Belt Tensioner Failed at 40k Miles

[Mcscott]

Any idea what caused this? It threw the belt off and it was still intact. The housing is bent and cracked. I replaced the belt and tensioner and have driven it 300 miles with no issues so far.

 

[BoostN]

This is the first I've heard of this. What did the motor do when it threw it off?

 

[Mcscott]

It issued an overheat warning and a service charging system message which got my attention. The temp gage was pegged, I'm surprised it didn't warn me before it got that hot. It's odd to me how the housing got cracked and bent like that. Changing it was really difficult.

 

[gemarsh]

View attachment 1045View attachment 1046Any idea what caused this? It threw the belt off and it was still intact. The housing is bent and cracked. I replaced the belt and tensioner and have driven it 300 miles with no issues so far.

Was there any noticeable squealing? Almost looks like the bearing failed and destroyed the mount.

Haven't heard of this. gm has revised the T1 6.6d belt tensioner, with a new part number. Old design used a plastic pulley. I have heard of the plastic failing. They switched to a steel pully.

That 3.0 pulley looks like a beefy assembly. Could be a fluke or could be chinezium bearing.

Did the new part look the same or revised in someway?

 

[Mcscott]

Was there any noticeable squealing? Almost looks like the bearing failed and destroyed the mount.

Haven't heard of this. gm has revised the T1 6.6d belt tensioner, with a new part number. Old design used a plastic pulley. I have heard of the plastic failing. They switched to a steel pully.

That 3.0 pulley looks like a beefy assembly. Could be a fluke or could be chinezium bearing.

Did the new part look the same or revised in someway?

There wasn't any noise when it failed and the new part was identical to the old with steel rollers. The bearing failed and the housing where the roller bolts on is cracked and coming apart. I'm curios which happened first, either the cracked/bent housing cause the bearing to fail or the bearing failure cause the housing to crack and break.

 

[gemarsh]

That's why I was asking about a abnormal sound. You'd think a bearing failure would make noise before a catastrophic failure.

Thank you for posting about this issue.