Jake brake and transmission??

[P7rancher]

We test drove a 2000 CC Magna with Cat C10

One thing I was surprised at was the lack of aggressiveness of the Jake brake. When on high (setting three), the transmission would downshift to 4th and some braking would occur. On setting 1 or 2 I could tell little affect on braking. Your thoughts?

I was told the Cat/Allison could be re-programed to downshift the tranny to 3ed on high, setting three, which would also result in some change in setting 1 and 2. I am trying to read up on Jake brakes and understand the relationship between engine and transmission. Any help??

Finally, the engine has 37,000 miles and they are going to do a valve adjustment and engine service this week. Will the valve adjustment make any difference in how the Jake performs??

Thank you for your help.

Steve

[OneRVer]

Yes you can change your settings. Mine is set for 2nd. gear when the Jake is activated. One thing you might look at, is you valve closing all the way? I had this problem at 26,000 miles and had to replace the valve and valve body. Just a thought.

[1ciderdog]

For clarification are we talking Jake Brake or exhaust brake? Very different devices.
Bob

[P7rancher]

1ciderdog

I understand that the 2000 Magna has a three position Jake brake.


OneRVer, What did it cost to replace the valve and valve body?

Thanks

[RustyJC]

Quote:

Originally Posted by 1ciderdog For clarification are we talking Jake Brake or exhaust brake? Very different devices. Bob

Not to split hairs, but the two different designs are an engine brake and an exhaust brake. Jacobs Vehicle Systems builds both and markets both (yes, including their exhaust brake) under the Jake Brake moniker - the Jacobs exhaust brake for my 2002 Dodge came with a genuine "Jake Brake" Jacobs/MOPAR exhaust brake decal.

I realize that common usage is to interchange the engine brake and Jake Brake terms, but Jacobs does not appear to support such a clear distinction.

Rusty

[OneRVer]

Quote:

Originally Posted by P7rancher 1ciderdog I understand that the 2000 Magna has a three position Jake brake. OneRVer, What did it cost to replace the valve and valve body? Thanks

Seem the total was around $800.00 installed. But that has been 4 years ago and I am lucky to remember what I had for dinner. I do remember that it was cheaper then I expected.

My paper work is in the motor home and the motor home is in the shop getting a new radiator and valve adjustment. When I get it home I will look it up for you and let you know exactly what it cost.