I just purchased a 03, 3500, quad cab, DRW, cummins a few weeks ago. i upgraded from my durango to be able to tow a 7x14 enclosed trailer (2000 lbs).

what i know about the truck
- 125k on the clock
- new tranny
- 2WD
- told it had a limiter or chip or something that kept it from going more than 2k on the interestate. ( it will cruise at 70 no prob not towing)


this weekend i finally got a chance to tow with the truck, and i was super unimpressed. I could not tow more than 58-65 mph on the interstate with the trailer in or out of OD. for being a 3500 diesel i expected to be able cruise at no problem at 70mph with that trailer. I watched for three hours smaller trucks pull larger loads and blow our doors off. just on the up and down of the overpasses it would slow down to 55 mph sometimes.

is this right, that it will not tow past 65mph? is there such thing as a limiter or programmer?

is there anything i can do?

This is my first big truck, and first diesel, so i am new to this and could use some serious help.

thanks again

 

The Durango would have pulled the 2k lbs trailer............only reason I say that is you probably spent some money doing the "upgrade"


I have a Superchips tuner on my Ram 1500, and I don't think there is an option to limit it to a mph unless you alter the limiter, but you would hear that. What RPM's would it not pull past? Could the previous owner have had the pcm flashed? Don't know why it would alter it only when towing though....got me on that one

 

the durango would pull the temp up to 3/4 towing the trailer. i did not think the motor would last long like that.

i did not mind upgrading as i would like to pull a toy hauler in the next 18 months or so, but right now, i dont know if this truck will do it, from what i see.

i dont know much about flashing the ecm or chips for this, is there a way i can tell if its been flashed or chipped? and how do i put it back to stock? not towing it will tell me 18 mpg, but towing yesterday said 12 mpg. i did get it up to 67 mph if i drafted a semi truck, but that is not what i want to be doing, i just dont think something is right and i dont know where to start looking for any issues.

 

Yeah something doesn't sound right for sure man, it should pull way more than that, and go faster if you like.


I don't personally know how to tell if an pcm has been flashed, maybe a more experienced member in this matter will be along shortly

 

Well, first off I'm a long way from being an expert. But that dually diesel should pull 2000lbs like there was nothing back there. Truck will not go over 2000 RPM? Definitely a problem somewhere. I've never heard of a 'limiter', maybe the previous owner had a programmer on it and if I remember, some brands had a 'valet' selection. Which limited/detuned power so anyone else couldn't beat on the truck to bad. It sounds like you didn't get a programmer with the truck, so the only option I believe is to go to a dealer and have them flash the computer. This would take it to the stock program and eliminate any aftermarket programming. Look around under the hood for any add on electronic boxes and remove them.

Also just a thought, tranny isn't slipping is it? fuel filter good, fuel pressure good?

 

valet selection? where is that? there is a toggle switch to the left of the steering wheel, that i have no clue to what i goes to.

i could not tell you if the filter or pressure is good or not. the truck runs ok, and there is no codes visible.

 

It's not a switch persay, some programmers have a tune burned into the tuner/pcm for valet mode. To access it, you would need the tuner.

Stopping by a shop that can tell you if the pcm has been flashed would be a good start.

 

founda shop that does diesels and 4x4 stuff. $75 for a diagnosis and give it a once over to see where there are any issues.

 

I'd say you need to have someone look at it. I pull a 7700# tractor and a rough cut mower on a dual axle trailer with my 1500 with Hemi. I haven't had it over about 60 mph pulling it as I am on paved 2 lane with 55 mph speed limit and I wouldn't push it anyway at the upper end of my trucks' limit. But I feel like it'll do a lot more just with my gasser.

MPGs suck, but the power is there for sure.

Been in many a CTD pulling upwards of 9000# and they had no problem, so I'd say you've got an issue going on...

 

welp, took it to a buddy of mine that deals with diesels. turns out that before i purchased the truck it got a whole new A/C system. when they worked on the A/C they forgot to tighten down one of the boost clamps, so it was partially on the truck. got it reattached and clamped down, it runs like a raped date.