Manual downshift Allison Tranny

[mobilcastle]

I was wondering if anyone uses the manual downshift with towhaul on your Duramax even though you have an exhaust brake? (2011 and newer duramax). Is there any advantage to using it? My Ford 250 did not have an exhaust brake but did have tow haul-it seemed to downshift quicker than my Chevy does. Thanks for the info.
Steve

 

[hoefler]

While not a Chevy, I have down shifted my Ram's manually all the time with the exhaust brake. No different than down shifting a manual transmission.

 

[kakampers]

We used it once on a gravel downward incline...other than that we've never needed it. The exhaust brake and towhaul works VERY well on the Chevy trucks...

 

[ILH]

I don't use the manual shift on mine. However, I find that in the 'auto' setting, and you feather the brake very lightly, the exhaust brake will engage earlier than if you wait and apply the brake more heavily at the end.

Not sure about Dodge or Ford, on GMC the exhaust brake engages automatically if you have it in cruise control and your speed exceeds setting (assuming you have the brake selected to start with).

 

[danemayer]

I've tried the manual controls but I didn't care for it compared to tow mode with cruise control and exhaust brake. Sometimes I'll skip the cruise control. Cruise on or off, either way works well in tow mode with exhaust brake. Manual control seems kludgy.

 

[kakampers]

"kludgy"...Dan, is that really a word??

 

[danemayer]

"kludgy"...Dan, is that really a word??

Well, since you asked:

NOUN: kludge kluj
(programming) a badly assembled collection of parts hastily assembled to serve some particular purpose (often used to refer to computing systems or software that has been badly put together)

A kludge (or kluge) is a workaround, a quick-and-dirty solution, a clumsy, inelegant, difficult to extend, hard to maintain yet effective and quick solution to a problem, and a rough synonym to the terms "jury rig" or "Jugaad".

My first exposure to the term was around 1970 and at that time it was attributed to John W. Kludge, a Radio and TV executive who had an unconventional way of getting things done. Current references date the term to other origins as far back as the early 1960s.

 

[Bob&Patty]

I have never used the manual downshift even in the old truck without the exhaust brake. The manual downshift really does not work any different than using T/H. It wont engage any lower gear if the brains of the outfit thinks that the engine speed will be too high (RPMs). Yes it will lock it in a gear...but thats all. In fact with the exhaust brake I dont even use the tow/haul anymore.

 

[kakampers]

Well, since you asked:

NOUN: kludge kluj
(programming) a badly assembled collection of parts hastily assembled to serve some particular purpose (often used to refer to computing systems or software that has been badly put together)

A kludge (or kluge) is a workaround, a quick-and-dirty solution, a clumsy, inelegant, difficult to extend, hard to maintain yet effective and quick solution to a problem, and a rough synonym to the terms "jury rig" or "Jugaad".

My first exposure to the term was around 1970 and at that time it was attributed to John W. Kludge, a Radio and TV executive who had an unconventional way of getting things done. Current references date the term to other origins as far back as the early 1960s.

LOL! Learn something new everyday! !

 

[cookie]

Bob, if tow/haul is for accelerating and changes the timing of the torque converter lock-up while towing a heavy load, why would having the exhaust brake change the way you use tow/haul?
Just wondering.
Oh, and why has that "crazy cat" not been traveling yet?

Peace
Dave

 

[2TrakR]

I don't use the manual shift on mine. However, I find that in the 'auto' setting, and you feather the brake very lightly, the exhaust brake will engage earlier than if you wait and apply the brake more heavily at the end.

This exactly. I find just a little actual braking will make the engine braking more aggressive if that's something I'm after.

I have manually set a lower gear for a long downhill grade that was not steep enough to keep it slightly decelerating/hold same speed, but that's really the exception.

 

[olcoon]

About the only time I'll use the manuel shift on my Ram is in the mountains to save the brakes, don't want them to overheat.

 

[Gary521]

In the Silverado, using the manual shift will disable the grade braking function of the transmission. Meaning that it will not downshift to help assist in the slowing process on a grade. In my older Duramax, I had to manually downshift on some steep downgrades to suit me. However, with the exhasut brake function, and sometimes tapping the brake, this is all taken care of. I have tried using the speed control on some mountain passes and it seems to work on the downgrade side but I have not done an extensive test on this. It worked on the Raton Pass heading north. The manual says that the exhaust brake will be more aggressive in the tow/haul mode but I can't see a whole lot of difference using the exhaust brake with or without the tow/haul mode on or off on some down grades. I live in Colorado and find the exhaust brake functrion to be a God Send.

 

[Bob&Patty]

Dave, quick answer. This new Duramax has more HP and torque than I need. Yes I could use T/H but, so far, pulling the heavy work trailer or the 14K Horn. I just does not seem to need to stay in gear longer. This thing is a brute, a 15K loaded trailer....64 MPH....cruise on....still in lock up....up hill....50's XM radio on....auto A/C on....cooled seats on. Dave this thing is heaven. These new GM trucks are QUITE inside. Very little wind rush from outside....very low road noise. GM has stepped up there game and will compete with anybodys truck. Bring u'm on.

Now as to "Baby" the cat. She's 18 now and quite cranky. She will come in the Horn if we are in it....with the door...OPEN. Close the door and its all over for her. She is having nothing to do with being trapped in the Horn. A 126 years old (human years) cat with claws and teeth is something I avoid at all costs.