6.7L Cummins Forum

Well it has been about a month since I've had my 09 6.7 in for an engine code and they cleaned egr and turbo. At the time I noticed that my exhaust brake was starting to cycle and I mentioned it to the service writer.

Well now I just purchase a new fith wheel and going over the sierra this last weekend was a bummer.

Traveling down hill my exhuast brake would cycle from more intensity to less intensity and was very disturbing particularly as I travel over areas of ice where when it would increase in intensity it would break my wheels loose.

I will be taking it back to the dealer again but any ideas out there

Thanks


Bill

I really hate to inform you, but, you should NEVER use your cruise control or the EB when the road conditions are poor or even questionable. Just my experience from alot of OTR miles and a whole bunch of miles on the 07.5 rig towing trailers (besides the manual states that too). The EB souldn't surge as you suggest but they will feather in and out when in cruise to keep your speed constant. By the way (Knock on Wood) I have never had my EGR cleaned.

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07.5 3500 Quad, SRW, 4X4, Laramie, Leathered, Dark Metallic Gray, 6.7, 68RFE, 20K Reese, Ride Rite's, 2 Viair air compressors, Bully steps, Kleinn Locomotive air horns (5 in all), Billet polished locking fuel door, 'A' pillar mount Auto Meter Pryo, PML X-deep trans pan
06 Durango 285 RL 5'er Lifted by KZ

Garlic,

You might be right in most circumstances but in our situation going down 8% grades were not talking about going fast. We are going down at 15 to 20 mph in four wheel drive and in icy conditions having all 4 wheels part of the braking process makes for better control. Yes there are times when nothing works and you better have chains on. I never referred to using cruise in 4 wheel conditions and that seems rather obvious that it should not be used. On the Western side of the Sierra conditions are quite different where you are as storms come rushing in from the pacific and can be very wet with combinations of cold and slusshy conditons.

When we were traveling the other day to San Jose the conditions didn't require chains but there were areas where ice was in shady areas and the inconsistency of the exhaust brake was very trying. As we approached each shady area believe me we slowed down in advance but having the exhaust brake can be quite an advantage in these areas. As with brakes any device that attempts to slow you down can be a problem when you hit ice. So it is a matter of swithching from brakes to eb or holding on when your only choice is to keep the wheels turning to maintain control. I have lived, hauled and traveled this country for over 40 years and haven't wrecked yet.

As I mentioned the problem is the cylcing exhaust brake I was hoping that you might have an idea what was happening. I will be taking the truck in this week or next to try and get a resolve to this problem.

Thanks,

Bill

Never seen this but I also live in the Flat Lands. I do want to know what you find out since the 6.7L is the first to have the integrated Exhaust brake.

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2007.5 Dodge Ram 3500 HD,QC, 6.7L Cummins, 6speed Auto, 4X4, Bighorn Edition.
Click for installs: Carr Steps PML Diff Cover Edge Juice with Attitude Volant Intake Hankook ATM RF10

Garlic,

We pretty far out about 50 miles one to Carson Dodge. Hope to get in this week and see what's up. Will let you all know as soon as it is figured out.

Bill

Soccerloco, I didn't mean to be critical of your driving style or experience. Do you think the engine rpm's or vehicle speed may have been a contributing factor? I don't know, hope the dealer is of assistance to you and hope to hear a positive responce back from them, good luck.

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07.5 3500 Quad, SRW, 4X4, Laramie, Leathered, Dark Metallic Gray, 6.7, 68RFE, 20K Reese, Ride Rite's, 2 Viair air compressors, Bully steps, Kleinn Locomotive air horns (5 in all), Billet polished locking fuel door, 'A' pillar mount Auto Meter Pryo, PML X-deep trans pan
06 Durango 285 RL 5'er Lifted by KZ

Garlic,

No offense taken have had a family tragedy and have not taken pickup in yet.

It is wierd the truck runs well but when I use exhaust brake, which is almost always, hauling my trailer as the truck starts to slow down the eb cycles from more intensity to less.

Again my duty cycles are get in the pickup haul my trailer drive at least 160 miles no stop and go but typically I cross the sierra.

This week will be a trip to Las Vegas so no real mountain driving.

Hoping to take pickup in tomorrow.

Will keep you all posted.

Bill

Ah ha.

Just talked to service writer regarding my cycling exhaust brake and here is the problem they discovered.

The truck was just in before Christmas for a dirty turbo code and at that time I was getting some of this cycling in the exhaust brake. At that point they cleaned the turbo and cleaned the EGR valve.

After their work the exhaust brake cycling was even worse than before and low and behold on this most current trip to the dealer they disclosed to me that the EGR valve was sticking open causing the exhaust brake to go between high stopping value to not much stopping value back to high.

I am a bit confused because they had just cleaned the EGR.

Now my most recent drive over the mountain involved about 525 miles of driving so what would be the result to my engine with the EGR valve stuck open? And does stuck open EGR valve affect the exhaust brake like this.

As I have said in the past I use my truck for work only no stop and go driving and I tow about an 11,000 5th wheel when I use it.

I often encouter long grades down hill where I might be off the throttle for 10 to 15 miles at a time could this be a problem. I run the exhaust brake almost 100% of the time.

Given my duty cycles I never thought I would have emission problems.

Please let me know what you think......

Bill

I would think the fuel mileage and the power would go away some, but that seems to make sense if you had an exhaust leak, but no CEL? go figure.

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07.5 3500 Quad, SRW, 4X4, Laramie, Leathered, Dark Metallic Gray, 6.7, 68RFE, 20K Reese, Ride Rite's, 2 Viair air compressors, Bully steps, Kleinn Locomotive air horns (5 in all), Billet polished locking fuel door, 'A' pillar mount Auto Meter Pryo, PML X-deep trans pan
06 Durango 285 RL 5'er Lifted by KZ

Here is the latest on my cycling exhaust brake. Took in to the dealer where it was determined that there were no codes thrown. On inspection found that the EGR valve was stuck in parital apply position and found that flow control vlave could not be actuated by hand. Replaced EGR valve and flow control valve. When I drove the truck home it felt as though the exhaust brake was working more effectively. Next day connected my trailer and headed to San Francisco over Highway 50 and the first downhill I came to the EB did the very same thing pulsing, Cycling, or whatever you want to call it.

On my trip the Carson City Dodge Service folks called to me to see how the truck was working and I had to give them the bad news.

When I returned on Tuesday I took the truck and trailer in and had the tech ride with me as he connected a diagnostic unit to check the performance of the truck. First thing as we descended Spooner Pass thank God the truck got right into the pulsating, cylcing or as the tech called it a harmonic situation. It appeared to the tech that the turbo and other parameters were within specs.

Now the tech is emailing Cummins engineer and I am waiting for what I believe they called and RON.

This is the first time the tech has seen any thing like this....Me too.

I feel the tech is very interested in getting this resolved and I will be happy to have my exhaust brake back in working order.

Will let you know when information becomes available of my continuing saga.