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2006 Dodge 5.9 cummins diesel

Our 2006 Dodge 4x4 dually 3500 (lonestar) 5.9 cummins, has 170,000 original miles, but has a newer 5.9 motor, 60,000 +/- miles on this motor (according to dealership). ONLY in the SUMMER HOT months and only if we haul a large load of cattle for several miles, (50 to 100). Once we stop at end of off ramp, and are idling at a stop, the motor will start to stall, cutting out, bells will go off in cab, but the truck never actually dies. We have had it looked at several times, one dealership states that it is all 6 fuel injectors, however our warranty company told us to go pick up the truck, that that dealership was inaccurate in their diagnosis. We currently fill up and add a quart of auto transmission fluid to each fill up. This has worked for about a year, we are experiencing this again. HELP, I can’t afford a new truck, and $5400 in injectors is just crazy.

I am not familiar with the motor, but I’m wondering if the motor is OK and your problem is the transmission. Where is this transmission fluid you are adding going? Is it possible the torque converter is not working properly. It seems like a torque converter that does not release properly as you come to a stop would cause a similar symptom.

If the truck starts, restarts, and seems to idle and run with normal power I don’t see how the fuel injectors are bad either. Agree that the diagnosis is faulty.

Good call by @Uncleturbo… This seems like a classic lock up torque converted NOT unlocking when coming to a stop… Its kind of like not stepping on the clutch when stopping in a stick shift car, it going to lug the motor really bad. In your case it must be slipping just enough to allow the motor to keep running. If you turn the truck off, and then start it back up what does it do???

Next time it does this pop it into NEUTRAL and see what it does. That should pinpoint whether the engine or transmission is acting up.

transman

@Uncleturbo:

I don’t disagree with your diagnosis, or the bit about shifting into neutral to isolate the problem to the transmission or engine…but I think you misread what the OP said about the ATF.

He’s putting the fluid in the fuel tank to act as a lubricant and seal conditioner in the fuel delivery system. I drove a International-powered box truck (i.e. an old, ex-U-Haul) with a leaky injector, and the owner did just this to try to get the truck to the end of the trip w/o the downtime of engine work.

(Also, the fact that the ATF trick seems to have bought the OP a year’s reprieve from the problem suggests a fuel issue to me.)

you our adding the atf to the fuel ? that fact is being miss read seams like

have you changed the fuel filter and draining the water separator

Worn out diesel engines can have their lives extended for a while by using the ATF in the fuel trick…Assuming the fuel filter(s) are not plugged up, the injection pump itself may be due for an overhaul.

Instead of guessing and wringing your hands, have the engines compression tested and the injection pump tested for serviceability…I suspect one or both will be found lacking…

That motor should not have any issues with compression at 60K… I have seen them with 500,000k still running strong !!!

The ATF helps keep the injector pump lubricated as well as the injectors which are pressure operated. It takes a minimum of about 4000 PSI to open an injector with pressures as high as 25,000 PSI when running.

transman

A friend of mine had a similar problem with his '01 5.9 liter. After we swapped the fuel pump relay with the wiper relay the trouble hasn’t come back so far. I suggest you try that and see if it helps. The relays are in the electrical distribution panel under the hood. His panel was above the front wheel on the driver’s side.

I can see why the insurance company wanted you to get away from the dealership service. They would have run up a huge bill replacing parts needlessly.

Thanks for all the comments, On the warranty company, they don’t even cover the infectors, so we thought they must be telling us something correct. Anyhow, the ONLY time this truck acts up is when it is over 95 degrees, and we have a huge load. and have asked it to work hard for several miles. Durning the winter months, we have no problem hauling cattle to the sale, and even up into the spring it is fine, only summer months. Thank you all so much, we will have the fuel pump relay checked, and the injector pump checked as well. Thanks again. and we are shooting for 500,000 miles on this truck it is the last one we are buying, after this one we are retiring. LOL