transmission pump, internal damage?
Asked by ghicks77 Mar 30, 2017 at 07:49 PM about the 1985 Chevrolet C/K 10 Silverado LB RWD
Question type: Maintenance & Repair
I just replaced a 700r4 tranny with a th350
because it was slipping and after tightening
everything and making sure everything was hooked
up i put my truck into reverse to test drive it and it
goes into gear but the truck doesnt move, u cant
feel or hesr it shift but if someones underneath
they can see it shift and i have to rev the engine
up in order for it to move and when it does move
its very slow and its kind of on a hill and when i
went to put it in drive it rolled back a little bit but
then it just wouldn't move at all almost like its not
getting enough power to pull up the small hill, the
fluid was just changed and is still pink and the
gear, torque converter, and driveshaft are all
rotating its just not moving, any ideas?
23 Answers
If the driveshaft is rotating and the car does not move maybe you have a broken axle.
So do you know the trany you put in was good? And you have the fluid full?
Rowe - this poor fellow has several posts on his problem. He puts up a new post rather than replying to his original post - makes it hard to follow.
I hate that, run into that all the time.
i tried replying to other comments but its not letting me and yea the tranny was good, i drove it in another truck for 45 mins and not a problem and i drained the old fluid and got a new filter and filled it back up so the fluids good too
As I said in the first post here - if the drive line turns but the truck does not move I think you have a broken axle. The limited slip clutches in the differential might make the truck move a little at least until they give up.
Was the torque converter installed properly? Rotated and pushed back so you can't get your fingers in behind it, or so it sits back below the bell housing mounting surface? and is the vacuum line hooked up to the modulator valve?
The axle looks good and it was running good before I changed the transmission, and I think rowe found the problem because there is no vacuum line on the modulator valve, where can I get one and how much would it cost? and where does the other end of the line from the modulator connect to?
They will have that valve at the auto parts store, you would need to know what vehicle that trany came out of. And it is just a vacuum source to hook up too.
oh okay it has the modulator but there is no line, does it hook up to a vacuum source on the intake?
and could that line not creating a vacuum cause my truck to do this?
Yes it just hooks into a vacuum source up on the intake, you may have to "T" off of something. On the shifting, it does affect the shifting, but not sure if it could completely stop the trany from working. Are you sure you have the torque converter seated all the way in? Did you spin it on while pushing back on it? When installing the trany, there would have ben a gap between the torque converter mounting and the flex plate.
yea I spun and pushed it, theres no gap between those and could it b that my tv cable isn't tight enough?
No unless it is too tight. Thats just for passing gear. Could you spin the torque converter when the trany was bolted up?
It should have turned no matter what. What was the vehicle this came out of and the year?
Gotta take my dog for a walk, be back in a bit.
it came out of a 1986 c10 Scottsdale, and how easily should it move because I can move it in park but its kind of hard and my truck originally had the th350 but someone swapped it with the 700r4 and I'm swapping it back
Long as you could move it by hand. So what I am finding out is there doesn't seem to be enough pressure building up in the transmission to work. You say you changed the filter, from what I am reading if that is not installed correctly it could not pick up the oil to circulate. Was that trany filter pushed up in there all the way? And also it is just intake manifold vacuum for the modulator valve and if that is not hooked up it could not shift into gear. Need to look at these things. There should be a oil pressure test port by the transmission lines to check the transmission pressure.
okay, I might just go ahead and do a new transmission filter again bc I had a friend do it for me, and ill check those things and get back with u
That filter gets pushed up all the way, shouldn't be hanging down at all.
alright ill check to make sure hes got it in there right, I'm hoping I don't have to get a new tranny
