No, your just lucky. The Vacuum pump runs 100% of the time the engine is running. Except when we have Ice or snow, my Jake is armed all the time. Sure helps extend the life of the service brakes.

8Valve

 

Sometime in the near future, I'm going to be installing a Jake on my 06 which is an automatic.

I just looked at the link on page one which had the install instructions and saw the can used to produce the vacuum. That can looks just like the ones GM used on the 5.7, 6.2, and 6.5 diesels. Those would run well over 150k without a failure. The pumps were driven off the camshaft just like a gasser
distributor was. All it was, was a cam lobe that pushed on a metal plate in the center of a rubber diaphram in the can.

The vacuum pump on my 2000 Dodge Cummins that drove the Jake was part of the power steering pump on the same shaft on the other side of the plate.
That had 203,000 on it when I sold it with the Jake working fine.

It appears to me that either the thickness of the rubber diaphram that creates the vacuum is failing or the striker plate is tearing away from the
rubber caused by to much contact or to long of a stroke off the drive. The speed off the pulley could also be excessive possibly needing a larger pulley.

I'm going to check the pulley size on my old truck and see what the differance is with the pulley in the kit. I wonder if the old style power steering pump with the vacumme pump could be installed. ?

Dave

 

I can't find anywhere near here with any in stock, and would take up to three weeks to get one in, Has anyone got an online source for the Cummins part.
I get a bonus in March, and I will be replacing the exhaust brake with a BD pump at that time. If I find a vacuum pump it will probably fail about then. But I need to find a pump, as the truck ain't safe with the trailer, without it.

 

My truck has 106525 miles on it, with the original brake pads, very little wear. Original tires as well, with legal tread all round. The jake has certainly helped a lot - even with the trailer, it holds the rig back on steep hills.

 

do you have any info to back this up. my dealer voided my warranty because i have a pac brake on my truck.