? for the dodge folks.

[scductman]

If you have a 07,08,09 3500 dually 4x4 with 6speed auto and 3.73 gears do you pull in 5th or 6th gear? I was cking the fuel mileage and it gets around 10.5 at 65 mph in 5th but will drop to 10.0 to 10.2 in 6th. If I speed up to around 68 or 69 it gets alittle better in 6th. I think I may be looking for something to wonder about just need to take a longer trip camping. for me 2 or 3 days at myrtle beach don't get it done!! LOL.
Bobby

[DQDick]

Don't have a dually and have an automatic, but I just put it in Tow/Haul and it selects 6th gear most all the time. I'll drop it down as low as third coming down steep mountain grades, but I let it select the rest of the time.

[PackerFan]

I don't have a dually but it is a 3500 (details in signature). I usually pull in 6th gear with the tow/haul on all of the time. I learned on both of my Dodges that they each have a sweet spot that they like to run at. Usually right around 2000 rpm's. My current one gets about 11.5 to 12.5 while pulling the monty. A friend of mine years ago, who drove over the road semi's, told me to watch the tach more than the speedometer when trying to improve your mileage and power. He also added, "Don't lug the engine - Keep the rev's up".

[scductman]

Thats what mine is doing in 6th lugging so the more I drive it the more I will see where it likes to run. My old truck will get better mileage at 73 than any where else. this was the first trip for this one so I will get used to it and see where it likes to run. BTW dick if you can put in a good word to corperate about getting a DQ in pigeon forge Tn I am having issues for like of one there!!!! LOL.
Bobby

[Sierra 117]

I usually tow in 6th gear, with tow haul and exhaust brake on. I will use cruise as well except on a steep hill where I know it will try to maintain speed and downshift hard. In rolling hill country I turn off the exhaust brake and cruise off. Let her roll down the hill, with the aim of accelerating to the speed limit at the bottom of the hill. Then I bleed off speed climbing the hill. I could be wrong but I think this method is more fuel efficient than a constant speed.

[Mynabird]

quote:Originally posted by scductman

Thats what mine is doing in 6th lugging so the more I drive it the more I will see where it likes to run. My old truck will get better mileage at 73 than any where else. this was the first trip for this one so I will get used to it and see where it likes to run. BTW dick if you can put in a good word to corperate about getting a DQ in pigeon forge Tn I am having issues for like of one there!!!! LOL.
Bobby

Just what do ya' mean, Bobby, "my old truck.....was the first trip for this one..."? Did you get a new truck? Or....not?

[steelpony5555]

I tow with mine in Tow/Haul with cruise and yes the sweet spot is around 68-70 mph. Dodge mechcanics will tell you to always put on your exhaust brake even when not towing. Something bout the turbo and keeping the soot from building up in it. Mine purrs down the road at around 1800 rpm....

[scductman]

Mina You and Bob "slung a cravin on me". I ran across a 09 4x4 dually with 34000 miles on it. so now I am trying to sell the old one. I will change my profile and add a pic when I can get my DD to do it she put the last one on for me LOL.
Bobby

[Mynabird]

quote:Originally posted by scductman

Mina You and Bob "slung a cravin on me". I ran across a 09 4x4 dually with 34000 miles on it. so now I am trying to sell the old one. I will change my profile and add a pic when I can get my DD to do it she put the last one on for me LOL.
Bobby

Happy to be of help!!!

PS... Bob says you could give it a good test and come out to Quartzsite next week!

We'll wait!

[Montana Sky]

I get better fuel economy towing 68-70 mph than I do at 55-60 mph towing my assortment of trailers. I put the truck in drive, turn on the exhaust brake and tow/haul mode and let the computer do the rest for me. Empty turning 2000 RPM's equals 82 MPH. My new 2012 Ram DRW seems to be happiest at 1850 rpms or 79 mph.

[Irlpguy]

I drove a '01 Dodge DRW with an aftermarket exhaust brake on it for 11 years, and "never" drove with the brake on unless I wanted the additional assist of the exhaust brake in decelerating. Mine was a standard shift so the brake was either on or off, selectable by a switch on the gearshift.

I now have a 2012 automatic with 3.73 rear end, and don't see the reasoning behind driving with the exhaust brake on all the time, every time you let off on the accelerator the exhaust brake comes on, why loose that hard gained momentum unless you want to slow quickly, or when going down hills.

Steelpony5555 wrote:

quote:
Dodge mechcanics will tell you to always put on your exhaust brake even when not towing. Something bout the turbo and keeping the soot from building up in it.

Not sure I would want those Dodge mechanics working on my rig, I fail to see what the turbo has to do with the exhaust brake, the turbo supplies increased air to the engine for combustion through the turbo boost. The exhaust brake on the other hand is restricting the flow of exhaust gases just beyond the manifold creating back pressure on the cylinders, don’t see how one relates to the other.

One of my best friends is a Dodge mechanic and has been for many years, he does not recommend driving with it on, even though it supposedly won’t hurt anything and you can do that, he sees no advantage unless you are wanting the additional brake assist.

I Would like to hear from those that drive with the brake on as to what their reason for doing it that way is.

The fuel mileage on the new Dodge is crappy compared to what I got on the '01. Guess I have not found the "sweet" spot yet, but I can tell you I won't be pulling my Monty at 70 plus mph down the interstate.

[hutchman]

The 6.7L Cummins uses a Variable Geometry Turbo charger. The sliding vane is used to create back pressure, which acts as a sort of exhaust brake....but not a "Jake" type of brake. The reason you run the brake all the time is to prevent soot build up and eventual binding of the sliding vane.

Here is a link to the Cummins gear selector that, based on your towing requirements, will tell you what they recommend for a towing engine speed. For my combination they recommend about 2100 rpm. I usually tow about 2000 rpm at 60 mph. I just bought a new truck with different gears, so this may change some.

[Irlpguy]

Thank you hutchman for posting, I now understand the big difference between my old add on exhaust brake and it's relationship to the Turbo charger compared to my new VGT equipped Dodge. Since your post I have read a lot of information on the VGT that I would otherwise not have known.

Still not exactly sure how the exhaust brake works now, but I will get that figured out one of these days. It does seem to work well, but in my owners manual it does not suggest driving with it on.

Twas a big jump from the '01 six speed standard to the new six speed auto, keep wanting to shift gears and my left foot keeps coming off the floor...

Oh yes I think the button to engage the brake could have been put on the end of the shift lever rather than on the dash.

By the way your link did not come through in your post.

[scductman]

Hutchman I would love to see that link also. I am going to do some looking to see if I can fine something about it.
Irlpguy I always loved manuals when I was young but now I really don't need one. My 96 was like your 01 it had some help and pulled good but the newer one is sure nice to drive with the 6 speed auto and exhaust brake.
Bobby

[Sierra 117]

With the addition of the bluetec emissions system in 07 and the Cummins 6.7, there were numerous turbo failures due to soot. Since the exhaust brake exercises the turbo, it is believed that using the exhaust brake frequently helps keep the turbo free. There are many examples cited on the Dodge Cummins diesel forum.

[scductman]

Barry I read alot on the dodge forums in the last couple of days and a hole lot of guys say to leave it on also. When the 07.5s came out a good friend that works for the local dodge dealer told me back then that they were having trouble and the cause was people would not use them enough. Back then I didn't think much about it since I didn't own one. Might be something to it so I am gonna run mine alot. JMHO
Bobby

[Sierra 117]

I think you are wise to leave the exhaust brake on, Bobby. The extra fuel costs of doing so will be very little. Also your truck and 5er brakes will last a lot longer.