Half-ton Towing MPG

[CentralMePistol]

Morning all!
So I picked up my new travel trailer out of state yesterday... pulled great on the way home no issues there. I have hauled before and the MPG was about the same, maybe even a little better.
That said, my highway MPG while towing in tow/haul mode is about 10mpg.

It could be worse I suppose, but its not good thats for sure.

Have any of you used a programmer to tune the truck for better towing and hauling mpg/ performance? Which did you use?

[drittal]

That’s about right

[007matman]

That's pretty good for a half ton truck.

Which one?

[babock]

Ours does 11MPG towing @ 60MPH with the rig in my signature on level.

[MillMitch]

Sorry, can't help with the tuner/truck question. The only tune I have is a 93 octane tune in my Mustang - and yes, i can tell the difference
Seriously though, thinking about it, I'm not sure I would want a tune in a TV. I would try a cold air intake first and let the MAP auto adjust for the higher air flow within the computer. I would be nervous that a tune would lean out the engine. Take this with a grain (or bag) of salt, I'm not a mechanic; but i did a lot of research before getting the tune for the Mustang.

[aceinspp]

That is about average for your truck. Depends how fast you are towing. What gear ratio do you have. I tow 9000# with3/4 ton and 4:10 gear 6.0 eng and average 8.5 to 9mpg at 62 mph. Later RJD

[babock]

Originally Posted by MillMitch

Seriously though, thinking about it, I'm not sure I would want a tune in a TV. I would try a cold air intake first and let the MAP auto adjust for the higher air flow within the computer.

Please explain how you think a CAI would help with MPG at highway speeds. The engine is running at some RPM that is less than 2000RPM. At a given RPM, you consume an exact volume of air. Doesn't matter what intake you have.

A CAI would only help you getting to an extremely high RPM. It's a complete waste of money and just sounds loud. If a CAI would actually make a truck engine perform better, don't you think the OEMs would put them on at the factory?

I used to work for GM. The engineers that design the program for the ECU were always amazed when they heard of what the tuners were doing. They said that they go through 1000s of hours determing the best settings to get the best performance and longevity for the engine and they know the whole system inside and out. How are the tuner people doing something better than they do without really understanding the whole system. Needless to say none of them recommended using tuners.

[CentralMePistol]

Thanks for the thoughts guys...
the big thing I am looking for is a way to put 6th gear back in play when towing on the highway. I have found that If I shut the tow/haul off then the tranny seems to have a hard time finding the right gear. I like how it pulls in tow/haul. I just want it to use 6th gear when at speed.

Also, I have read conflicting information that tow/haul also increases the tranny cooler pressure, making it more effective- I want to be sure that is still turned on.

I was hoping a programmer might open sixth gear back up and extend how long the truck would go before dropping to 5 to maintain speed. When we are talking about these kinds of mpg, even 2-4 extra miles could save $25 per fill up. Doesn't sound like a lot, but if your taking a long haul... that could be several hundred dollars...

[Kimber45]

How heavy is the trailer? I saw a post last week from a guy with an eco diesel ram 1500 claiming 15MPG but it was only a 3 or 4 pound trailer.

[510Rick]

Originally Posted by babock

Please explain how you think a CAI would help with MPG at highway speeds. The engine is running at some RPM that is less than 2000RPM. At a given RPM, you consume an exact volume of air. Doesn't matter what intake you have.

A CAI would only help you getting to an extremely high RPM. It's a complete waste of money and just sounds loud. If a CAI would actually make a truck engine perform better, don't you think the OEMs would put them on at the factory?

I used to work for GM. The engineers that design the program for the ECU were always amazed when they heard of what the tuners were doing. They said that they go through 1000s of hours determing the best settings to get the best performance and longevity for the engine and they know the whole system inside and out. How are the tuner people doing something better than they do without really understanding the whole system. Needless to say none of them recommended using tuners.

I whole heatedly disagree with this . The engineers design the engines and drive train to perform in a way that they get them to drive well but at less then the actual power capability to keep from having to do so much warranty work . Most vehicles are factory tuned with a lot left on the table and some don't even work right with the factory tuning hence the reason 75 percent of diesel trucks are tuned for better mileage smoother shifting and more power where its needed . Conservative tuning can be extremely beneficial in many ways . There are lots of good tuners out there .

[CentralMePistol]

Haven't been on the scales yet....
book 6,000#
I had them put a quarter tank of water in since I hadn't loaded any other gear yet. Guessing about 6,500#

I plan to keep my weight under 7,000# all the time.

[DieselDrax]

So, a couple of things. A common misconception is that higher RPMs = lower MPG. While higher RPMs can reduce fuel economy by a slight increase in friction/drag, simply making a change to allow the truck to run in 6th instead of 5th isn't likely to net an increase in fuel economy. With fuel injection it only injects as much fuel as needed for a given load. If 5th results in the engine running at a more efficient RPM then running in 6th may actually reduce fuel economy because the load on the engine will be higher at lower RPMs that are outside the torque/power band.

If you are thinking you'll be able to somehow get 2-4mpg more while towing your trailer I'm sorry to say that is not going to happen. I'm also not sure how you could save $25 per fill-up, your tank will take the same amount of fuel to fill no matter what your fuel economy is.

Also, a CAI will not help with any newer vehicle that is otherwise stock or even has a tune. Many have shown to reduce power because they pull in hot underhood air instead of the cooler air from the factory location. The air filter is not the limiting factor in airflow, just because you put a filter with a higher CFM rating on your engine doesn't mean your engine is going to flow any more air. How much air the engine flows depends on many things and the OEM filter will flow more than enough air for the stock cam, heads, intake, and exhaust.

A CAI will never provide enough improvement on a modern vehicle to be worth the cost, many other mods would need to be done first. This coming from someone that had a track-prepped car with multiple mods and laptimes showing time improvements.

10mpg is where the OP is going to be, they need to come to terms with it.

[DieselDrax]

Originally Posted by 510Rick

I whole heatedly disagree with this . The engineers design the engines and drive train to perform in a way that they get them to drive well but at less then the actual power capability to keep from having to do so much warranty work . Most vehicles are factory tuned with a lot left on the table and some don't even work right with the factory tuning hence the reason 75 percent of diesel trucks are tuned for better mileage smoother shifting and more power where its needed . Conservative tuning can be extremely beneficial in many ways . There are lots of good tuners out there .

You cannot compare diesel to gas tuning, not even close. Modern gas engines have minimal gains available without doing some $$$ bolt-ons and other major mods. Diesels are easy to get more power out of. The OP doesn't have a diesel.

Originally Posted by Kimber45

How heavy is the trailer? I saw a post last week from a guy with an eco diesel ram 1500 claiming 15MPG but it was only a 3 or 4 pound trailer.

Diesel vs gas, simple as that. Diesel has higher energy content than gasoline, which means less diesel is needed to make the same amount of power which means better fuel economy when pushed hard. Can't compare diesel and gas fuel economy and expect a gas truck to get the same, it just won't happen.

[CentralMePistol]

Thanks for those thoughts... I was hoping to squeeze a little extra out of my gas truck.

The $25 per fill up was meant more in the extra miles between fill ups. Yes, the actual gas amount and cost would be the same. I was thinking the cost/miles per tank.

I appreciate the explanation of the fuel injection, definitely a better perspective.

I think in the end the best option may just be manual mode and/or not using cruise so I can feather the gas.

[babock]

Originally Posted by 510Rick

I whole heatedly disagree with this . The engineers design the engines and drive train to perform in a way that they get them to drive well but at less then the actual power capability to keep from having to do so much warranty work . Most vehicles are factory tuned with a lot left on the table and some don't even work right with the factory tuning hence the reason 75 percent of diesel trucks are tuned for better mileage smoother shifting and more power where its needed . Conservative tuning can be extremely beneficial in many ways . There are lots of good tuners out there .

Wow...so the engineers that know the system inside and out aren't going to tune for maximum efficiency to get better MPG? You actually believe that? Have you actually spoken to the engineers like I have? You don't think that they aren't pushing to get the best MPG to improve the fleet average? And yet people have this notion that the OEMs spec lower viscosity oil to improve mileage by a tenth of a MPG but they won't improve MPG by changing ECU programming. Amazing the myths that get propagated.

The tuner industry is big bucks. They tell you what you want to hear. Same goes for bolt on performance equipment like CAI.

[babock]

Originally Posted by CentralMePistol

I think in the end the best option may just be manual mode and/or not using cruise so I can feather the gas.

Not sure what speed you tow at but if you drop your tow speed even just 5 MPH, you will gain more fuel economy than anything else.

[CentralMePistol]

I tend to tow between 60 and 65 depending on traffic and conditions.

[KyDan]

I get 7 or 8 mpg.
Can I borrow your truck for a couple months??

Don't know if it's even applicable but in -some- trucks running at very low RPM can cause tranny over heat due to low amount of tranny fluid being pumped thru the cooler.

Just a thought.
Don't know about your truck.

Good luck and happy camping!

[Lawrosa]

I agree CAI are a waste unless you have a high RPM/HP engine. Even then your sucking hot air in. The factory GM air box is a high capacity and in no way will you not be able to suck in enough air. Also factor does suck from inside the fender for cool air.

Save your money..

Next tuners.

Putting it in tow haul does much of what a tuner will do for you. GM;s and most cars timing is advanced already. I run some +30 degrees at times.

Tow haul locks the torque converter in sooner, prolongs the shift points, takes the alternator out of fuel savings mode, and locks out OD until about 65 mph. At least on my truck..

save your money

Now overdrive.

The 6 speeds are really a 4 speed with two overdrives. I have a 4 speed so its really a 3 speed with one OD gear.

I tow in 3rd gear. There is no way I will run in OD. OD has two clutch plates only and you will burn those babys up IMO. It makes no sense to have the tranny hunt for OD. I keep it in 3rd, run 75 mph @ 2500 RPM or so with the 3:42 rear. I get 9 mpg towing.

With the 6 speed I would no way in H*** try to run in that gear. I would put it in 4th and be done with it.

My 3rd gear is 1:1 and thats what I like. Direct drive. The 6 speeds 4th is a 1.152 to 1

6 speed comparision

1---4.027 2---2.364 3---1.532 4---1.152 5---0.852 6---0.667

4 speed


1--3.059 2--1.625 3--1.000 4--0.696

As you can see you have a massive 1st gear pulling power. ( and I though my first was low...lol) Your final OD gear aint no different then mine.

With those #'s I probably wouldnt even entertain 5th..

Remeber there are only two clutch plates for overdrive. Tow haul increases line pressure to hold clutches togther. Dont run without it.

Running near a 1 to 1 ratio is what you want in towing IMO. The benefit of more gears inbetwwen is when hitting hills. Im 2nd or nothing. Other trans have more options....Ha ha ha..

[510Rick]

Originally Posted by babock

Wow...so the engineers that know the system inside and out aren't going to tune for maximum efficiency to get better MPG? You actually believe that? Have you actually spoken to the engineers like I have? You don't think that they aren't pushing to get the best MPG to improve the fleet average? And yet people have this notion that the OEMs spec lower viscosity oil to improve mileage by a tenth of a MPG but they won't improve MPG by changing ECU programming. Amazing the myths that get propagated.

The tuner industry is big bucks. They tell you what you want to hear. Same goes for bolt on performance equipment like CAI.

Maybe your engineer buddy's lie since they are paid big bucks to keep secrets ? They are pushing the best mileage they can get with out causing harm to the truck or car in order to keep down warranty expenses . All of these computer controlled vehicles are capable of getting better mileage and a lot more power output . Usually contrary to the norm the more power they program the engine to output the better the mileage . This is especially true with Diesel vehicles.
FWIW I also know your engineer buddys did a terrible job on the GM vehicles with the Active Fuel Management crap they put on the 2007 and newer trucks . You can do your own research on that issue its no secret . Im a GM guy always have been and it pains me to feel this way but when you take care of a huge fleet of vehicles you get a good idea of whats crap and what isnt .