I did a search but did not find this exact problem. My 700 on my old beater will not upshift unless I let off the pedal to about 1/4. If I give it anymore it will downshift and the engine will rev up but no power is going to the wheels.
This trans. was rebuilt about 15,000 miles ago and i am 100% sure the tv cable is adjusted correctly. It has proper fluid level and it does not smell burnt. Non cc and it is a lock-up.
i read on some other posts about checking for a sticking gov. on similar problems. Could that be it and if so how do I get to it?
I have rebuilt engines and installed 700's but I have never had to do anything on the trans. except replacing a T/C and tv cable.

Thanks for any help

 

when i read the title to the thread it sounds like the TV cable exactly. i would make sure u adjust it correctly... there are a couple ways to mess this up. i just did one on my 86TA 2 days ago. look at tvmadeez.com

otherwise if that is good. i had a simular problem when i was driving around, no noise, just all of a sudden no power to the wheels no matter how much it was reved. had to drive mile at 4500rpms at 5mph to get it home. the tq conveter exploded and whiped out the entire trans. it had no fuild level loss, no burnt smell... it was all internal.

how was it driving for the other 15000 miles u had it rebuilt for? anything changed since then?

 

It was perfect till about 300 miles ago. It started to not shift into 3rd unless I let off the pedal. Now it is 2nd and third. It is perfect as long as i don't try to give it more than about 1/3 throttle. If i try to give it more it just revs and it acts like it is trying to shift, feels like i am pushing the throttle up and down, but will not until i let off. I have the tvmadeezee on my 85 and my p-up has a stock gm so I am positive it is correct.
I have a trans. pressure gauge. Would the line pressures tell me anything?

 

yea stock line pressure is around 160psi... any lower and it wont shift properly... i would see if theres fluctuations in the pressure. if you installed larger boost valves like me u would be running high pressures almost max like 240-280psi.

sounds like a valve body problem. maybe something is stickin

 

I re-read my post and realized I should not have said it revs. It doesn't rev up it just will not shift.
I went out and pulled the tv cable off at the carb, put it in D and pulled the cable all of the way out. If I am remembering right shouldn't it act like it is trying to move and the rpm's drop some? I also put it in 2 and floored it and it was fine till about 4000.

 

these are the pressures with tv dissconnected
p...80
r...90
n...80
od...80
d...80
2...115
1...70

dissconnected with tv pulled fully out

p...150
r...80
n...150
od...120
d...120
2...115
1...80

R and 1 seem too low. When I pull the tv it does not increase. I know my bowtieOD has 300 psi in R.

Anyone have an answer?

 

those pressures are pretty low. im not really following wat u mean when u say ur pulling it all the way out. easy way to adjust the TV is to push the D shaped button in and then max out the throttle linkage. then let go of the D shaped button. then have some one max out the throttle from the inside with the pedal... and make sure the pedal when pushed to max is the max it would be at the carb/TB. if there is a difference then u have to adjust for it. but if it is the same then u should be good. thats how u adjust the TV. this should be done in park without the engine running. u should not be doing it in the D position.

as far as the pressures... i would throw in the boost valves they will increase line pressure.... so does the B&M shift kit (wrong way tho) vs the transgo shift kits. im pretty sure bowtieOD uses the boost valves to increase line pressure which increases clamping pressure on the clutch packs.... its needed for higher HP applications.

u shouldnt be driving it etc with the TV disconnected u will cause major issues.

 

You most likely have a stuck TV valve. Install a modified TransGo Shift kit. It comes with a non-stick TV valve, the Corvette servo, large boost valves, etc. This is assuming that the clutches and band are still in good shape. This will solve the problem and much more.