Auto transmission shift shock between 1st and 2nd

[ck1938]

Hey there, I checked the auto transmission forums and the only similar post I could find indicated I should get a new TCU, which I've already done. So forgive me if I missed the posting that answers my question.

When the car shifts from 1st into 2nd there's this thunk. It feels like the car hits this threshold and needs just a little extra oomph to push through it. When the car gets that oomph it pushes through that threshold and jumps forward and you can feel and hear the shift inside the cabin. Vrmmm - THUNK- Vrmmm. When I'm going from 2nd to 3rd or into overdrive I don't have the problem. Something similar happens going from 2nd into 1st but not as bad. Not yet anyway. Any advice besides getting another TCU? They are kind of pricey.

 

[xioca]

Warm your car up and check the tranny flued level and make sure it goes all the way up to the hot line.

Mine used to kind of grind into a gear, this fixed it and seeing as it's free it doesn't hurt to check it.

 

[gsxgate24]

Im having tranny issues too. I'm an auto gsx and when I come down to a stop it grabs hard into first gear and slams me to a stop. Also after I start the car for the first time, I let it warm up and I drive up to the first stop sign my car kicks out of gear. I have to put it in park and shut the car off wait a second and start the car back up and then put it in drive and after that it doesnt do it again. just in like the first 30 seconds of driving

 

[jabinya]

When you check your transmission fluid level, make sure the car is in neutral and the E-brake is engaged. Checking the fluid level in park will give a different, inaccurate reading.

 

[ck1938]

When you check your transmission fluid level, make sure the car is in neutral and the E-brake is engaged. Checking the fluid level in park will give a different, inaccurate reading.

The fluid level is right at the hot line.

 

[ck1938]

Im having tranny issues too. I'm an auto gsx and when I come down to a stop it grabs hard into first gear and slams me to a stop. Also after I start the car for the first time, I let it warm up and I drive up to the first stop sign my car kicks out of gear. I have to put it in park and shut the car off wait a second and start the car back up and then put it in drive and after that it doesnt do it again. just in like the first 30 seconds of driving

Are you getting any error codes? Mine was doing something simlar and it turns out the TCU was the culprit. I'm just wondering if I might have bought the wrong replacement computer for my transmission.

 

[ck1938]

I think I might have fixed it. I've had a vibration in the lower gears too so I checked the motor mounts. The bolt holding the rear motor mount in place had fallen out. I jacked up the engine and replaced the bolt. Took it for a drive and the vibration was gone and the thunk seems to have disappeared. I'll update the post if anything chnages. Thanks for your help.

 

[gsxgate24]

does anyone have any idea what is up with my tranny?