The only way to tell is to remove the belt and check for looseness (wobble) in the tensioner.Unless of course your belt is fraying, which is what my situation was.

 

Now you got me worried I have the Jacobs exhaust brake that requires a different belt and I would bet I could not get one at just any Mopar dealer. I do have the original belt and I carry it as a spare. I just looked at mine and tried to find play in the tensioner and It appears to be OK the belt also looks good, I have 75000KMs.or 46000miles on the truck.
Jim O

 

I am starting to get a squeel (very much like a belt squeel) when using my Ebrake. When I turn it off, no squeel. I suggested to the dealer it might be the tensioner or a bearing in something in the belt line. We will see what he finds out. Thanks for the heads up on this - - I will mention it to him.
Bob

 

Got the truck back this eve. New tensioner,belt,and tensioner bolt.Svc mgr. says they now have 3 xtra tensioners in stock as my rig was the 2nd one w/ this prob in the month of October.

 

For those getting paranoid on this I have not seen ONE occasion of this belt failure come through the shop yet......but when I do, I'll know what to get .

 

Tensioner part# 5086958. Belt part# 53041138