I've got an 05 GMC with the Duramax. When you kill the ignition, there is a quick belt squeal for a second or two as soon as it stops idling. Anyone else heard of this or have any ideas? It almost sounds like the pulleys are stopped and the belt keeps moving for a second or two.

Same thing happens on my truck. I also get a odd sueal sqeek just after startup of my truck. About to take mine into the stealer and see what they say.

The squeak at shutdown is caused by the motor stopping quicker than the accessories and the accessories are causing the squeak. I believe a higher quality belt may possibly fix that. Mine does it too.

I've got an 05 GMC with the Duramax. When you kill the ignition, there is a quick belt squeal for a second or two as soon as it stops idling. Anyone else heard of this or have any ideas? It almost sounds like the pulleys are stopped and the belt keeps moving for a second or two.




ditto

Normal according to my dealer. I think there's a TSB on it somewhere that states just that.

6.6L LB7 LLY Diesel Engine Drive Belt Chirping on Shut Down - kw noise #PI01242A - (Feb 17, 2004)

6.6L LB7 LLY Diesel Engine Drive Belt Chirping on Shut Down

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When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Condition/Concern:

01- 04 C/K 6.6L ( LB7 LLY) diesel engine drive belt chirping on engine shut off

Recommendation/Instructions:

NORMAL CONDITION FOR DIESEL ENGINES

It is a characteristic of all diesels and is caused by the rapid stop of the cranktrain due to the higher compression, as compared to a gasoline engine. It may or may not occur, depending on variations in temperature, humidity, engine compression, internal engine friction, belt condition, tensioner spring tension, tensioner position at time of engine stopping, pulley condition, drag imposed by accessory drive components, where the engine is at when it is shut down, and any other possible variables that affect how fast the engine comes to a stop and variations on belt tension/friction.

I have belt squeel on start up till it warms up. Then its barely noticable at that point. So a squeeling belt on start up normal? Annoying as hell and sounds like the engine is broken lol. Going to the dealer tomorrow to see what they say.

I have belt squeel on start up till it warms up. Then its barely noticable at that point. So a squeeling belt on start up normal? Annoying as hell and sounds like the engine is broken lol. Going to the dealer tomorrow to see what they say.
You may want to do a search on that. If I remember correctly, there was a piece redesigned to address a belt alignement issue, but I think that was for the 04 models. I think it would be fixed for the 05's. I don't think the dealer will do anymore than put some belt dressing on it or replace the belt with the same. You might want to go try a Gatorback belt or equivelant.

6.6L LB7 LLY Diesel Engine Drive Belt Chirping on Shut Down - kw noise #PI01242A - (Feb 17, 2004)

6.6L LB7 LLY Diesel Engine Drive Belt Chirping on Shut Down

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When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Condition/Concern:

01- 04 C/K 6.6L ( LB7 LLY) diesel engine drive belt chirping on engine shut off

Recommendation/Instructions:

NORMAL CONDITION FOR DIESEL ENGINES

It is a characteristic of all diesels and is caused by the rapid stop of the cranktrain due to the higher compression, as compared to a gasoline engine. It may or may not occur, depending on variations in temperature, humidity, engine compression, internal engine friction, belt condition, tensioner spring tension, tensioner position at time of engine stopping, pulley condition, drag imposed by accessory drive components, where the engine is at when it is shut down, and any other possible variables that affect how fast the engine comes to a stop and variations on belt tension/friction.
Thanks very much! I had a feeling that was the cause, it's just nice to get a confirmation of it!

Ok guys, here's the update on my cold starting/running belt squeel. Dealer replaced the belt on the truck and as of bringing the truck home, no squeel, mind you it was also the first time the temp was above 0c but we are back down to 10 below tonight so I'll keep my ears open.

yeah i had them replace the belt for squeaky when idling cold mine squeaks also on shutdown