Hey i put a post up a while ago about my 700 shifting weird after me and my dad tried to get it out of the snow. welll after some research ive noticed that every says absolutely do not put rtv on tranny pan. about six months ago my i let my friend(whom is a mechanic and a damn good one at that) do the tranny gasket cause it was cooked. well we were tight on cash and i had no clue this could cause problems. it fixed the leak but now my car shifts horrible it hits 4000rpm before shifting to second and shifts odd in all other gears. could this be my problem. can it be fixed. if so i will change filter and gasket this weekend. also could it be modulator valve? and how can i check. im being told my clutch packs arent whooped so whats the deal. thanks guys
ps- could it be throttle valve cable? is that on an 88 700r? thanks


Brendan 88 camaro 305v8 tbi

Nothing wrong with rtv, but too much rtv will seap in there and cause problems.. Drop the pan and check it out..

If the TV Cable is broke or came disconected from either the trans or the throttle body it might cause that also. 700R4 doesn't have modulator valve like the TH350s and TH400s. TV cable affects when the trans is supposed to shift. There is also an adjustment on the TV Cable where it hooks into the bracket near the throttle body. Its all plastic junk so it might be stripped out or it might need to be re-adjusted. Hope this helps.

The 700R4 has a vent hole for the 4th gear servo that is on the pan rail. RTV will plug it up and prevent it from shifting. I'd avoid using RTV except in a few very specific applications. It's not generally good for gasket sealing.

The TV cable adjustment is very critical. Ideally it is set up with a pressure guage attached to the tranny. As many others have learned, setting it incorrectly will lead to a transmission failure.

ok so if the rtv did plug that seal can i fix it? and i did readjust the tv cable i did it like the book, slid the cable back while pressing button and then gave it wot and it clicked up into its proper adjustment. it does shift a bit better but not like before. still seems off. should i replace the cable. whats the ideal shift speeds to rpm. thanks a lot for the answers they are very helpful its slowly getting fixed.
Brendan

That hole in the pan rail I was talking about is pretty small - I'm guessing about 0.080" in diameter. If there is still pooky in there it will affect 4th gear for sure and maybe 2nd. If it's plugged, about the only thing you can do is remove the 4th gear servo and blow air into the passage. But I'm not totally convinced that is your problem or that all the trouble of inspecting the passage and blowing it out will help. Your TV adjustment sounds right provided this is an OEM setup. If the 700R4 or throttle body/carb is a retrofit, you might have to adjust it differently. Just know that the TV cable is not a twiddle point for changing shifts like the old vacuum modulators were.

its is the normal setup for the tv cable. its running alright right now. but its going from being good to shifting weird. its random. i did adjust it properly im just wondering if maybe there is something wrong with the tv cable. we are dropping the pan this weekend hopefully we will find whether its major or not. thanks for the help any other advice good or bad is welcome thanks guys. also is taking off the servo easy. any precautions? i have access to any tools i need.
Brendan

Getting the servo cover off is tricky. The factory uses a jig to remove it. The jig bolts to the pan rail and has a pivot point with a lever attached. One end of the lever rests against the servo cover. When you move the other end, the cover is pressed into the case so you can pop the steel snap ring out. I usually engineer something to press the cover in and have even used a hammer handle with brute force and a helper to pop out the ring. It's not a piece of cake to do, especially in the vehicle.

Once the snap ring is removed, the cover will pop off, though you might have to use some channel lock pliers to grap the center of the cover and pop it off.

Inside the servo assembly is a couple of pistons on a pin with springs. I don't recall if you have to remove those to see the passage to the pan rail or not.

If you think you need to go down this path, I'd drain the fluid and remove the pan first so you can inspect the hole to see if it is plugged. If it is, perhaps a pick probe or guitar string would fish out the RTV boogar. Otherwise, if it's clean, save yourself the trouble of removing the servo cover etc.

The vent hole is quite small. Here is a photo, showing where it is. As you can see, it would be very easy to plug if RTV was used ! Don't use any on reassembly !

http://i263.photobucket.com/albums/ii152/tjs69_photos/Transmission%20ID/trans1.jpg

I would clean it out with a small drill bit by hand ! and suck out the pieces with a shop vac.

ah ya that makes sense how that could get plugged all this info is great im going to drop the pan today and ill post what was wrong tonight sometime thanks a lot guys uve been more than helpful
Brendan

hey guys dropped the pan and changed filter fluid and gasket runs good. but not completely top notch. we found a bic lighter in the shifter under the console it wasnt allowing it to fully go into gear. adjusted the tv again. and she runs pretty damn good. anyone got the shift times compared to rpms tho. just to compare see if im in the ballpark. and also whats that tranny cleaner u put in that works wonders( just to make sure theres nothing in there) You just add it to a full tranny and it does its work. there were no large chunks of anything in the tranny(metal or rtv) seems to be pretty darn good but id just like to check so anyone that has shift times to compare to would be great. thanks so much
Brendan.

http://i263.photobucket.com/albums/ii152/tjs69_photos/Transmission%20ID/700rpressures.jpg

I'd stay away from "miracle in a can" stuff for automatics. Most of them soften the seals. At best, they may buy you a few hundred miles, and more than likley will cause a pre mature failure if everything is in good shape. Tranny fluid by design will clean sludge out of critical places and deposit it in the bottom of the pan where it will do no harm.

alright. well i guess heres the last go at this.. i have the specs on my tranny and it says theres a seal at the end of the throttle valve cable. if correct could this seal be stuck open or worn. i mean even if the throttle valve cable was adjusted properly if the seal was whooped then it would be pointless. could this be it. i need to make sure my tranny is good cause i plan on selling my car i dont want to sell it messed up cause thats not cool. if this seal is replaceable does the whole tv cable need to be replaced with it. thanks this will be my last try unless i find some other great idea.also everything in the specs in the problems im having refers back to the tv cable or the valve body. seems to be where somethings going wrong according to gm specs and such. whats the best way to replace the cable if needed. sorry for all the stupid questions i am not a tranny guy!
Brendan

I think the seal you are speaking of is in the valve body (throttle valve). Replacing the TV cable won't help. You could be guessing at parts for a long time. Either take it to a transmission shop or be honest about it when you sell it.

ya i guess. could be a million things at this point. oh well everything else is new and 700r4's a dime a dozen so well see. thanks for everything guys !
Brendan

oh and last but not least if this helps. the car surges about two hundred rpms when driving. anytime over 2000rpms usually does this help? never used to till now. kinda seems odd now that i think about it.