4L60-E rattle

Posted by: NMBurb02

4L60-E rattle - 04/27/14 03:50 PM

To expand on the subject line, the Burb makes a rattle on cold starts and I am not exactly sure how long it has been doing so. It happens every time it is started, but it is pretty erratic as far as how long it lasts and usually rattles for a second, stops for a second or two, rattles, stops, etc. with no apparent pattern. I believe it stops once warmed up. I finally got around to crawling underneath to check it out and tracked it down to the transmission. When I put my hand against the transmission pan I can feel the rattle. The last pan drop and filter change was done just under two years and 20k miles ago by my regular shop. They used an ATP gasket and filter kit and Dex III fluid (not sure which brand). Could it be an issue with the filter? Something mechanical and the whole thing is about to grenade?
Posted by: Colt45ws

Re: 4L60-E rattle - 04/27/14 04:16 PM

I think I just read about someone else with a similar symptom on here and it was a cracked flexplate.
Posted by: NMBurb02

Re: 4L60-E rattle - 04/27/14 04:55 PM

Never mind. Please move on. Nothing to see here.

I just spent some more time down there to check to see if the noise was coming from further forward in the tranny and not actually from the pan to indicate that it might be a flexplate issue and while down there I started smacking things with the heel of my palm and when I hit the exhaust pipe about 6 inches behind one of the cats, the rattle became worse. I thought I might have a catalytic failure issue similar to that of the GP, but upon further investigation and smacking, I discovered that the rattle is coming from the rear O2 sensor on the driver's side. No codes yet and it passed a smog test a few months back with flying colors (it was making the noises at that time), so I guess it still functions properly. I could have sworn I was feeling the rattle in the transmission pan, but maybe it was just all in my head.