Need Dodge exhaust brake 101, please.

[sreigle]

OK, we bought this new Dodge. We won't actually take delivery until late this coming week but I brought the manuals home to start digesting them.

The truck has the factory exhaust brake, operated by a button (with small pilot light) on the dash. I was kinda hoping the manual would provide some how-to and when-to rather than just informing me it's there. For crying out loud, this owners manual almost requires two hands to carry. It has 541 numbered pages. But about all I can find about the exhaust brake is that it is there and it is turned on and off by that button.

Would some of you mind enlightening me? What do I need to know? Do I turn it on only when going downhill? Only when going downhill and already gaining speed? Only when towing downhill and gaining speed? Or do I turn it on when towing and leave it on the entire trip? By now you know I am purely an exhaust brake newbie. Any and all information is appreciated.

Thanks.

[hookman]

Turn it on at the start and leave it on when you let off the fuel it will help slow you down. It is better to use it all the time. This will stop the brake from carboning up and you will get better mileage out of your brake linings.

[RC and Samantha]

I don't know the answer but I loved driving my sister's on the way to Florida pulling the horse fiver. I also liked driving it when not towing. Now PLEASE don't tell Dick that I said that!

Congratulations on the new truck, I'm sure you both going to love it.

Patty

[ols1932]

Steve,
If it works like mine, you won't be able to operate in cruise with the brake turned on. On my Ford, I use it all the time when not able to use cruise (up and down hill). But it sure works well in slowing me down and helps hold the speed down when going down hill.

Hope this helps, even if it isn't about Dodge.

Orv

[boylanag]

Congratulations on your new truck. When you drove out as we were getting ready to leave Camp Keystone the other day, we thought that the dealership had come through for you.

[H. John Kohl]

Steve,
I have the Jacobs (Dodge warranted) exhaust break on my 03 Ram. The short answer is what Hookman told you. Turn it on and use it. My exhaust Break( EB) will work with the cruise control. I normally turn it on and leave it on even when I am not towing. It helps reduce the wear on the breaks and since it is functioning most of the time it does not carbon up or stick.

side note: (When I had the truck inspected this year the mechanic commented on the new tires. Yep just 5K on them. After the inspection he said "NEW BRAKES too?" Nope original brakes. He said, "Lots of wear left on them." That was with 50K on the truck.

Operation,
The exhaust break is a butterfly valve (like a choke) that blocks the exhaust when activated. It is either fully open or fully closed. In the closed position it restricts the exhaust function (exhaust stroke) and puts resistance on the engine. Since it puts resistance on the engine it will not operate if there is any positive fuel flow (meaning you foot has to be off the accelerator).
Now you have the auto and I have the manual so I can only explain how my manual works.
When going down a steep hill I use the rule, "you go down the hill in the same gear and at the same speed as you pulled the hill." Those hills in Western Maryland are a 4th gear 45 MPH hill for me. So when I am at the top and ready to descend I down shift to 4th with the EB on, set the cruise at 45 and let the machinery do it's thing. Note: The higher the RPM the better the EB works so my down shifting helps to keep the RPM higher. I do a modified double clutch. (Push in the clutch, shift to neutral, tap the throttle and then shift into the lower gear.) The EB does switch off when I tap the throttle but comes right back on once the computer confirms there is no fuel flow.
I do not know if your automatic will automatically down shift when breaking or not. You will have to let us know.
I can use mine on a cold morning to help warm up the engine.
When the EB is on there is a hissing or gravel sound. If it is annoying in the city they I turn it off.
I hope this helps.
Good luck and safe towing.

[sreigle]

Thanks to all of you. Exactly what I wanted to know. I'm anxious to get a change to actually try it out. I'll have to check to see if there's a setting on the computer to make the exhaust brake default to on and not have to push the button with each startup.

John, the manual says breaking while in tow/haul may induce transmission downshifting but I've not actually tried it. Plus, it has ERS, "electronic range selection" which is a +/- switch on the gearshift lever that allows me to manually shift down or up.

It also says to put 500 miles on the engine before towing a trailer. No problem. We'll be able to do that. But it also says to not exceed 50 mph for the first 500 miles of trailer towing. I don't see how that's going to be possible unless we stick to interstates. So I guess I'll just keep it to 55 to 65, varying the speed every now and then. Our route on US highways will provide plenty of speed variation but we likely cannot hold to 50 mph without becoming a traffic hazard.

Thanks again to all for the expert help.

[simonsrf]

Steve and Vicki,

Congratulations on buying a ‘real’ truck!

I also have a 2006 Dodge Cummins diesel with the Jacobs engine brake installed. Years ago, I used a Jacobs engine brake on big rigs, and when I started using the one on this truck it was pretty much the same, except the automatic transmission and the cruise control may complicate things a bit.

First, you can use the brake with the cruise control. I use it this way and it makes driving a real pleasure. On FLAT freeways and small downgrades, I don’t use the ‘Jake’, because I like to get the occasional ‘float’ that gives me a bit more fuel mileage, when there is no chance of runaway speeds. Remember, you can turn the Jake on or off at any time. I always use it on the downgrades, but remember that you can give it fuel and the Jake disengages until you take your foot off the accelerator, so you can keep your momentum to make it up the next hill.

I use the Jake also when the trailer is not attached. When driving around town, the Jake lessens the need to use your truck brakes. Just like John, I turn it off while stopped in town or when the throttle is not engaged. It takes a little practice to get used to the short delay, but in a very short time, you will be using it like a pro.

On downgrades, I recommend you use the same gear going down that you would use going up, watch your RPM’s and you can judge the effectiveness of the Jake. On steeper downgrades, the Jake just won’t hold the truck and trailer back, so a little truck brake pressure on the pedal will usually slow everything down and the truck should at the right speed shift down to the appropriate gear, but the RPM will increase, so watch your speed; the Jake makes keeping the RPM’s down, easy!

This is a real hard thing to describe, and I apologize for the rambling, you just have to play with it, you can’t hurt a thing by having it on or off.

Hope this helps, you can always PM me for any other questions you may have.

[sreigle]

Thanks, Robbie. I appreciate all the helpful info in the "rambling." As I go through the manual I'm making lists of things to check on, things to try out, and things to change (computer settings). Normally I'd just go sit in the truck and go through the manual but can't do that yet.

[c5racer]

I have the exhaust brake with the 6 speed manual and if I want to go down any hill at say 45 mph I just put it in the right gear that will keep the rpms at about 2500 to 3000 rpms and set the cruise for 45 mph and enjoy the ride. The exhaust brake will kick in and out and hold the speed at 45 mph. You have the new American made 6 speed auto so you should be able to find the right gear for going downhill at the speed you want to. I haven't found a hill that required me to use the brakes yet. I think that is because of the 6 gears and knowing what rpms the motor runs in each gear, just don't over rev the Cummins.

[sreigle]

Thanks Pete.

[Hemlockusa]

Steve congrads on the NEW DODGE.. The restrictions on TOW SPEED the first 500 miles - There is a reason for this. Breaking in the rear end gears, don't let anyone kid you. That is important. Christa and I towed from Topeka, to Amana Colonies (Octoberfest) Iowa, a few weeks after we bought our 2005, 3500 Dually. That was the longest 500 miles I believe I ever spend towning. we were on interstate so there was no problem with folk's passing us. I did get some looks probably as to why I was driving so slow. OH, as the 500 miles ticked over the Cummins CAME ALIVE and it hasn't looked back. ho ho ho When you getting back to Kansas and KC. WE MISSED YOU BOTH AT BRANSON, but you haved another chance next May

Later my friend John

[sreigle]

Thanks, John. Was that 500 of towing after putting the first 500 on it?

[JimF]

So that's where you guys were when we left Keystone, sorry we didn't get to say goodbye but the reason is clear, you have a new Cummings wrapped in a Dodge. Hope your service is as good as ours has been. It was really nice meeting you folks and all the other MOC'ers and the other friends we made. Hope to see you in September.

Jim and Joan

[sreigle]

Sorry we missed you when you left, Jim and Joan. It sure was a pleasant surprise to see you sitting out there.

[BigAl52]

Steve
Just curious what made you go with a Dodge rather than another Ford. From reading most of your posts I thought you would have gone with another Ford. Also is the shorter box on the mega cab going to present any clearance problems in turning your trailer. I also have a Dodge with the short box but I believe the mega cab box maybe a little shorter than mine. Congrats. Al

[sreigle]

Last question first, Al. I found out the megacab shortbed is identical to that on the quadcab. Six feet 4 inches. Or 5 inches shorter than my Ford shortbed and 2 inches shorter than the GMC's (I think GM calls it the standard bed). That concerned me so I took a tape measure to it. For me, the critical measurement is from cab to axle, which is where the hitchpin center will locate. It's just one inch shorter than my Ford. The other four inches is behind the axle. That only matters if you plan to carry cargo back there very often and I don't.

As far as why Dodge over Ford. Well, that was a very tough decision. I waffled back and forth for several days. One day it was Ford; another day it was Dodge. And even when signing the papers I wondered if I was making the right decision.

I really liked the Ford a lot. I drove all three major brands. The Dodge was the strongest engine. Obviously this is solo since tow testing is not allowed. The Duramax was a distant second with the Ford slightly behind that.

The Ford had the best ride. That new rear suspension made a difference in my estimation. The GMC was not far behind. The Dodge was better than older Dodges I've driven but was the firmest of the rides. (I'm planning to go to the Rancho 9000S adjustable shocks with compressor and incab controls to remedy that). But the ride of the Dodge was really not bad. Just a bit more truck like.

The Ford Lariat was the more luxurious. The Dodge Laramie H is luxurious enough but doesn't have the little touches of the others. Still it's pretty darn nice.

Now to the nitty gritty. First, I want this truck to last a very long time. We put a lot of miles on our truck every year. The Cummins has the reliability/longevity reputation. The Ford 6.4 is looking to be a good one but it's still very early and that was a major factor for me.

Add to that - Dodge has $3500 cashback on the 2007 2500/3500 until July 2nd. Also, I have the xplan for all three mfrs and Dodge's is a better break than the others. Ford is second, GM third.

When I added everything up, it came up Dodge. If this were a year from now when the 6.4 is more a known quantity, it may well have been Ford. I just hope I made a good decision and I think I did make the decision that is best for our situation. I hope so, anyhow.

[Charlie]

Your decision for the Dodge maybe correct as far as the reliability of the engine. I was faced with the same choice when Ford was talking about the 6.0 and doing away with the 7.3. I opted to not wait and go with the proven engine and have not regretted that decision. Hopefully Ford does not experience with the 6.4 the problems it had with the 6.0. This does not help the company from a customer viewpoint.

Congrats on the new truck and think that you will be happy with your decision. If I was in your shoes I would have probably made the same choice.

[skypilot]

Steve: I've got the 06 3500 DRW with Auto and exhaust Brake -- test drove a new 07.5 with 6speed auto this past saturday -- NICE!! Congrats on your new rig. Now to the questions at hand -- as you've noticed from several posts, we need to keep our RPMs up to make the exhaust brake work at its best. For you that should be easier as the + - function will allow you to 'shift' to a lower gear easier than I can. Watch your top RPMs though - don't want to over rev the engine!! Your transmission will downshift for you as you slow down and then exhaust brake will go off when it shifts, then come back on automatically. Really nice and comfortable -- in or out of Tow/Haul mode. For normal - on the road use - you will have to force the downshift when going down hills -- this is where I think you'll have the advantage over the older 48RE transmission -- I have to drop mine from D to 2nd and I don't feel comfortable doing that; wish I had the manual 6 speed at times like that. Assuming the dealer sales droid told me correctly, as you crest a hill, click the down (-) button to 4 on your panel -- if you are in 5th (overdrive) it will force you into 4th; button to 3 and you'll be forced to 3rd (once your RPMs drop enough to allow that gear). Now as you slow down you will downshift automatically to 2nd and ultimately to 1st. Upon pulling out from a stop you will upshift to 2nd, and then to 3rd (or 4th) but no higher. Whatever gear you have manually selected becomes your top gear until you select a higher gear using using the plus (+) key. Hope that made sense. Very much like the Allison transmission for those who have such. On my 40 mile test drive it seemed to work as he told me but I was not pulling anything and no long hills to test it on, just short length ones.

As for the 500 towing break-in; this is mainly for the differential gears. They need to seat properly and temper (as my dealer called it); the differential gets really warm when towing. I had to have my rear Diff fluid changed at 10K miles -- was done by the dealer under warranty as it looked weird (was cloudy). When they pulled the cover to drain it, nothing out of the norm found on the gears but you could see where the gears intertwined -- and the tech made a point to show it to me since I also asked about the 500 towing miles at 50mph or less.

Once again, I'm wordy but hope I helped.

[sreigle]

Thanks, Skypilot. That's pretty much the way I understand it, too, except the manual says when in tow/haul I can apply brake and get it to downshift that way. Since I'm used to the Ford auto downshifting when in tow/haul on a downgrade and also when pushing the brake, I'll probably use that method until I get used to the manual switch. I also read that when I want to go back to Drive to allow the transmission to decide the top gear I can just hold the + key and as it goes up through the top gear selection, after 6 it will go back to Drive. I tried that a couple of times and it worked.

We finally take delivery late Wednesday. Today and tomorrow it's getting the rhino liner, the chrom tubular steps, bed rail caps, and the hitch and toolbox installed.

When we leave Saturday it's a bit over 600 miles to our next destination. We'll be on mostly US and State highways so I'm not sure I can hold it to 50 without being a traffic hazard. I may end up running 50 when I can and speed up to 55 to 60 when I can't. Since I need to vary the speed and also will be slowing for small towns, etc., I'm hoping that will be sufficient for the breakin. I think I'll do as you did and have the rearend fluid changed out at 10k just in case. I'll have to doublecheck the manual but I think it has synthetic in it.