tranny

[GARY BRUNGARD]

Noticed a vibration in the cab that resonates through the whole truck. I opened the windows to hear it better and it only happens in overdrive at about 45mph with little gas. You can hear like a rattle rumble from under the truck, has anybody had this trouble?

[broughy84]

Year, model, engine size, tranny? need some info.

I had a back rattle and vibration assotiated with speed and rpm that only happened going down the road in the beginning and it was my flywheel. It was cracked. Crawl under your truck and make sure you cant move your flywheel back and forth also check your torque converter bolts. I don't know what year truck so I don't know what tranny you have, but on the late eighty's early ninety's they have the 700r4. Definatley check those to things. Also how long has it been since the transmission has been serviced? Fluid/Filter?

[GARY BRUNGARD]

Hey whats up , yeah I should have said 98 silverado with a 4l60e trans, 350 z71. Sombody also said check the u joints?

[SpitAndDirt]

Check with the dealer to see if you have a update for your trucks computer available. It could just be a simple reprogramming issue. I have a 96 Z71 and I had a few out there. You might have some also. Hope this Helps -Chris

[GARY BRUNGARD]

Whats up chris, what kind of updates would be needed or is that my ecm lost data and needs reprograming

[desertmike1]

Your best bet would be a Tranny shop before you tear it up, (assuming) it's your trans.
They can perform a PCM data streem test and compare that with how the trans is shifting, and then isolate electrical from mechanical.

mike