2021 6.2 Trail Boss

tadkins522 · June 23, 2021

Squeaking or squealing noise coming from engine as I come to a stop. I’m assuming it’s the DFM?? I’m about to but the Pulsar LT to disable it. Any input would be helpful, the noise is driving me crazy.

American Cobra · June 23, 2021

Yes its the DFM. To test it, instead of putting it in Drive but it in manual and click the gear up to 9 and drive around...solves it.

Edited June 23, 2021 by American Cobra

Amcguy1970 · June 23, 2021

Does this only happen to the trailboss or do other non-trailboss trucks also have this engine and issue?

Tyler

Silverado4x4 · June 23, 2021

No it would not be the DFM as DFM is not active when coming to a stop and I believe its only active over 40mph.

It could be the auto start/stop as it will sync engage the starter gear with the 1st solenoid to the fly wheel when under 600rpm then when the engine stops the 2nd solenoid activates to start engine as the gear is already sync to the fly wheel speed. Try turning it off with the switch on the center cluster and see if it still does it as iam not sure if it still syncs the gear with the fly wheel when disabled

Edited June 23, 2021 by Silverado4x4

Rob Mugs · June 24, 2021

6 hours ago, Silverado4x4 said:

No it would not be the DFM as DFM is not active when coming to a stop and I believe its only active over 40mph.

It could be the auto start/stop as it will sync engage the starter gear with the 1st solenoid to the fly wheel when under 600rpm then when the engine stops the 2nd solenoid activates to start engine as the gear is already sync to the fly wheel speed. Try turning it off with the switch on the center cluster and see if it still does it as iam not sure if it still syncs the gear with the fly wheel when disabled

This makes more sense

tadkins522 · June 24, 2021

@American Cobra

I did what you advised to do and it worked. If I disable the DFM I’m assuming that will also work Bc I have a feeling driving around in the low gear 9 is not good for truck?