Modifications to a new truck to increase MPG?

[Snax]

I wouldn't beat yourself up too much over your economy particularly if you are using your truck for truck-type tasks. None of our recommendations will produce much improvement if your use includes allot of towing a 10,000 lb trailer around for example. (Expect 8-9 MPG at best if that is the case.)

On the other hand, allot of highway travel without a trailer could see measureable benefit with a tonneau cover or canopy.

[2TonJellyBean]

I would think that taller tires could also reduce mileage if this truck spends a lot of time at lower and varying speeds.

[Greybrick]

EPA for the 2500HD Vortec MAX 6.0L V8 is about 15city/19hwy mpg, so anything north of that is all good.

[cheapybob]

Unfortunately he never said WHY he needed a 3/4 ton 4x4 truck, or whether the miles on it would be city or highway, etc. If he's using it to go thru deep snow in the winter, none of these things are going to help much.

[cbartists]

Originally Posted by cheapybob

Unfortunately he never said WHY he needed a 3/4 ton 4x4 truck, or whether the miles on it would be city or highway, etc. If he's using it to go thru deep snow in the winter, none of these things are going to help much.

We will use the truck to carry our popup slide in camper made by Outfitter. It is an 8' unit that weights about 900 pds dry. I'm an artist, we travel to 6-7 art shows, mostly in the state so mountainous terrain. In fact, to leave here one must go over at least one mountain pass. Most travel will be in the summer. We will also pull a tiny trailer to the shows. Having a camper will provide us to a better experience at the shows. As well as a safer vehicle to get there. Right now we pull the trailer with our 91 Ford Econoline and use it to live out of at the shows. Not safe and horrible FE.

We'll use the camper for fun too, but in the winter I suspect it won't get driven much at all. Since we have the Subaru for highway miles and I ride my bike mostly.

I apprecaite all of the replies. I hope we can improve our mileage even just a 1 or 2 MPG.

[2TonJellyBean]

It's too bad Chevy doesn't offer the 5.3 in the 2500 series. Actually, it's shameful because the 6.0 is much thirstier and is overkill for many applications that don't need tremendous towing capacity, especially ones like yours where you want the payload capacity but still want decent economy.

Aero drag and weight will be your 2 big issues. Most popups still stick up about a foot over the top of the cab and then arc up backwards from what you want like a boat hull IIRC. That won't be good for aerodynamics, nor will the exposed legs that stick out along the sides. I'm not sure if you could come up with some kind of fairing solution for it, but that would be a big step.

Your best best will be to leave really early and not exceed 50 mph and go even slower if possible. Also, every pound you take affects your mileage so it'll be a matter of loading in stuff based more on needs than wants.

While glancing around on a google for anyone that that might have found a cure for the 6 litre's thirst, I came across this:

"My Wife and I both have 2002 2500HD Suburbans with the 8100. We Both love the way the truck rides and performs. Not the wimpy 1500 soccer mom versions. November of 2006 was the last month to order a 2006 2500HD with the 8100. My dealer really screwed up by not letting me know. He could have sold two new trucks and we could have been 4 model years ahead of the game. Now we have trucks we cannot replace. I hope GM gets its head screwed back on straight and wises up. They had a truck that had no competitor."

Yes, his and hers maximum size, minimum mpg Suburbans! LMAO

Anyway 11 mpg x 2 is 22 mpg, right? LOL

Everyone in that forum was lamenting the loss of the 8.1 litre big block and that new suburbans only hold 4x7s not 4x8s.

[Telco]

Too bad a diesel wouldn't have worked. I don't see why not seeing as diesel has antigel additives, available block heaters and turbochargers to compensate for high altitude and cold weather. The 6.0 under load typically returns half the unloaded mileage on flatland conditions, and isn't all that much fun to drive in mountainous territory, according to 6.0 owners on another board I post to. Not a lot can be done with the mileage, either. Since the truck's projected use is going to be 90 percent hauling in the mountains, you need to concentrate on improving loaded mileage, which is a bit different from unloaded.

You might look into getting the electric fans that come on the halfton trucks, just make sure to carry the fan shroud, clutch fan and tools necessary to go back to the clutch fan on the side of the road if necessary. If you can make a fully loaded mountaintop climb at 4PM in August without boiling over, then it won't be necessary to carry the clutch fan anymore.

Long tube headers will also help some. Don't bother with shorties, they run about 400 bucks and add 10HP on top of the RPM curve. The factory manifolds are pretty much shorty headers anyway, the gain isn't worth the money.

Best thing to do would be to add a Whipple supercharger to the engine. A Whipple produces a lot of low RPM torque, as opposed to a centrifugal which adds on top end power. This should improve mileage on long trips fully loaded, since the engine will have more power available to it. Along with this, call Comp Cams for a camshaft recommendation, they can get you a towing cam that will also help mileage.

Really, for the cost of doing all this to make the 6.0 perform with decent mileage, you could trade into a Duramax turbodiesel, do nothing to it and have effortless mountain towing, a 2-3MPG drop when loaded instead of an 8-12MPG drop, and an engine that is just breaking in at 100K miles instead of just starting to break down. Not to mention better mileage than a gasoline truck when unloaded.

[Telco]

Originally Posted by theclencher

All that, and I wonder how much improvement there will be over the Econoline?

On the 6.0? Not a whole lot of improvement to be had, especially with a heavy load on.

[rvanengen]

Originally Posted by theclencher

jsut liek conv i had w/ pa; wi spend $24000 on prius to replace metro and sav maybee a cupple hunnert on fuel? maeks kno cents.

Why not sell it, and just rent a large PU when you actually need it?? Get the diesel in the summer, and if the winters are SOOO bad that even a block heater and anti-gel won't work, then rent a gasser?? Heck...if you are only out for a few weeks a year...you can get one of the large diesel RV's...on the bus chassis, they get at least 6mpg and you can load all of your stuff inside, and save money on hotels! :-)

Even at $600/wk during the times you rent, you will be BIIIIG $$ ahead over paying for the truck, insurance, depreciation and maintenance. Then just use the savings to really have fun at the shows! Just seems like the "juice isn't worth the squeeze" on this one...

[cheapybob]

Originally Posted by cbartists

We will use the truck to carry our popup slide in camper made by Outfitter. It is an 8' unit that weights about 900 pds dry. I'm an artist, we travel to 6-7 art shows, mostly in the state so mountainous terrain. In fact, to leave here one must go over at least one mountain pass. Most travel will be in the summer. We will also pull a tiny trailer to the shows. Having a camper will provide us to a better experience at the shows. As well as a safer vehicle to get there. Right now we pull the trailer with our 91 Ford Econoline and use it to live out of at the shows. Not safe and horrible FE.

We'll use the camper for fun too, but in the winter I suspect it won't get driven much at all. Since we have the Subaru for highway miles and I ride my bike mostly.

I apprecaite all of the replies. I hope we can improve our mileage even just a 1 or 2 MPG.

That's a good fit for my suggestions, then. They wouldn't have worked if the only time you used it would be to tow a 10,000 lb trailer, but should work just fine for a light but large load and small trailer like that. You might want to check what drive ratio it has in it. What it boils down to is that if its revving higher than it needs to on the highway, the engine could give better efficiency with a lower gear ratio. Taller tires are a cheap/easy way to lower the effective gear ratio if that would help. The cost isn't cheap though, and so whether it has a good payback or not is going to depend on how much you can get selling the original tires. You won't be able to go with LRR tires because you need Load Range tires similar to what come with it. I'd look at getting the same thing or similar to what GM put on it, except taller and thinner if it was me. I'd expect my hot air intake would work, too, if fitted with a door to give it cold air when more power is needed.

If you don't have some sort of trip computer built-in, get a scangauge. How you drive is one of the biggest determining factors as to whether you get optimum mpg from whatever you have, and adjusting how you drive is free. I can get 2 mpg better than cruise control driving manually at a steady speed out on the highway. The scangauge gives you continuous feedback as to how hard on the pedal you are and what the mpgs are at, so it makes it easy to get the best out of it.