GMC Troubleshooting Questions? Ask a Mechanic for Answers
Hi, welcome to Just Answer. I’m Ron and I’ll be helping youtoday.Before we get started though, Please understand that I don't knowyour skill level or tools you have to assist us. Also understand thatI can't see, smell, hear, or touch the vehicle either, so patience isappreciated. JA is a great Q/A site, but it does NOT replace arepair shop.My goal is to make you happy and get a great rating in return formy time. Sometimes I have to give you bad news that I know youdidn’t want to hear, so please don’t shoot the messenger. They'll know what to do.
here is a TSB for that noise you're hearing.
Thanks , Ron
good morning my name is ***** ***** I will assist
has anyone check the rear motor mount?? very common for separating and jumping up and down during acceleration and deceleration.
yes, I agree. the motor mount I am referring to is the transmission mount at the rear crossmember. when it separates, the transmission jumps up and down. very common failure due to the stress.
take a good long screw driver to the rear of the trans or transfer case. pry up using the cross member. see if it moves up and down. you can see the mount very easily
I cannot answer that. I am here and not there to look at it. they may have left bolts loose or the nuts securing the mount to the cross member
did you have the noise prior to replacing the transfer case???
I wish I could tell you more but I am here and not there to determine the failure.
I would still check that mount.
I will be here
just checked and none found for this particular issue.
I will opt out and see if anyone else can help you further
Quick question was a used differential installed?
Ok this happens more then you would ever think.Have they tried another differential as well as checked the driveshaft?
You can just go under the truck and move it up and down and forward and back if there is excessive play the u joints in the drive shaft are bad and thats your issue its actually very common and should have been checked.
No up and down movement at all ? Also if the u joints are not installed correctly it will also cause this issue .I would focus here and if that checks out I can almost garuntee the rebuilt deferential is bad . I would start here next .