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MDTdriver
12-07-2005, 09:57 PM
When I bought my 4700 the salesman? 8) said If the cruise control was on then the exhaust brake will not go on? :( Well I tested it this summer on the way back from Wi. to Ca. set cruise start down hill turn on exhaust brake and the truck holds cruise speed down 6% grade. :lol: Question does this work on any one else's MDT :?:
Larry & Kathy

Motor31
12-07-2005, 11:24 PM
My Volvo works on cruise control. After it accelerates about 4 MPH the jake cuts in.

Jerry
12-16-2005, 08:48 PM
It all depends on how the computer parameters are programmed. On my 4700, if I am running on cruise control and activate the exhaust brake, it cuts the cruise off. Once I get to the bottom of the grade I have to hit the 'Resume' button to reactivate it.

Jerry

MDTdriver
02-21-2006, 11:06 PM
I am glad mine is programed for braking and cruise. It works very well going down hill on a 4% grade. On more than that I turn off the the cruise and brake to 40mph and exhaust brake will hold for ever going down hill.

Larry & Kathy plus Mojo

Stripit
03-18-2006, 09:05 AM
I am glad mine is programed for braking and cruise. It works very well going down hill on a 4% grade. On more than that I turn off the the cruise and brake to 40mph and exhaust brake will hold for ever going down hill.
Larry & Kathy plus Mojo
Do you have the 6 speed? and what gear does it down shift into when the exhaust brake kicks in? Mine was going from 6th to 2nd, and I just had it changed to 4th gear. I find it doesn't hold me back like the 2nd gear did, causing me to use the brakes more. And, it does allow the truck to gain speed going down steep grades???I manually down shift to 3rd as I need it. How about you?? I'm towing 17,000 lbs.

MDTdriver
03-19-2006, 10:05 PM
Yes I do have the 6 speed. exhaust brake is set at 2 gear, I have been told to change to 4 gear by people with MDT's for a lot of years. And also told I then could down shif to 3 or 2 gear for exhaust braking. But I do like the 2 gear works for well in city traffic and slow speed on freeway's.
And it does work very well on 4 to 6% grades when I slow down to 45 to 50 the brake will start in 4th then down to 3 and hold speed at 45 all the way down. On city streets below 50 when I let off the pedal 4th 3d 2d and 1st. then we are at a 5 to 9 mph.
I vote of using 2 gear for the exhaust brake progam.

Larry & Kathy plus Mojo

Stripit
04-07-2006, 08:30 AM
double post

Stripit
04-07-2006, 08:30 AM
Well, I had mine changed about 2 months ago at the Allision dealership. They hooked up a computer unit and in about 90 seconds it was complete and we went off for a test ride. I've had a chance now to drive about 3,000 towing miles and I think it was a well worth investment. It doesn't have the neck snap shift down to 2 like it did, and the rpm seems much more controllable heading down a steep grade. I still can push the selector button to shift farther down when needed, and the rpm's are not way up there when coming over the crest of a steep downgrade. I like the change and should have done it years ago.


Yes I do have the 6 speed. exhaust brake is set at 2 gear, I have been told to change to 4 gear by people with MDT's for a lot of years. And also told I then could down shif to 3 or 2 gear for exhaust braking. But I do like the 2 gear works for well in city traffic and slow speed on freeway's.
And it does work very well on 4 to 6% grades when I slow down to 45 to 50 the brake will start in 4th then down to 3 and hold speed at 45 all the way down. On city streets below 50 when I let off the pedal 4th 3d 2d and 1st. then we are at a 5 to 9 mph.
I vote of using 2 gear for the exhaust brake progam.

Larry & Kathy plus Mojo

MDTdriver
04-07-2006, 04:56 PM
I seldom drive over 58mph when pulling my 5er.
At 50 to 55 the brake will come on and trans will go to 4th and I brake to 45 or 50 and trans goes to 3rd and if it is a 6% grade it will hold 3rd at about 45mph, if I touch the brake pedal it will drop to 2nd and slow to 35 to 40, this is great at speeds below 50mph or city streets.
At freeway speeds I just brake to 50 and Jake does the rest.
I do watch the speedo shifts points and do not turn off brake near shift points. This makes for smother transitions of engin and trans.

Larry & Katny plus Mojo

glav
05-30-2006, 10:58 AM
Stripit (Stacey), what did it cost to re-program the tranny?

davidandrew
09-26-2013, 08:06 AM
Yes, my truck also work cruise control.

MDTdriver
09-26-2013, 07:54 PM
I have not been on the forum for a few years nice to see a new post I was sent a email by 5thwheelforum when you posted. I an still driving my 4700 7 years later great trucks, year 2000 and still runs like new. Good luck on your travels.

Rena
07-04-2018, 11:14 PM
If I don't have a Jak break, will my Prodigy trailer break and Tow Haul downgrade the transmission to help control my speed going down a 6% grade?

Stripit
07-05-2018, 09:29 AM
If I don't have a Jak break, will my Prodigy trailer break and Tow Haul downgrade the transmission to help control my speed going down a 6% grade?

You are answering a really old post, but the Prodigy won't apply the brakes unless you apply the truck brakes, but the tow haul mode will use the transmission to slow you down. Tapping the brake pedal once will shift the trans into a lower gear, depending on the program you have in your vehicle it could kick down two or more gears to help slow you down without pushing any more on the brake pedal. On my V-10 that is how it works and it works well in slowing you down.

Rena
07-07-2018, 02:31 PM
Thanks. The Tow Haul worked great. I appreciate your help.