Skaking/ vibration in overdrive

[93Chevy_1500]

I got my timing issue all figured out but now when my truck shifts into overdrive around 45mph it will skake the whole truck until i get up around 50 then it goes away as the mph increases. It doesn't do it in any other gears and shifts up and down perfect. Trans level is fine to. I have no idea where its coming from because i cant feel it in the steering wheel but i can feel the whole truck doing it. Any ideas? The trans is a 4l60e. My service engine light is on to but its running perfect and i have yet to flash the code.

 

[SAATR]

Sounds like you're getting some shudder when it's trying to go into lockup. TCC solenoid possibly, but I'm no transmission man! I'm sure somebody will chime in...

 

[93Chevy_1500]

Sounds like you're getting some shudder when it's trying to go into lockup. TCC solenoid possibly, but I'm no transmission man! I'm sure somebody will chime in...

thats what i thought to. But it doesnt do it when the rpms increase. and it didnt do it when i had my 4.3 in it.

 

[Southern Pride]

That's odd. I'm def no tranny man either but have you checked your driveline/ driveshaft? Does the driveline make any noises or does it just shake?

 

[SAATR]

I personally don't know why swapping motors would cause that to happen, but that really does seem like the case. Try holding your foot lightly on the brake pedal as you accelerate, and see if it still makes the vibration around that speed. The brake switch being active should prevent it from going into lockup, so if the vibration goes away then it has to be something to do with the converter locking up.

 

[93Chevy_1500]

That's odd. I'm def no tranny man either but have you checked your driveline/ driveshaft? Does the driveline make any noises or does it just shake?

it just shakes. no other noises its pretty weird.

 

[93Chevy_1500]

I personally don't know why swapping motors would cause that to happen, but that really does seem like the case. Try holding your foot lightly on the brake pedal as you accelerate, and see if it still makes the vibration around that speed. The brake switch being active should prevent it from going into lockup, so if the vibration goes away then it has to be something to do with the converter locking up.

i'll have to try it tomorrow. Man i better not have to pull this trans again...

 

[93Chevy_1500]

Also if im in it pretty hard and it doesnt shift into overdrive at around 45 and it shifts around 50 its smooth as can be.

 

[darren250r]

I would be investigating the converter like what was mentioned above. You might also go over the engine and tranny mounts to make sure they're tight and the rubber isn't torn. I'm thinking that when the TC locks up in OD at that low of a speed, its lugging the motor and could cause it to shake if any of your mounts are worn or loose.