PacBraKE

Brett, didn't you say the same thing I said, except maybe a little more detailed???? Duh, or were you answering the original poster's question, not responding to my response?

Thanks for all of the advice, just some more information as to why the PacBrake set up. I bought this coach in 2008 but it was a left over model that sat in San Diego for a year after being driven from Indiana. I am thinking the people who drove it from the factory might not have used the engine brake. I am thinking that was the main cause plus the lack of lubrication. I tried to buy the PacBrake lubricant locally at Freighliner or my local parts store didn't have it. It's available on E-bay;)

John & Angela wrote:
On ours turning the key from off to on (not start) "fires" the pac brake once. On and off, very quick. Don't know if its part of a self test or not.

That's interesting! I'll try that tomorrow.

On ours turning the key from off to on (not start) "fires" the pac brake once. On and off, very quick. Don't know if its part of a self test or not.

"tinkerer".....Your PacBrake can only be tested for operation while driving. Typically, they don't operate under about 20 mph.

Do you have a turbo boost gauge on your coach? If you do, the boost gauge will go to zero if the exhaust brake flapper is closing. If it doesn't close you'll still see some boost.

On my previous coach, 2005 Monaco Diplomat, the PacBrake never worked from new. I removed an engine cover and set up a video camera. I took it for a test drive and videotaped the arm on the PacBrake. You could also have someone just watch it, my wife wouldn't do it.

NO, that will not test your exhaust brake.

Drive the coach. Down arrow to 3rd or 4th gear. Accelerate to the higher RPM range for your engine. Turn on/off/on the exhaust brake. Since the transmission remains in the same gear, you have eliminated it as a cause of additional braking.

You should feel a real difference in braking with the exhaust brake on.

BTW, the Allison ECM is the first place your exhaust brake signal goes, causing your transmission to begin downshifting toward the pre-select gear. So, if your transmission window does not change from "6" to what ever your pre-select gear is (2nd and 4th being common choices), the brake is not working electrically.

I make an effort to use our pac brake every time I take the motorhome out to prevent it from seizing up. What I do is apply the Pac brake. You can feel the transmission downshift, and engine braking occurs. When the RPM gets down to 2000 rpm or a little higher, I turn the brake off. Hopefully the transmission won't upshift. But when I turn it off, I can feel the braking let up some as the Pac brake releases.

Ed Headington