Jake Brake Programming

[cmillsap]

Most Jakes on new Wanderlodge(s) were programmed at the factory to select 4th gear initially and then progressively select 3rd then 2nd and then deactivate when travel speed dropped below 15 mph.

Many owners disliked that programming as it removed the Jake’s ability to function above a travel speed so fast that 4th gear would over rev the engine. Consequently, they had their Jake Brake re-programmed to select 5th gear first then progressively shift to the next lower gear as travel speeds decreased to allow downshifting the transmission without over revving the engine.

My previous LXi’s Jake Brake was set at the factory and was never changed. A travel speed over 65 mph locked out the Jake until travel speeds were reduced below that point. So, I made it a practice to stay below 60 mph on downgrades to prevent having to over use the chassis brakes to slow the bus down.

Most Wanderlodges were equipped with a 2 or 3 stage Jake. Both LXi(s) I have owned were equipped with a 3 stage Jake. This makes it great for selecting the perfect stage for the downgrade that would allow the Jake to hold the bus at a constant speed. By manipulating the Jake’s stage, I could travel the length of the downgrade without ever touching the chassis brakes.

Now I find that I, evidentially, have a hybrid program on my present (new to me) LXi. The Jake is programmed to select 4th gear initially but to my surprise the transmission shifts to 5th gear initially if my travel speed is too high for the Jake to shift the transmission directly to 4th gear. I use a Silverleaf engine monitoring system that displays the selected gear and the actual gear. The Jake selected gear displays a 4th gear but the actual gear shifts to 5th until travel speed is reduced to allow shifting to 4th and so on.

This program is the best of both worlds. It allows the Jake to activate at a higher speed which is helpful if I’m traveling at a higher speed than 65 rather than waiting for the speed to be reduced enough to initially shift to 4th gear. On the other hand, if I’m traveling below 65 mph, I get the benefit of faster reduction of speed when the Jake immediately shifts to 4th gear rather than it having to select 5th first before selecting 4th.

Does anyone else have a Jake Brake programmed this way?