Fuel Economy Boost - Coast

[jerryreliable]

Hi, I have a 2006 Chevy 1500 crewcab, LT3, 5.3 V-8. 373 rear, stock, 15K miles. Thbis truck has the mileage computer, I have checked it with the trip odometer and the gallons at most fillups, it is accurate. I get 21.3 miles per gallon in combined city and highway driving, and I signed up to tell you how I do it. Some years ago, I read a book about driving in Russia, the high cost of gas, and how they drove to get the best mileage. They do a lot of coasting. I actually began this type of driving with my last truck, an F-150 with lousy mileage, 2005 Crew if you're interested. It didn't work, because the computer didn't return the engine to idle when coasting in neutral at speed. I bought this truck for the advertised mileage, and found it a bit low. I started the coasting a bit, and it improved. Then I improved the technique. Actually now, I am getting this mileage with even some trailer towing, and loaded. Here's how: Chevy builds a smooth coasting truck. I can see a green light well over a half mile ahead, and I know it is a short cycle light. I neutral up, and coast. I am doing 50, the speed limit is 50, and the light begins to turn, yellow, then red. I am slowing as the other cars are, only my engine is at 500 plus rpm. If I have to wait for the light, I leave the transmission in neutral until the light turns green, putting it in gear as it is time to move. You see, if the engine is in neutral, it requires only 60 percent of the fuel it uses sitting there in forward. Sometimes the light turns green before I get to the intersection, and then I continue to coast until the cars ahead of me have began to move and are up to my speed. The law of inertia in this case saves a lot of fuel. Going home, my turn off street is labeled 30mph. Lots of people speed up to the S curve, slow down by braking, and accelerate out of the curve. Their daily driving is rushing to the next stop. I turn on the road, accelerate to 35mph, and put it in neutral. When I get to the S curve, sometimes I have to brake a bit, but I get through it just as quickly. On roads posted 45-55 mph, I find the optimum speed is 49mph. On interstates, the 70mph eats into the average, but in combined driving it always comes back to 21.3MPG. The joke is, my wife has a V-8 Mustang convertible, and she is trying to do the same thing, and the truck is a mile per gallon ahead. So, I hope this helps you attain the mileage you are looking for. I do think it is possible to get even higher average combined mileage, but I keep having to tow big boats short distances, and that keeps it where it is. I'd like to have one of the 2007's or newer with the active fuel management engines, just to see the difference. I tried the hybrid 2005 silverado, but the best mileage posted wasn't over 20. By the way, I am in the marine towing business, and therefore the obsession with economy, but here, you have the economy and one heck of a nice truck too. Jerry Smith, Florida coaster.

[-Devil-]

thats why i liked my old standard ... pop the clutch in for those instances ...

[masterp2]

thats why i liked my old standard ... pop the clutch in for those instances ...

 

he's not releasing his clutch. He is shifting out of gear. Jerry, learn from a few safety experts. You are putting yourself at risk.

[wellinghurst]

This is a type of driving that some call "hyperdriving." It works, butits way too much trouble for me. I'm not to that point yet with regards to gas. There was a guy doing this in a manual Mini Cooper on Discovery HD the other night and got 50 mpgs in town (they're rated for around 30).

[punmax]

I brake hard and punch the throttle ;)

[Wingnut]

Jerry, if you just use cruise on the interstate at 63-65 mph, you'll get 21+ MPG that way too. My '02 with the same engine and gear ratio would anyway. Increasing my speed to around 70 would drop it by several MPG.

 

I did it time and again just to make sure it wasn't a fluke. I couldn't believe that I was getting over 20 MPG with the AC on over long distances in a 6k lb truck with a 300 horse V8.

 

I can't comment on the neutral thing though...I wouldn't drive that way. If something happened that required a split-second maneuver other than braking, you'd be screwed.

[mljenkins]

I tried driving in neutral in the Mercury Sable I had. I only did it a few times because I wasn't sure about what effects it could have on the transmission. Plus if you forget you are in neutral and punch the gas I doubt that is so good on the engine. I have not done it in my truck. It's interesting from your and other posts here that it is an actual technique used by drivers. I suppose the best bet would probably be to have a manual and use the clutch to improve gas mileage by coasting out of gear.

 

I saw a sticker on the side of some Chevy car (forget the make) that summed it up: "Brakes are for pus**s" (of course it wasn't censored). I drive very conservatively, not using neutral, but by allowing plenty of coast time before I have to stop at lights. Chances are the light will turn green again and I will have some momentum. But better yet, it keeps me from being rear ended from people on their cell phones eating a burger behind me (i.e. not paying attention, we've all done it in some form). I do the same for upcoming turns. Now of course this all goes to heck when I'm in a bad mood or in a big hurry. But seriously, unless you have a hybrid with regenerative braking, every time you hit the brake you are wasting energy, which translates into fuel. Driving habits definitely are linked with gas mileage. IMHO, less fuel costs = more mods :-)

 

I agree with the others about cruise. I started getting much better mileage with cruise on. As soon as I get on the interstate I turn it on. Now the most annoying thing I find is people who don't use their cruise, because you try to pass them with cruise on and they instinctively speed up. Cruise also helps avoiding speeding tickets because you're not punching the gas to the music... (does anyone else have that habit?). I think I average between 15-17 mpg, but I have a lot of rural driving to do coming home. I am interested what the future will bring in gas mileage, especially with those new standards the President signed into law this past week.

 

Matt

[jerryreliable]

I tried driving in neutral in the Mercury Sable I had. I only did it a few times because I wasn't sure about what effects it could have on the transmission. Plus if you forget you are in neutral and punch the gas I doubt that is so good on the engine. I have not done it in my truck. It's interesting from your and other posts here that it is an actual technique used by drivers. I suppose the best bet would probably be to have a manual and use the clutch to improve gas mileage by coasting out of gear.

 

I saw a sticker on the side of some Chevy car (forget the make) that summed it up: "Brakes are for pus**s" (of course it wasn't censored). I drive very conservatively, not using neutral, but by allowing plenty of coast time before I have to stop at lights. Chances are the light will turn green again and I will have some momentum. But better yet, it keeps me from being rear ended from people on their cell phones eating a burger behind me (i.e. not paying attention, we've all done it in some form). I do the same for upcoming turns. Now of course this all goes to heck when I'm in a bad mood or in a big hurry. But seriously, unless you have a hybrid with regenerative braking, every time you hit the brake you are wasting energy, which translates into fuel. Driving habits definitely are linked with gas mileage. IMHO, less fuel costs = more mods :-)

 

I agree with the others about cruise. I started getting much better mileage with cruise on. As soon as I get on the interstate I turn it on. Now the most annoying thing I find is people who don't use their cruise, because you try to pass them with cruise on and they instinctively speed up. Cruise also helps avoiding speeding tickets because you're not punching the gas to the music... (does anyone else have that habit?). I think I average between 15-17 mpg, but I have a lot of rural driving to do coming home. I am interested what the future will bring in gas mileage, especially with those new standards the President signed into law this past week.

 

Matt

 

 

 

Thanks Matt,

 

Actually, I just didn't mention the cruise, but it is an integral part of this coasting scheme. I really didn't mention quite a bit about it, because I figured those folks who wanted to improve their mileage would figure it out, just as those folk who like to drive aggressively would continue to do so. Most all of the 15000 plus miles on my truck have been this style of driving. No problems with the truck in any way. Yeah, there could be a safety issue like stepping on the gas with the engine in neutral in the middle of an intersection, but just paying attention seems to do the trick.

[-Devil-]

in my truck ... my cruise is set any time i have more then a block to travel at the same speed ...

 

so far i am now averaging almost 19mpg (for city and highway combined) just recently i switched over to synthetic ... so i am figuring i may squeek another .5 out of it ... and then once the motor gets closer to 10k miles maybe another .5 at the most

 

but, its a truck ... if i wanted 30+ mpg i would hop in the little dodge neon sitting in my front yard.