HarleyD

I think I found my answer on another thread

The "shim" is installed to bring this clearance back to somewhat normal for the clutch brake to travel or compress. A flywheel surfaced that many time is probably best replaced.

Thanks for posting video. I apologise in advance but I have never wrenched.

My old boss always added a "shim"

what was he trying to achieve

He said it made brake last longer

It did "soften"

Triple frame, single axel, disc brakes, auto trans...I am guessing it was specced for a fire tank truck

Thanks I was just looking around and found it, Maxidyne. I was kind of confused because if I run the VIN it says it's a 688 but it's a 690

VIN 1M2B209C1WM0xxxxx

Is this a decent dump truck motor?

I don't think It's the stock motor, truck is a 1998

T2070 Trans

1st time poster, long time follower!

1M1AN09Y8GM022636

Model number cross reference

https://www.macktrucks.com/parts-and-services/support/body-builders/news-and-events/new-mack-model-description-cross-reference-chart/