banging sound

[ericnj75]

when i put my 01 denali xl into rev. it makes a bang sound it only does it in these gear what could this be?

 

[mdtahoe]

Bad u-joint

 

[denalianyone]

It may or may not be a bad u-joint. My truck has been doing this for about 80,000 miles now (still have stock tranny) and I checked the u-joints numerous times...all is well.

 

[Modded]

GM does have some normal sound that is made in alot of theri SUV/Trucks, its called "driveline lash", someone help me out.......

 

[ericnj75]

its getting louder and it only does it park to rev.