91z28tpi355

iTrader: (2)

Hey guys, I want to start off by thanking everyone on this site for helping me up to this point. I am fairly new to the site, but I have got an answer to all of my questions so far. I just rebuilt my 700r4 with a TCI pro-super kit, and an ATSG manual, and everything went well through the rebuild. After everything was complete, I took the car for a road test, and after some T.V. cable adjustments, everything worked perfectly with the forward gears, but I have absolutely NO REVERSE! I plan on dropping the pan in the next couple of days, and checking the valve body out, but I am almost positive all of the clips went back in fine. The only other thing that I can think of that may be wrong is the reverse input drum. When I dissasembled the tranny, the spring assembly for the reverse input clutches was absolutely destroyed, so I went to my local tranny parts supplier, and purchased a new drum. Everything looked the same, so I just installed my TCI clutches, and steels, and put everything back together with the new drum. After I put the entire thing back together, I noticed that the box for the drum said that it was a 93', and my ATSG manual says that the 93' has to be used with a 93' pump, and 93' check ball locations in the valve body. I am hoping this is not the case, but any expert advice would be greatly appreciated. Thanks in advance for any advice!

Floor guy

Did you air check the reverse input drum?

91z28tpi355

iTrader: (2)

Yes, everything air checked fine before re-assembly.

jr. gearhead

check the locations of the check *****...that is most likely your trouble. also look at the code on the pass side stamped right above the pan. the first digit is the year of the trans. might be from a different vehicle. 93was also the year the 700 went electronic (called the 4L60E) and has some changes in the internals as well. most of the hard parts are the same though. call the guys at transmission exchange and see if they can shed some light on it. 800-776-1191 Transmission Exchange Co.

91z28tpi355

iTrader: (2)

Well, I dropped the pan today, and nothing seemed to be out of place. all of the valves are still in their places, and the pump valve was not laying in the pan. Before I dropped the pan, I took it around the block, and noticed that it seems to be taking off in second instead of first now. First was working fine this weekend, but it does'nt seem to be now. As far as the check ball locations, they are right according to the TCI kit instructions, but the ATSG book shows 87-92 how I have them, but 93 having one more, and the other two just how I have them. My tranny is a 92, but the drum that I put in it is a 93. Should I try adding the extra checkball that it is showing for 93, or have I screwed something else up? I was really hoping to see a valve laying in my pan when I dropped it.

Shagwell

they did still make 4L60(non e/electronic) in 93, just in few models.
Does the TCI manual show the check ***** in the same place the ATSG does? Are you sure the servo pin height is correct and the band is seated properly?

jr. gearhead

the only other possibility is the low-reverse roller clutch (way in the back of the trans) the clutch free-wheels in all forward gears and is supposed to hold to make reverse work. problem is to check it you have to pull the tranny and take almost every part out. the center of the clutch (which is retained to the case by a large snap ring) should only rotate clockwise. my guess is that it is free-wheeling both ways.

91z28tpi355

iTrader: (2)

Can I check to make sure the band is seated properly with just the pan off? I made sure the roller clutch locked correctly before installing it, so I know for sure that is'nt the problem. As far as the checkballs, The TCI kit has them in the same place as the ATSG manual shows, but it only has me using 2 instead of 6 in the case.

Shagwell

hummm, sounds about right, I was thinking superior called for 3, but I'd have to look to refresh my memory. - jr. gearhead was right on on his theory, but if you checked it and you're sure it's ok, then that's not it. - Checking the band anchor pin would be hard w/o having the pump out, or w/o puling the vb and pulling the ancchor pin, which would in turn make it hard to get the pin back in and know that it's seated in the band. You can pull the servos and make sure the servo pin isn't sliding in over top the seat for it though.

jr. gearhead

the band is holding in 2nd and 4th, loose in all other gears. the reverse drum (what the band rides on) actually turns counterclockwise (from the pump end) in 1st and 3rd, which is backwards from all the other parts. the drum turns clockwise in reverse gear due to the clutch inside grabbing the input drum inside it. i'll have to dig in my library to see if you do infact need all the check *****, but i put them in mine. they all do something different, but i doubt you can hurt anything by putting them in.

jr. gearhead

after re-reading everything said here, i would suggest putting in the remaining checkballs and see what happens. some affect the accumulators and such for the other gears also. (like starting out in 2nd)

jr. gearhead

made a pdf that should help

Shagwell

just checked - you need to run the 93 check ball locations. - my bet is that your new reverse drum is the 93 style w/o the internal check ball orifice. The newer drum requires the '93 check ball locations - You should just need to add the one special one for the 93 model year. The others can still be omitted for the "shift kit".
- aftermarket kits that shift improve reccommend leaving several check ***** out.

91z28tpi355

iTrader: (2)

Well, I dropped the valve body, and installed the third check ball, in the location for the 93' model, and drilled out the orifice hole for it on the spacer plate. Still no reverse, but all forward gears work great. Unfortunately, I think I have another problem most likely with the air fuel ratio, I'm thinking. I floored it on the highway to see how the kickdown was working, and it dropped into second just like it should, and after it shifted into third, I let out of the gas completely, and it backfired EXTREMELY loud out the exhauts. Anyways, I'm still stumped, but forward gears are right on the money.
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I forgot to mention, I'm thinking of going to the junkyard and pulling a 93' valve body to see the sizes of the checkballs in it. Is ther a chance that the one for the third checkball location is a different size? That's my only other guess right now. I'm getting frustrated right now. There is a pull-it-yourself junkyard right down the street from me that has a 93' Caprice. That should be a 700r4 right?

osp97b4c

Make sure you have the correct case and valve body gaskets, there are two different sets. One set is for '93 and the other is for '92-older if I remember correctly. I had this problem on my first 700R4 rebuild.

Sean

Shagwell

another thought(although i'm not sure if it would cause the issue or not) are you sure the reverse boost valve is in correctly?

87zjeff

iTrader: (4)

i use a '93 and up reverse input drum in my '86 model non-aux tranny and don't modify checkball locations at all. i have a perfect reverse. the low roller clutch is also engaged in 1st(D) and LO1.

i think shagwellmight be on to something with the reverse boost assembly since i believe it affects 2nd as well

Shagwell

- if you look at the design of it I just figured it'd be easy to put it in upside down by mistake.....not sure it would cause the problem though I'm sure it'd screw with something if not correct.

91z28tpi355

iTrader: (2)

I will try to check the boost valve this weekend. If that doesn't work, I may drop the tranny again, and convert it to a T-5. I'll let you guys know what I find out. I really apreciate all of the help you have been giving me.

87irocpaxton

I'm very interested to see what u find. I have a 87 iroc that I rebuilt a 4 bolt main 350 , put a Paxton on it.......I rebuilt the 700r4 put a b&m shift kit in it ----well I took it off the blocks today n I have foward but no reverse seems like it goes into reverse but barely moves .........I'll keep u posted.......thinkin bout going stick ..........stupid automatic

tealman92

Check the date of the last post before yours. 2006

87irocpaxton

Lol