To do or Not to do

[jerichorick]

Originally Posted by scooterbob

When driving under normal driving conditions, how many people leave the exhaust brake on ?

ALWAYS!!!!!

[Hit_the_Rhod]

Originally Posted by noserider

I leave mine off and just switch it on when needed. My approach to driving is to make everything shift and brake smoothly during highway type driving. While I use it often, there are times in stop and go traffic and others where leaving it on results in additional shifting that seems more of a nuisance than a necessity. Try it both ways and see how your rig behaves. I think the answer will come naturally to how you like the rig to respond under varying road and traffic conditions. To be clear, I leave it on all the time while climbing and descending big grades.

That is exactly what I do with mine!

[Mr_D]

Originally Posted by mel s

Apparently you have a a "compression release engine brake", (aka: "Jake brake")...not an "exhust brake"?

Which, for this discussion, doesn't matter.

[Pusherman]

Originally Posted by mel s

bobmac

On most, (all?), Caterpillar powered coaches the Exhaust Brake Mode in the Cruise Control Perimeters of the ECU can be electronically programed to "Coast", (rather than "Manual or "Latch")...which results in the same exhust brake action you describe.

BTW, in 2011 Fabco Cat, (now Fabick Cat), in Weston, Wisconsin programmed mine to "Coast" at no charge.

Mel
'96 Safari. 148k miles

What Mel said.

I leave my exhaust brake on all the time. I too have it programmed to 'Latch' mode, which CAT did for me for no charge years ago.

Here's how it works:

With the exhaust brake on, and cruise on (but not engaged) the exhaust brake will only activate if you step on the brake, or turn the cruise off. This way you can coast w/o the exhaust brake activating.

With the cruise off, the exhaust brake will activate if you take your foot off the accelerator.

For me, this has become second nature, as I now activate the exhaust brake via the cruise switch which is on my turn signal switch. If I want to engage the exhaust brake, I turn the cruise switch off, or hit the brake pedal. If I want to coast, such as coming off an exit ramp w/o actuating the exhaust brake, I switch cruise off, feather the accelerator pedal, and turn the cruise switch back on without activating it. Sounds complicated, but it's not.

This way I have the added braking at hand w/o reaching to activate the master switch simply by either touching the brake pedal or turning the cruise off. Works for me.

Another benefit of this programming with the exhaust brake ON and when in cruise, the exhaust brake will activate when your speed climbs above 5 or 7 mph (this metric is programmable also - I changed mine to 5 mph) keeping you from running away down an incline. Don't have to touch the brakes or activate the exhaust brake switch or anything. I love the intelligence of the Allison transmission!

P.S. The second part of this discussion is that I had Allison reprogram the transmission downshift to '4' vs. '2' so when the exhaust brake does activate, it downshifts from '6' to '4', as I always found downshifting to '2' with the exhaust brake was way too aggressive when coming off an exit ramp, or even coming into traffic. If I need more exhaust braking going down a steep grade, I manually downshift the transmission to '3' or '2' as needed.

With these 3 programming changes, I found the driveability of the coach has been greatly improved when needing to slow the beast down in all situations.

[XBoater]

I run with the brake on most of the time and will shut if off from if needed. It is an important part of slowing down and I don't want to be without it should an emergency stop be needed. I do drive defensively so generally it works well to slow me down and there is no need to apply the brakes, doing the job it was intended for.

I will turn it off when running in traffic or on a long approach to a traffic light to allow me to coast. It also works well with the cruise control and allows coasting up to 10 mph over the set speed.

[poppopc]

Turn on when needed. With the cruise on the exhaust brake does not engage.

[palehorse89]

Originally Posted by poppopc

Turn on when needed. With the cruise on the exhaust brake does not engage.

I had mine re-programed, now my engine brake maintains the cruise control set point. 3 MPH over/under on/off, works wonderful
My switch is always on.......

[Road_King]

Originally Posted by noserider

I leave mine off and just switch it on when needed. My approach to driving is to make everything shift and brake smoothly during highway type driving. While I use it often, there are times in stop and go traffic and others where leaving it on results in additional shifting that seems more of a nuisance than a necessity. Try it both ways and see how your rig behaves. I think the answer will come naturally to how you like the rig to respond under varying road and traffic conditions. To be clear, I leave it on all the time while climbing and descending big grades.

...all the above. Just consider the traffic conditions and adjust as necessary.

~George

[Terry L T]

Mine is programed so the cruise won't work unless the pac brake is off. So, while cruising down the hwy with the cruise on and I want the pac brake to work, I hit the switch that turns on the pac brake and it turns off the cruise control. I hope the '03 Cummins can be reprogramed and I also need to turn off the brake light when the pac brake comes on. I did not know this was available until I read this "thread" thanks everyone.

[jerichorick]

I didn't realize there were so many different flavors of engine breaking. Both of my Winnebago products work basically the same. No breaking on coast. Breaking if free accelerating.

My '05 400 ISL had a 2 stage fuel cutoff breaking. I like how that worked, especially in the mountains. This '11 has the exhaust break. It is not as aggressive but it does the job. I always have it on. Saves wear and tear on the service breaks. The SMI to the towed only works when I apply the service break.

IE: Keep it on if it works like mine. Not a nuance and doesn't cause erroneous shifting.

Rick Y

[LJowdy]

ON my previous coach, (Rexall Roseair) I had a pac brake with an on and off switch. I changed it to a foot switch and that was the best thing I did to that coach.

Current coach has a Jake and for most of the time I leave it off. If needed, I set it to 3 cylinders and that's usually enough to make a difference