2nd Gen Non-Engine/Transmission 02 towing mileage?

[TJarecke]

My buddy has an 02 reg cab, 5spd, 4x4, 3. 55s. I think it only has about 50k on the clock. The lift pump was relocated to the tank by the dealer. The only mods are an ez, dual 4 inch exhaust, and a BHAF.

In town he gets about 17mpg but towing his mileage falls to 10mpg. This isn't heavy either. The load is about 6000lbs @ 70mph (2100 rpms) on the Nebraska interstate (pretty flat)

He isn't very happy with the towing mileage. Is there an issue or is this normal for this year truck?

Sorry no gauges to tell you more.

 

[RustyJC]

The few times I've run my truck on the Interstate unloaded, it would get around 16-17 MPG at around 75 MPH. When towing, I get from 9. 5 MPG to 11 MPG, depending on speed and terrain (9. 5 MPG @ 70+ MPH in the Texas Hill Country; 11 MPG @ 63-65 MPH on I-30 in Arkansas. Our 5th wheel has a 16K GVWR and is 13'2" tall. More important than weight is frontal area - what's the configuration of the trailer your friend is towing?



Rusty

 

[jeepit]

I have 51,000 miles on and I think it just got broken in. I can get 19 unloaded and 15 towing now with mods you see below.

 

[TJarecke]

He pulls a bumper pull car trailer with 7k axles and a 97 jeep TJ over the axles.

The jeep does sit pretty high. (lifted on 40s)

Lost about 1mpg with the ez?

 

[litespeed]

That sounds about right.



I get 15 to 16 on the highway over 75 MPG. Over 17 under 65 MPH.



I get 9 to 11 pulling our 17,000 lb. 5th wheel at 65 MPH.



When I have pulled cars and other small campers I have been able to get 12 or 13 somethimes. I still think 10 to 11 is the norm.



It is dependant on a lot of factors though. IE: crosswinds, headwind, tailwind, height of camper (or trailer), tire pressure (or lack of it) and the condition of the trailer.



He could try dropping the RPM's to around 1900. That would probably make at least 1 or more MPG difference.



I can tell you right now... ..... If you are going 70 MPH pulling anything, the mileage is going to suffer. If he dropped the RPM's just a tad and tried going about 65 MPH... . He would be seeing 13 MPG. Maybe a tad better if the conditions are right.



AJ

 

[TJarecke]

I am going to tell him this and he is going to want to go trade it for a duramax! We talked him into the cummins, even though he is a big chevy guy.

We got better mileage with our buddies 03 pulling my brothers cummins weighing it at 8475 with a bigger trailer through a much hillier highway.

I guess it could be the speed.

 

[RustyJC]

I am going to tell him this and he is going to want to go trade it for a duramax! We talked him into the cummins, even though he is a big chevy guy.

In that case, I'm certain that he will be extremely happy with his new Duramax.



Rusty

 

[litespeed]

I am going to tell him this and he is going to want to go trade it for a duramax! We talked him into the cummins, even though he is a big chevy guy.

We got better mileage with our buddies 03 pulling my brothers cummins weighing it at 8475 with a bigger trailer through a much hillier highway.

I guess it could be the speed.

I had an 03 Duramax.



Mileage numbers were the same. Within . 5 to 1 MPG either way at the same speeds. But there were times I was sure the transmission was going to overheat and explode. It ran REALLY hot.



Then there was the injector fiasco with Chevy. Truck sat for over a month in the Chevy dealer waiting for parts. They really dropped the ball on that whole deal.



I scrapped the Chevy and got the current truck in my sig. It is a pulling machine. I'm not brand loyal... . The Dodge just works better with the heavy weight I'm pulling.



I will tell you this. If most of your driving is without a load... . The Chevy killed the Dodge. Much easier to drive, smoother, quieter, etc... .



Dont let the problems I mentioned influence his decision. It is all relative (if you know what I mean).



Also, keep in mind that when you talk to people about mileage... . A lot of them lie, go by the overhead read out (stupid), dont know how to calculate it or dont know how to calculate and correct it.



Tell your friend I said good luck. Tough decision.











Edit... .



All my posts are in regards to Duallys..... Not the 2500... .





AJ

 

[TJarecke]

He doesn't have the overhead so that isn't an issue. I am sure he will get a duramax eventually, this may not put him over the edge since he is trying to buy a house right now.

I would agree with you about the comfort and ease of driving. My brother has an 04 duramax.

 

[Fishin Guide]

On my '02, a bad lift pump dropped my milage significantly with only 3500-4000 in tow. My guess is the VP was cavitating the fuel (starving) and delaying the injection cycle, or compressing air and causes a retarded cycle.



So, what is his fuel pressure? The in tank pump was also done on my dad's stock truck. Also an '02. Towing milage at 65-70 dropped from 15 to 10 with no other changes. He can pull the pressure down below 5 psi now.



My truck now gets about 18mpg towing my jet sled. It's only around 3500 lbs. And I tow at 70mph. I have 3. 54s, 285's and an auto. I get 23 mpg unloaded at 70 mph. This is with the fueling box off and the Smarty on 7 or 9. I figure my box off HP is around 450.



Also, he could have a bad EZ. I got a solid 2 MPG improvement from nothign else than the original EZ I used. The added timing should help a bunch with milage. I now run a Smarty and the numbers are about the same.



i checked with a buddy of mine with his trailer. Boat only is 6K. With trailer approx 7500 lbs. 5 Speed, twins, M4's, cam, Drag Comp on 3, he gets over 15 mpg. This thing is as tall as a house as well.



Dave

 

[TJarecke]

I have yet to ride or drive the truck with the ez, but he said it feels alot better. I think he is actually the only one that has driven it since I helped him install the ez.

He doesn't have gauges, we said he should get them, but he doesn't want to spend the $$$.

I read in the latest TDR mag, that the in tank retrofit doesn't necessarily solve the fueling problems since the vp44 needs volume and pressure as opposed to the newer cp3 that needs volume. I think he is under the impression that it fixed the problem since he hasn't felt the low power issue he had when towing with the previous pump.

I don't think he will want to hear that he should get a fuel press. gauge or other gauges.

Thanks for the input on the issue.

 

[mtnrambo]

towing fuel mileage

I get around 12mpg at 17,000 pounds gross pulling the camper since I took the stupid bug deflector off the front of the truck... but I run in the mid 70mph range...



I can also wash my windshield in 1 cycle without that stupid bug deflector...

 

[Cummins Thunder]

He NEEDS to get a fuel pressure gauge on the thing. I have learned to just let people buy what ever vehicle they want. Or else they will never be happy with it.



If that truck has low fuel pressure it WILL take out the VP-44.



CJ

 

[JL penner]

I get around 19 to 20 unloaded on the highway if I keep it around 65 to 70. Around 75 and above it'll drop to 16 to 17 depending on how much I play around and how fast I'm going.



Loaded I get around 14 to 15 pulling a 3 horse trailer loaded if I stay around 60 to 65.

 

[TJarecke]

Thanks for the replies guys. He also has a leveling kit on the truck which could cause a drop in mileage coupled with the bug deflector.

I will tell him what you have told me and remind him AGAIN about gauges.

 

[IRNGOAT]

I just got back from a trip Okc. to silverton Co. Going up(long uphill grade) I got between 13 &14 mpg at 65 and 70 mph, coming home (same route but down the same grade) at between 75 & 80 mph where possible, I got just a tad under 15 mpg . All while pulling my trailer whith jeep . Idont know what the trailer weighs (guessing between 3500&4000 lbs )but I know the jeep weighs 3300 lbs. I'm Happy whith those numbers!

 

[TFD1953]

02 Mileage

My 02 w/275 horse injectors and EZ gets an honest 21 mpg down the highway if driven 75 or below. Above that it drops to about 19. Now for the towing... ... ... . about a million things effect it. My 6000 lb gooseneck empty will drop mileage to about 16. Add 5000 lbs to said trailer and you have 13 or so. Put 11 round bales of hay at 1300lb per and you'll see 10-11. Now for the variable... ... . how fast you speed up, where you shift, etc. , etc have huge effects on the above numbers causing variations as much as another 10% plus or minus. Over all, not really that bad, but you HAVE to think and pay atention.

 

[mhenon]

I am going to tell him this and he is going to want to go trade it for a duramax! We talked him into the cummins, even though he is a big chevy guy.

We got better mileage with our buddies 03 pulling my brothers cummins weighing it at 8475 with a bigger trailer through a much hillier highway.

I guess it could be the speed.

The mileage sounds low to me. I'm towing a 10K lb TT and get 11 to 13. 5 depending on the winds. Towing speed is 63mph using CC whenever possible.

As far as a Duramax getting better mileage. . that shouldn't happen. I've traveled with several friends pulling with the Duramax and they don't do as well as my Dodge/Cummins.

If you're a Chevy guy though... you'll never be happy with Dodge. The Chevy's have all the amenities and are a much better ride (read that soft. . car like). Dodge has always been a working truck to me. 90% of the farmers/ranchers here in Idaho seem to agree.

Mike

 

[TJarecke]

Ok the thread is old but,

After I read as much as I could and reported to my roomate what I had found. He must have let it go in one ear and out the other. He did nothing I suggested except take off his bug deflector. What does he do? He takes the ez off and takes it into the dealer and pays them $60 to tell them that the lift, tires, and his BHAF are causing the problem. They didn't check the lift pump, map sensor, or IAT sensor.

Now he checks his in town mileage on one tank and it is around 15. 5mpg. He swares it used to be 17. So now the truck, sans ez, is in at another diesel shop. Not sure what for, but the guy says he is going to start by adjusting the valves. We will see what happens.

Oh and he has went and looked at some Duramaxes like I said he would. I know it is his truck and his money but it is agravating when someone comes to you for help, you spend your time helping them and then they don't have any interest in listening.

Sorry for the rant.