Th350 shake from 2nd to 3rd

[squarebody_1985]

I have a th350 that shakes the whole truck when you first start driving it in the morning and shifting from 2nd to 3rd. Shifting back down into second on the column and getting the rpm and speed up then shifting back into drive usually fixes it. Once it gets warmed up it acts fine. Anyone have any ideas what could be causing this?

 

[NickTransmissions]

I have a th350 that shakes the whole truck when you first start driving it in the morning and shifting from 2nd to 3rd. Shifting back down into second on the column and getting the rpm and speed up then shifting back into drive usually fixes it. Once it gets warmed up it acts fine. Anyone have any ideas what could be causing this?

How long has this been happening? Any recent work done on the trans?

Sounds like it could be torque converter (stator intermittent failure) and/or tc drainback...anything else, I would think it would happen cold or hot...

 

[squarebody_1985]

How long has this been happening? Any recent work done on the trans?

Sounds like it could be torque converter (stator intermittent failure) and/or tc drainback...anything else, I would think it would happen cold or hot...

It's been that way for a while. To my knowledge it hasn't had any transmission work done.

 

[NickTransmissions]

It's been that way for a while. To my knowledge it hasn't had any transmission work done.

There isnt too many things transmission-related that can cause your symptoms and even less when the pattern as described (symptom presents when vehicle/trans is cold and goes away when at op temp). Check your flexplate for cracks or loose TC bolts just in case though dont think thats the problem. Check the rear mount also (good idea to check the mount on general principles if you havent already).

Drainback is my guess and if that is the problem and worn stator bushings are the cause (which they often are), trans will need to come out for overhaul.

 

[squarebody_1985]

There isnt too many things transmission-related that can cause your symptoms and even less when the pattern as described (symptom presents when vehicle/trans is cold and goes away when at op temp). Check your flexplate for cracks or loose TC bolts just in case though dont think thats the problem. Check the rear mount also (good idea to check the mount on general principles if you havent already).

Drainback is my guess and if that is the problem and worn stator bushings are the cause (which they often are), trans will need to come out for overhaul.

Thanks I'll check that stuff out.

 

[avianes3]

my TH400 did the same thing. Took to my Transmission specialist. It was the vacuum line to trans modulator that had melted.(Hot Header). Vacuum line goes from the trans modulator to Intake maifold