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Exhaust Brake Issues

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Doug Birch:
We have a 42' 2007 Contessa with a C9 400hp and are having issues with the exhaust brake (Jacobs) holding the coach on 6% or grater down grades. The GCVW is just under 44,000# which is under the GCVWR. I have had Monaco check exhaust brake out and they said everything including back pressure are within spec's. We have tried starting out in 1st gear and it doesn't make a difference, we still have to use the brakes to a point that they start getting hot and you can smell them, seems mainly the front disc brakes. Is anyone else having this issue and have you found a solution for it.

David Rudisill:
I assume that you really did mean that you have an exhaust brake, not an engine compression brake.

We have an '04 Monterey. Previously, we had an '03 Santiam. Both use the Pacbrake exhaust brake.

In neither case will the exhaust brake hold the coach on a 6% grade, and both of these coaches are substantially lighter than your Contessa. You need a real two-speed engine brake to get that kind of engine braking.

On our Monterey, if I use the service brakes periodically to keep the rig from shifting up to fourth gear (around 50 MPH), the exhaust brake does a satisfactory job on 6% grades. Once it shifts into fourth, the engine speed is too low for the exhaust brake to work enough to matter.

Hope that helps.

LEAH DRAPER:
Isn't anybody GEARING DOWN instead of relying on the exhaust brake to do all the work?  If you are not then you have more guts than I,

Richard And Babs Ames:
Most exhaust brakes are programed to down shift the transmission. With the Allison either second or fourth gear without letting the engine over rev. IOW down shift is automatic and the exhaust brake, transmission and engine work together to slow down the coach. If you only go 4th get reprogramed to 2nd gear.

Robert Mathis:
I also have a 42 Contessa and have the same problem. I am taking mine in next week (I hope) to have Cummins look at the settings on the pacbrake. It seems to me that it isn't working as well since they replaced the engine that blew.

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