Final Update: 2011/2012 Volvo/Bendix uncontrolled braking issues in cold weather

After having the R-14 valve replaced on our assigned tractor with an updated model, there have been no braking related problems with the truck since.

I think "high roller 302" explained it best in his reply to my original post. I think this needs to be read again:

"This was not an issue normally present on earlier units. We have been seeing only the new units having these "unintended" braking issues (usually in cold climates). The issue is that the TCV is applying brake pressure as if the wheel is slipping. The R14 valve is not then releasing the applied air. Some units have been showing a complete lockup and unable to move. Other units have been showing a brake drag (more dangerous). The issue in not confined to Volvo. Every OEM that uses a bendix system has become affected. The major issue has been noted that if the unit is equipped with an auto trans, the driver would be obvlious to a brake drag issue as the the engine would compensate for the increased load. Burning brakes can be very dangerous. For certain, Bendix has their hands full."