Our Community is 940,000 Strong. Join Us.


Transmission rattling


m1a
11-22-2008, 02:55 PM
I have a 95 GM pickup truck. I have been having this rattling noise coming from the transmission up near the torque converter. It sounds like something might have come loose and is rattling around. I had the truck at the auto shop and they replaced the torque converter and checked out the flywheel. The flywheel is in good shape. They also did a tranny flush and replaced the filter. The old converter had minor cracks which is why they replaced it and I was hoping that would solve the noise issue but it did not unfortunately. The transmission does shift great otherwise.

I can hear this rattling noise when the truck is in park and when it is in gear and the noise is intermittent. While I was at the shop, we listened for the noise with a stethoscope and it was definitely coming from the area where the converter meets the transmission. I wanted to see if anyone had any ideas as to what could cause this noise? With the tranny shifting fine, should I just leave it alone or have a tranny shop look at it? The transmission is a 4L80E. The truck has 159,000 miles with the original tranny. Thanks.

HUNTERPAUL
11-22-2008, 04:44 PM
Somethinee I have found out over the years is nois on a vehicle will travel and lead you down the wong path. Usually any noise in a transmission will cause failure or make noise on only one gear and then quiten when shifting into the next gear. I have seen many exhaust converters make noise like this. I have also seen many broken flywheels, which like to brake arount the crank bolts, and are not always easy to see. The exhaust conver is easy to diagnose , just hit it with your hand to see if it rattles.

p0peye_34
11-29-2008, 07:28 PM
Sounds like there is something lose under the truck.

Probably a heat shield or skid plate. Get under the truck while it's running and have an assistant step on the gas (or do whatever it is that causes the noise). Grab hold of heat shields, skid plates and whatever you can get your hands on to see if it stops. Be careful of hot exahust and moving parts!

If it doesn't increase in intensity with speed or RPMs, or cause problems, it's just an annoyance rather than a problem.

TR

Add your comment to this topic!