Transmission Woes
Thread Starter
Instructor
Joined: May 2007
Posts: 208
Likes: 0
From: Houma La
Transmission Woes
Car been sitting up three months , been working on interior.Run engine on a regular basis in driveway. Today finished install of LED tail lights.
Cranked her up and took a ride and automatic did not shift correctly.
Reverse slipped and then grabbed. put into drive and ok did not shift into 2nd easily and did not go into third. Dash center shifter console not in and upper gauge console not in. Does this have anything to do with it? Is there something electrical I may have to plug to shift correctly? Help. TH350 350 '78
Cranked her up and took a ride and automatic did not shift correctly.
Reverse slipped and then grabbed. put into drive and ok did not shift into 2nd easily and did not go into third. Dash center shifter console not in and upper gauge console not in. Does this have anything to do with it? Is there something electrical I may have to plug to shift correctly? Help. TH350 350 '78
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Sounds to me like it's low on fluid. Check the fluid level when it's hot.
Also, make sure your shifter is getting into the gates of the detent and it's not riding the fence on the gears.
Finally, check the vacuum line that goes from the manifold down to the transmission. Without engine vacuum it won't shift.
Also, make sure your shifter is getting into the gates of the detent and it's not riding the fence on the gears.
Finally, check the vacuum line that goes from the manifold down to the transmission. Without engine vacuum it won't shift.
Le Mans Master
Joined: May 2006
Posts: 7,708
Likes: 266
From: indy indiana
I am wondering if your trans filter isnt getting a bit clogged ,but this doesnt really sound like the problem.While idlesing the engine,the trans pump continues to work,but nothing else is "working" and staying lubed.Sorry,just done know enough about automatic to be much help.
Thread Starter
Instructor
Joined: May 2007
Posts: 208
Likes: 0
From: Houma La
Thanks guys. Started raining today and expect alot for a few days. Will check this all out when dry. I am not sure where the detent is or the module. I think I can figure the vacuum to tranny.
Race Director
Joined: Jul 2004
Posts: 12,713
Likes: 329
From: Scottsdale Arizona
I agree with the above. Sounds like fluid is low. Remember to check it with the car running.
If this isn't the problem, the vacuum is the next best bet. Likely to be the rubber hose down on the passenger side of the tranny from the metal line to the modulator valve (cone shaped thing that sticks out). May even have just come off there. Still, even with the valve off, it should still be fine in reverse.
If this isn't the problem, the vacuum is the next best bet. Likely to be the rubber hose down on the passenger side of the tranny from the metal line to the modulator valve (cone shaped thing that sticks out). May even have just come off there. Still, even with the valve off, it should still be fine in reverse.
Racer
Joined: Jan 2006
Posts: 256
Likes: 0
From: Norfolk VA
I had the same problem with my TH400, had a slow leak and the pump lust suction. The weird part was that when I pulled the dip stick, it looked ok on fluid. When it's too low and the pump looses suction there will be a vacuum sound when you pull the dip stick.
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Thread Starter
Instructor
Joined: May 2007
Posts: 208
Likes: 0
From: Houma La
Fluid was a bit low added and still will not shift into third. All of a sudden reverse starting makeing noise and now no reverse at all. Could hardly get the car to back down the rhino ramps. What now? I am putting her up on jack stands to thoroughly inspect tranny and all hoses,cables and whatever. Will keep ya posted and please send more suggestions.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
OK, the fluid is looking 'normal', the vac line to the rear valve is hooked up to the mani vacuum, the kickdown cable into the tranny is hooked to the carb per stock spec....and functions from what you can see....
those are the only two signals a 350 turbo has to determine gear selection, other than the shifter....
and you sure the thing is in position correctly...no changes on the cable adjustments...slide it throug the gears gently without paying any attention to the gates on the shifter itself in the console....
if no go......you gotta bad tranny....
NOW is the time to consider overdrive auto for fuel economy and freeway speeds.....
but if it's a city car with no extended cruising at 60++ don't bother, ....
those are the only two signals a 350 turbo has to determine gear selection, other than the shifter....
and you sure the thing is in position correctly...no changes on the cable adjustments...slide it throug the gears gently without paying any attention to the gates on the shifter itself in the console....
if no go......you gotta bad tranny....
NOW is the time to consider overdrive auto for fuel economy and freeway speeds.....
but if it's a city car with no extended cruising at 60++ don't bother, ....