bad EPC?
Are these 2 problems related or seperate?

Thanks ahead of time this site has been great so far!!!

 

IMO, never reuse a standard sun shell. 'The Beast' sunshell was only $38 when I bought mine and it is noticeably beefier.

Have you checked over the seals on your new 2-4 servo (vette servo)? You might have more than one issue which makes it VERY difficult to diagnose over the internet.

Hope this wasn't your first attempt at rebuilding a modern automatic...

 

Thanks for the advice so far! I've tore into a few autos before but never one that has so many PCM related problems.

Starting with the basics:
Checking linkage
Verifying part #s on gear selector switch (correct year)
Putting air to the valve body to check for excess fluid leaking out a bolt hole etc.
Checking valves in pump
Pulling valve body
Then if that does not resolve anything the transmission will be coming back out

 

Ok, I don't even have a blazer anymore, But have a few thousand 700r4/4l60e rebuilds under my belt,(23 yrs as occupation) stumbled on this forum and wanted to try to help. First things first...Does the transmission have "engine braking" in manual 1st/low gear position ...like if you pull it into first from 20 MPH. Also, To what extent did you disassemble the trans? Did you remove all the pistons and replace all the seals? Did you change the 2 white teflon rings on the back of the pump? Any "hard part" changes or just the kit and clutches?

When you say free revs in d and od do you mean when it tries to shift to 3rd and 4th in these selector positions...or do you mean it won't move from a stop unless you put it in 2 or 1?

If you don't have reverse don't worry about anything electrical because there is absolutely nothing electrical required for reverse and the EPC will almost always fail "high pressure" Todd