Transmission Issues
April 26th, 2019, 10:47 PM
#1
Transmission Issues
When I first bought my van (1986 G20 5.7 350) I did all the fluids on it. I know you're not supposed to, but I changed the transmission fluid out in one go. Cleaned out the pan, got a new filter, gaskets, etc. I torqued everything down correctly and added the amount of atf specified in the manuals (Chilton, Haynes, owner's). I shifted into each gear with the brake on, all the way down the column, back up into park. At no point did it feel like it was shifting or trying to. When I tried to shift into gear, nothing. When I pressed the gas, nothing. I checked the dipstick while running and it registered as full while hot. Just to be sure, I added a little at a time to see if it helped. It did, and eventually I got to a point where I could drive it slightly. I'd have to slam on the gas and it would just barely start to move. It got to the point where I had added a total of 8 or more quarts to the pan, which seems excessive at the least.
The bolt pattern on the tranny pan matches what would be a TH400, but the 350 is what comes standard with these as far as I'm aware. When I got the replacement parts, they were ordered based on the bolt pattern as well, which, again, seemed to indicate it was a 400.
Either way, I still can't get gears to engage or even seem like they want to. Can this be a symptom of adding to much atf? Did I really wash away all the friction material by putting new fluid in there? What did I f*** up?
The bolt pattern on the tranny pan matches what would be a TH400, but the 350 is what comes standard with these as far as I'm aware. When I got the replacement parts, they were ordered based on the bolt pattern as well, which, again, seemed to indicate it was a 400.
Either way, I still can't get gears to engage or even seem like they want to. Can this be a symptom of adding to much atf? Did I really wash away all the friction material by putting new fluid in there? What did I f*** up?
April 27th, 2019, 12:42 AM
#2
I'm here for the party
ok lets start with the basics. the th350 would of been phased out by 85 and the 700r4 would of replaced it. but you really wouldnt find them in anything above the 1500 pickup (not sure about the vans). the th400 would of been in most 2500s.
but anyway theres no issue with changing the fluid on one of these at any millage. most people forget about the fluid and burn it up then once they notice issues with the trans they try to fix it by changing fluid and by this time their trans is already fried and they blame the new fluid on frying the trans when it was neglect that did it.
i dont care what the manual says about how much fluid but check to see how much came out. total fluid should be about 12 qts, but if you have abigger trans color then that will ad to that and some might even have a bigger trans pan. i would add a qt or two more, if your trans is fried already it cant really hurt anything.
but anyway theres no issue with changing the fluid on one of these at any millage. most people forget about the fluid and burn it up then once they notice issues with the trans they try to fix it by changing fluid and by this time their trans is already fried and they blame the new fluid on frying the trans when it was neglect that did it.
i dont care what the manual says about how much fluid but check to see how much came out. total fluid should be about 12 qts, but if you have abigger trans color then that will ad to that and some might even have a bigger trans pan. i would add a qt or two more, if your trans is fried already it cant really hurt anything.