PacBrake issue

palebluedot

Active Member
This is just a heads-up to anyone who has a PacBrake PRXB exhaust brake on their truck. I had mine installed July 08 by Camping World in Alabama. The unit has an electric air compressor which was mounted on a cross member under the truck bed in front of the rear axle. It would occasionally blow the 30 amp fuse in the line running from the truck battery to the compressor motor. This week the exhaust brake just completely quit. On examination, the compressor motor would turn a few RPM when tapped with a large bolt and then stop. It acted as if it was trying to sieze up. I removed the compressor unit from the truck and placed it on the work bench and removed the bolts securing the motor housing. When I loosened the housing a small amount of water drained from the unit. After removing the housing from the armature, the whole inside of the motor was covered with rust and the brushes were corroded. PacBrake tech support says the motor unit is not sealed (waterproof) and suggested relocating the compressor unit. If you have one of these units mounted beneath the truck, it would be worth checking it out. Mine lasted just over a year. PacBrake is sending me a new compressor at no cost even though it is out of warranty a couple months.
 

dieselengineer

Charter Member
Have my compressor unit up as high as possible under the hood. Cooled by the fan with the air inlet remote mount in the cool air stream in front of the radiator. The E brake works great. Not had a problem with many years of services. Always use the pacbrake lube not WD40.
 

MurrayN.

Well-known member
The shop that installed my PacBrake put it under the hood of my Duramax where it would work great until you got a good hot summer day and pulled up a good hill, then the heat under the hood would cause the thermal overload to kick out and you would have no exhaust brake!:eek: So I would get up the hill but when I started going down and needed it, it would not be there. It was mounted right on the driver's fender. So what I did was relocate it to under my driver's door on the outside of the frame. I took a piece of mudflap and made a big 'L' shape to protect it from the front and bottom. It works like a charm now and has never failed me since. I absolutely love it and would never go through the mountains again without it on my truck. It takes all the stress out of those long downgrades.
 

sidney dreyfus

Well-known member
Jim,
My PacBrake dealer installed our air inlet remote on the back firewall in the engine compartment. Most of the time it works great. The PacBrake compressor has cut out on occassion when it became too hot. I need to relocate the remote inlet behind the fan like yours. How did you mount it behind the fan? Do you have a close up picture? What kind of hardware did you use to mount it?
 

dieselengineer

Charter Member
Sidney
The location for the inlet as you stated is the std location shown in the install docs. If you remove the metal washer, the plastic intake filter housing comes off and can be moved to the front. I located my on the drivers side next to the intercooler so fresh cool air that enters the grill will be used by the compressor. You will need to lengthen the tubing. The original compressor mount was unable to be used, since I have the banks high ram. So I custom mounted it in front of the engine so air from the fan would discharge over the unit for cooling. Works great, doesn't cutout. Also mounted a clutch switch so the brake does not operate during a gear shift.
 

palebluedot

Active Member
Hello When it works does it work good?
The PacBrake PRXB is without a doubt the best accessory money I have spent. We installed it a few months before a 12 state/9000 mile trip from Mississippi through the southwest and up to Montana. I could lose speed down an 8% grade with the 3610RE in tow. The automatics with tow/haul in the new trucks seem to work fine, but I can tell you, in the mountains this thing is WONDERFUL. On level ground approaching a red light or stop sign I never apply the service brakes until the final few feet to come to a complete stop.
 
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