M923 parking brake spring brake issue

[chadande]

The parking brake on my truck is not releasing the spring brakes when disengaged. I need to use the spring brake override on the dash in order to move the truck. The drivetrain parking brake works as it should. I can't find a troubleshooting guide in the TMs that cover the air part of the parking brake. The lever with the wheel moves as it should on the parking brake handle. Any help would be appreciated. Thanks!!

 

[M35A2-AZ]

You can down load the P2P s/w here on SS in the TM files. It will help a lot in trouble shooting
Are you sure it is just the spring brakes that are releasing?
Also does it work, then as you drive and use the brakes does the brakes start to drag and then lock?
If so make sure the ball valve (if it has one) on the front service side is open and the vent on the glad hand
cover is clear.
The front service side must vent.

 

[chadande]

Hmm, I'll have to check when I get home but I'm almost sure both front glad hand covers are on tight.

 

[M35A2-AZ]

Hmm, I'll have to check when I get home but I'm almost sure both front glad hand covers are on tight.

The glad hand cover on the service side should have a vent on it like the axles have on them. Also if the service side has a ball valve it should be open.

 

[chadande]

I think that was it. Glad hand cover was on, but no vent that I could see. It operates like it should now, thanks! I'll have to fabricate a vent of some sort so the cover isn't just dangling.

 

[Csm Davis]

I can send you the correct cover

 

[M35A2-AZ]

I think that was it. Glad hand cover was on, but no vent that I could see. It operates like it should now, thanks! I'll have to fabricate a vent of some sort so the cover isn't just dangling.

Glad that fixed your problem!!!!