Ok so I currently own a 2006 Monte Carlo lt. It was bought in June 2013 with 24,xxx miles on it. It just hit 73,000 and broke down. I started off from a red light and it almost instantaneously started grinding very loud. The RPM's and speedo were shooting up but it would not move. It would make this grinding noise in every gear including neutral and the car rolls in park. It starts up and runs fine but will not move. Not sure what is wrong. Could it be a blown trans or possibly a broken cv joint? Has this happened to anyone else? Any information would be greatly appreciated

 

Sorry to hear about the trouble with your Monte
I am sure those who have much more mechanical knowledge than I will be on the forum shortly and will be able to get you pointed in the right direction. In the mean time, you could try using the search function above to see if someone else has posted in the past about this problem.
Welcome to the forum!

 

Dan,


Unfortunately your and my car are notorious for weak transmissions. I have an LS4 had it from the day she was born and I have babied it.

I have heard that our transmission in the LS4 are carryovers from the 3800 and not really meant for the high torque our LS4 produces

Yep sound like your tranny gave up the ghost.

*** EDIT *** I am assuming you have the LS4 V8 ??? *****

 

Tadcaster,

I have heard before that the 4T65E is a weak transmission, and I have heard the LS4 eats transmissions for breakfast. I have the 3500 V6 so I don't even have the heavy duty trans. I didn't exactly baby mine though. I did a lot of racing and ran it a little hard. But I figured it was the trans I just wasn't entirely sure. No check engine light came on and it didn't bring up any codes

 

A test drive from a tranny mechanic would be the acid test. Sounds really like a rebuild is in order though

 

Dan:
I'm with Tadcaster on this one..
It definitely sounds like you detonated the trans..Especially if it wont hold in Park!

Considering yours is an LT and not an SS... you don't have the heavy duty trans... These transmissions aren't meant to be beat on..Thats for sure...
But generally when there not well maintained.. anywhere from 80,000 to 120,000 miles these transmissions start to fail... or show signs of wear issues.. But I'd confidently say you need a new trans... Unfortunately

 

Thanks for your input guys it's much appreciated. I kind of figured it was the trans and I've already found a new one. The other thing I was thinking it could be was the splines on the transaxle,s where it goes into the transmission, could be stripped off and it's not catching and that's why it's rolling in park. I heard they are easy to strip so it could be a possibility. I found a video of a van with the same 4T65E trans blowing it doing a burnout and it made the same loud grinding noise when it blew