Hello I just got an 86 trans am, and it is my first vehicle. I am 19 years old and dont know much of vehicles and how to repair them but i would love to pursue a carrer in the automotive buisness. Anyway, the reason i am posting is because my father bought me this vehicle and i have been driving it for about a month and everything was great. It stalls once in a great while at red lights but thats not my main issue. I was driving down interstate 4 and got up going about 80 mph, which is the farthest i will go in this car knowing it only reads 80 and the car is old and original. Shortly after getting off the interstate i got at a red light and once i started to accelerate my car got up to about 30-40 mph and it wouldnt switch to third gear. I can drive it in second on the center consol operator and it will get going to about 50 where thats the fastest i can go in that gear. Once i put it into (D)drive or overdrive the car gets up to about 40 mph and then starts to rev up like its in neutral. I checked the transmission fluid and it looks great, now the filter i have not yet located and not knowing what i am doing i don't want to mess anything else up. I was going to go get a owners manual book for it next week, but i figured with many Pontiac owners i could also find help on here. Im looking to keep this car and eventually fully restore it so please dont come at me with offers to buy it or demands to sell it. Other than that any advice is greatly appreciated!

 

Usually the 3-4 clutches and/or the forward clutches wear out as they take the most use (shifting between 3rd and OD all day). If you have bent, crimped tranny cooler lines, or have burnt fluid that could be the issue and requires cheap parts but a destroyed transmission if you arent careful.

If its a valve body related issue or a pump issue you can get away with a lot less work.

If it is the TCC solenoid, its in the valve body. I highly recommend buying an ATSG manual on a first design valve body 700r-4. It will show you how to do the correct procedure for accessing and replacing the TCC solenoid. Not a terribly hard thing to do, but you must be careful and pay attention to details.

 

when you checked the trans fluid, was the car up to temp and idling? if not, check it that way. it will read way higher than it's supposed to be if you check it with the engine off. if it's low (and it probably is), then you add more fluid thru the dipstick tube, being careful not to over fill it. a half a quart can make the difference between the trans not shifting right and working perfectly..

also check the tv cable- it the cable that runs up from the trans to the carb or throttle body. the trans uses the position of this cable to decide when to shift and how hard to do it.. if the fluid hasn't been changed in a while, the valve inside the trans can get stuck.. unhook the cable from the throttle arm and pull the cable out as far as it will go and release it a few times. be careful not to pull too hard, or you will knock it out of adjustment and have to learn ho to set that back to the proper place.

if none of that works, then it's time to check the filter- you have to drop the trans pan to get to it.. have fun with that- it can be a messy job for even an experienced mechanic because GM decided to save 10 cents on every car they built by not putting a drain plug in the pan.. anyways, you are looking for a lot of metallic goo in the bottom of the pan and in the filter itself. if the fluid is all sparkly and there is a lot of stuff in the pan, then you might be able to get by for a while with a new filter and fluid, but the trans is on it's way out..

 

Hi--- I also have problems with my 700R--- so I dropped my pan and found a build up of film-not metallic-in the bottom of my tranny pan. But since I have only owned this car very shortly- could this silt build up on the pan be from years of never changing tranny fluid and filter by the previous owner. I had to use a scrapper on the pan to remove this build up, It was like a very fine "mud" less than 1/16" thick. Is my tranny on the way out too? I bought LUCAS - and hope that it will help my being stuck in 1st gear..... I will inspect the Tv cable--- Can LUCAS tranny additive help???? thanks

 

if tranny will not upshift out of 1st gear,the plastic governor drive gear may be broken-not a major job to repair.

 

Plastic governor drive gear? Would it be difficult for an avg firebird guy to fix-- or should I bring it in to a Lee Myles or Aamco.

 

I appreciate all of the tips and pointers. i did what i could, changing fluids and filter etc... nothing happened so i just decided to take it to my transmission guy and he test drove the car.. well the outcome was the 3-4 clutch are burnt out. apparently its going to be 1200 to rebuild the tranny including labor. I found one for 300 and i have a buddy that will help me free of charge. So i will keep the thread updated once i put the new transmission in. Again thank you guys for your help!

 

Good luck, hope the used one has been rebuilt or you maybe wasting your time and money..