Exhaust brake?

[Fastcar]

I can feel the exhaust brake come on but get no response from the transmission. As I understand it the trans should downshift as speed is reduced. That isn't happening. Other than that the trans is fine.

Where does it get its signal from? Should I be looking for a blown fuse?

Anybody care to point me in the right direction?

[wlf00]

I have the compression brake on my coach and the exhaust brake may be a little different. But on mine, when I take my foot off of the gas, an indicator light comes on in the instrument panel, the brake lights come on at the rear of the coach, the transmission down shifts, and I can feel the coach start to slow down. If I keep my foot off of the gas, the transmission will keep downshifting until I get somewhere around 10MPH.

What coach do you have?

[Fastcar]

Sorry, it's a 2008 Winnebago 39W with a Cummins

[MaverickBBD]

On my '05 Journey w/ CAT 350 & Alison MH3000 when the exhaust brake is engaged the tranny will indicate 2nd. That means that the exhaust brake is attempting to get the transmission into 2nd. I can watch the computer display (TripTek) and watch as it shifts down to tell me what gear it is presently in. Remember 6th AND 5th are "overdrives". You should go to 4th fairly quickly. If you do need to downshift to 3rd you will definitely know it.

Now for your situation. Call 1.800.FTL. HELP and they can get you started in the right direction. If you don't get through right away, leave a message. They are 100% on their call backs.

Let us know what you come up with.

[ernieh]

Are you the original owner?

The transmission may have been re-programmed like I did mine.

I re-programmed mine to a "null" (ie: nothing happens) with the exhaust brake. That way, I get to choose when and where it shifts.

In my opinion it's much easier to control speed on long grades with my setup.

[Mr_D]

On our 2000 DSDP I had the trans reprogrammmed to preselect 4th rather than 2nd. Wish I'd have left it alone!!
Our present 2002 DSDP I left alone so it preselects 2nd, which is fine with me. Sometimes it's a little too aggressive so I have to add a little throttle.
I also like the fact that if I'm on cruise control and the e-brake comes on it doesn't cancel the cruise.

[dengraham]

Fastcar,
Many of the 2008's were shipped to Winnebago with the compression brake brake "turned off." You need to go to a Cummins place and have them check it. Just tell them to check it and to turn it on. (My friend was missing the wires to make it function.) It was a known issue (but not well adverstised) for the 2008 models. Let us know if this helps.

[Fastcar]

What is happening is the e/b will apply but the transmission will not downshift. At least that is how it seems to function.

[bachler]

Take it to the cat/chassic Manufacturer They will program it. I had ours Reprogramed To were i thought;;;;;; I later had it reprogramed to stock.. It goes itto 2 gear... I would also like to point out. The bast time invested is to go to a allison transmission Seminar;; They will tell you you can be doing 80 MPH. Push the Reverse button the trans, says No I will not do that;; Life is good;; That transmission with a bit of tweaking can take up to.. Get this, 9000 HP; Unbelieve able;;

[RickO]

I'll second the suggestion to call 1-800 Ftl Help. Those guys are great to work with.

Good luck and keep us posted.

Rick

[Fastcar]

Thanks all,

Have a appointment in Gaffney in a couple of weeks. Will get it addressed there.

[ernieh]

FWIW, When I had mine re-programmed, Freightliner said that they could not do it. I had to take it to an Allison shop. The good news is that they did not charge to make the change.

[Fastcar]

Quote:

Originally Posted by ernieh FWIW, When I had mine re-programmed, Freightliner said that they could not do it. I had to take it to an Allison shop. The good news is that they did not charge to make the change.

That's what I just found out over the phone. Seems the tech's at Gaffney are not Allison or Cummins certified and as such can't do a reflash. I believe it has to do with proprietary software or some such. I may get lucky and it might just be a electrical issue. Then again with the carbon and stuff it may have messed up the slide on the VGT