86 Suburban- anything that can be done?
 

Hi All,

I know, a big 3/4 ton 4wd suburban, probably not much that can be done. It does have a huge wing on the back that causes air to curve down the rear of the truck at the rear doors.

Would I be better off to take this off? It doesn't serve any purpose as far as I can tell.

I cannot really do any other mods, perhaps put some spoilers (or whatever they're called) ahead of the wheels to smooth out turbulence around them.

I already drive as conservatively as I can, and will be getting a vacuum gauge soon.

Thanks for any advice. TTFN!

What hurts your fuel economy driving a Suburban is a double whammy: very heavy weight, and poor aerodynamics. That wing is to help keep the rear window cleaner. Without it you will just have to clean the rear more often.

Other than trading to a more Fuel Efficient vehicle, there are plenty of things that you could do to save gas.

Drive less. Get a bicycle. If you live far from work, drive part way then bicycle. Do not let it idle for no reason. Maximum air pressure in tires. Do not allow the cavernous back of that thing become a rolling storage unit. Pretty much read the driving tips, and use as many as are practacle for you. I would advise against engine off coasting, just too dangerous in that kind of vehicle.

Keep in mind that everytime you take off from a stop it takes a large amount of energy to get that heavy thing moving. Taking your time with acceleration will help. Mashing the go pedal will burn lots of fuel, avoid it.

Later,

Allan Greenblazer

Shooo weeeee a 3/4 ton Suburban.* And a 4x4 at that.* I got a '86 Silverado with a fiberglass topper that probably looks alot like that Surburban. It's a 1/2 ton 2wd.* With the 350 & 373 gears, it pulls fine.* right up to a gas pump.* I'll pay the bank over the oil tycoons.* Greedy SOB's.* Gas savings alone could make up the pmts depending on how long you plan to own something.* I'm with Greenblazer on the tire pressure. I just pumped mine up 10 extra psi & seen another 3mpg! that's on a light 4cly, but it'd be worth a try. I squeezed 18mpg out of my wife's Durango 4x4 with tire pressure change & driving technique when she can barely get 15, soooooo. Other then that, Naw, I better not say it.

I don't have a whole lotta hope for major fe improvements via aero on that thing. Yeah, removing the air deflector and doing the usual other, notsoradical tricks will help a wee bit. I think whatever you do without getting radical, you are stuck under (maybe WELL under) 20 mpg which, IMHO, is unacceptable for a daily driver.

As far as screaming deals and paying pumps rather than banks... I've located several free and nearly free econocars without too much effort, and have been getting 27 to 47 mpg with them. There really isn't any reason to pay the pump OR the bank.

Hmmm.... didn't realize I was going to have to brace for impact on this one! ;)

Unfortunately I cannot bike to work, as I am a mobile computer tech. I did used to commute for 3+ years 12mi/day on a fixed gear, later 20mi/day on a recumbent that I built for myself.

I realize that this thing is a brick. I drive very conservatively, don't mash the gas, etc. My main worry was that wing on the back. I'll recheck the tire pressure but IIRC I already aired those up to sidewall maximum. Its worth rechecking though.

As for the driving tips, I've looked through them and I do as much as possible. I coast down hills (putting it in neutral) when they are steep and long, I don't drive insanely fast, and I don't load it down with tons of junk.

Thanks for the responses. I *am* looking at getting something more FE for a work vehicle (thread here: http://ecomodder.com/forum/showthrea...long-6528.html) but for now I have to make lemons out of lemonade. When I bought this truck I didn't have to drive it so much, I had a different job and bike commuted...

You can do it!
 

If you're getting 12mpg and I'm getting 24, you have a much greater opportunity, and need, to save gas. If you bring your 12mpg up to 18, you're saving as much fuel as if I brought my 24mpg up to 72mpg! That's because you burn so many more gallons per mile.

How to go about it? Using the same methods that I would use to reach towards 72mpg. Side skirts, weight reduction (delete rear floormats?), height reduction, replace glass with acrylic.

One thing I'd especially look at is trying to improve your engine's power output per gallon. If it calls for 10W40, install synthetic 0W40. If it has a belt-driven fan, install a thermostatically controlled electric fan. If it's carbeureted, <strike>drive it into a lake</strike> install MegaSquirt. If it's FI, maybe it can run leaner? I wonder if you could lighten the Suburban enough to get a GM 4 cyl to run it. I'll bet a 2.2L, 145HP Ecotec would do it. There's some weight savings right there.

Of course, Mercedes has already made a very eco-friendly 3/4 ton in the Dodge Sprinter van. But you could make the Chevy suck less gas.

Not to mince words, but if I were to go 12 to 18, that'd be the same as you going from 24 to 36, not 72.... that would be like me going from 12 to 36. Not happenin'. FWIW, I had a 87 'burban for a while that was fuel injected, it didn't do much better on gas. 14mpg around town at best.

Synthetic, not a bad idea. Fan, not a bad idea. Engine swap to a 4cyl? Wow.... The V8 it has (a 350) doesn't make more horsepower than that 145hp ecotec, but it would probably take a couple of those ecotec's to get the torque. Torque makes cars go, not horsepower. Horsepower just *keeps* them going. Ah its a useless subject.

Hi, My name is Ryan, and I drive a gas guzzler.

Say you drive a mile.

12 mpg, 1/12 gal. 18 mpg, 1/18 gal. Difference, .028 gal.

24 mpg, 1/24 gal. 72 mpg, 1/72 gal. Difference, .028 gal.

That was what he meant.

With a monster that large, would a full boat-tail make much difference? :P

I also have 2 large gas guzzlers in the family. Both 4 wheel drive, and both used for their intended purpose (hauling and commuting when the weather is more than the neon or wife's intrepid will handle). However, they are paid off and insurance and plates for a year for BOTH of them is less than renting a small u-haul for 2 days.

Some things I have done that you can do to the suburban that helped....

1. Synthetic gear lube in BOTH differentials. If it is an 86, it could likely stand to be changed anyway.
2. free flow exhaust (got me 2 mpg highway on the 1/2 ton truck)
3. Synthetic gear lube in the tranny (if it is a manual)
4. front air dam (these sit pretty high...so it will likely not be an issue unless the snow was REALLy deep)
5. Electric fan (already mentioned) or at least check the clutch on the current fan. They had a tendency to seize on these.


Not a lot of aero, I know....but some ideas.

Jim