I have a 99 blazer 4x4. When you shift from park to drive or drive to reverse there is a clunk comming from the area of the TC. Also while driving if you let go of the gas and step on it again it clunks. If you have any ideas please let me know...

 

check ur u joints

 

Could just be drivetrain slop. It wouldn't hurt to check your u-joints though.

Ofcourse, if it is actually coming from the area of the torque converter, it is possible that you have a broken flex plate.

 

it means your truck is getting old, just like all blazers?! any who your t-case is chain driven and when something is new everything is nice and tight. Well after 11 years things like your t-case get a little slack in emm, this is tottaly common and will not hurt the truck at all, the only thing you can do that might help with you CLUNK noise is drain and fill the fluid with mobile 1 that helps with the noise does not illiminate it tho hope that helps man

 

I had just noticed that the drive shaft turns a bit before the wheels move, is this normal or is contributing to the clunk?

 

Yes, normal. There is some play in any gearset. Yours may be excessive, but without getting into the rear differential and actually measuring the back lash and contact patch, you really will not know.

 

Just wanted to let yas know that it was my front universial on the rear drive shaft that was bad...i found out the hard way today on the highway. The ujoint broke and the drive shaft fell to te ground and bounced around and beat up under the truck quite bit.

 

Ouch. Sorry to hear that. Hope you can fix it without problems!! The T-Series trucks have 2 u-joints on the rear drive shaft?
My truck has the same issue with a "clank" coming from the rear (been doing it for 2 years) when I put it into reverse or drive from park.
Makes me want to ask Pep Boys check it out when I take it in tomorrow for the oil lines and tranny cooler.......

 

Yea i got them fixed. I recommend getting us done very soon. We thought we would have just a bit longer...i guess not. Luckly the vibration from it caused us to be only going 80kph if i would have been going faster im sure it would have done a lot more damage. I replaced them both rather then just the one. It was fairly easy to do once i got them out. They were the factory ones so they were glued, cemented and clamped...you know factory parts. Just get yours check soon so your not stranded.