Better Gas Mileage Mods

Brad92 · December 15, 2009

I have a 2002 GMC Sierra 1500 2wd 4.3 V6 Vin code W. Currently am getting about 16.5, best I have ever gotten was 17. I drive pretty much all highway at around 70 mph. I have 265/70/16 A/T tires on it, K&N drop in filter with the Kennedy Airbox mod (opened up the airbox), V6 throttle blade mod, and a plugged resonator. I already changed the plugs and got about .5 to 1 mpg improvement. I will probably get a custom tune eventually, but need to save up for it. I know all the usual crap like air up your tires, drive slow and use cruise control. I probably will get a muffler, just for sound, not expecting any mpg increase. Any help would be appreciated.

uh6tdrvr · December 15, 2009

Your best bet is with a tune. It will give you your best options and most performance benifit. As far as a muffler, if you go anything too free flowing, you will probably loose a little low end.

The reality that most people dont realize is that a 5.3 will do the same if not better than the 4.3 just because the 4.3 has to work more to do the same thing as the v8. Its when you put your foot in it that it drinks more. I can get 18-19 on the highway with my 09 5.3 CC 4wd z71....and thats with the cruise set at about 77. My 02 4wd suburban got 17 on the highway in the mid 70's.

peteking · December 15, 2009

Your best bet is with a tune. It will give you your best options and most performance benifit. As far as a muffler, if you go anything too free flowing, you will probably loose a little low end.
The reality that most people dont realize is that a 5.3 will do the same if not better than the 4.3 just because the 4.3 has to work more to do the same thing as the v8. Its when you put your foot in it that it drinks more. I can get 18-19 on the highway with my 09 5.3 CC 4wd z71....and thats with the cruise set at about 77. My 02 4wd suburban got 17 on the highway in the mid 70's.

^^ +1. The higher RPM's on the smaller engine will make it drink more gas in order to move the same amount of mass. You're better off with a good tune, and maybe some highway tires. Next best way to save gas is to ride a bike!

Brad92 · December 15, 2009

Yeah, I have been around GM trucks for awhile as that is mainly what my entire family drives truckwise. I was interested in a 5.3 swap, but I am in college. I do believe that the 5.3 is probably the best gas mileage V8 Chevy has had, and am not really impressed with the 4.8. I have also seen how an extended cab 4.3 will get terrible gas mileage compared to an ext. cab 5.3 because of the extra weight. My truck is pretty peppy, it is indestructable (I had to pull about 8,000 lbs with no trailer brakes with it one time in a pinch, took it slow and have had no problems since). I got this truck from my uncle at an amazing price about 3 yrs ago and don't want to invest a lot of money in it because I am looking towards my next truck in the future. I'll probably get a Duramax later on.

So right now I am just looking at cheap things I can do to boost gas mileage. I drive about 80 miles to and from school. I was impressed with just the difference with new plugs vs the old ones. My wires look good. I am not gonna get highway tires because I live in the country on 15 acres and just the roads to get to the land can get pretty interesting mud wise.

jro909 · December 15, 2009

blackbear tune or the lighter gas pedal foot mod its amazing and cheap

Brad92 · December 15, 2009

Yeah.... don't think that mod is gonna work for me.

Silverado4x4 · December 16, 2009

All the money your dumping into the truck for better fuel mileage and now talking about a tune its going to take a long time to get your money back in fuel savings to pay for all of that and then start benefiting from it.

Toadz · January 13, 2010

Electric fans will help a ton by taking rotating mass off that poor overworked V6. Next time you get tires get skinnier tires as the more contact you have with the road the more resistance there is.

butzers09silverado · January 14, 2010

blackbear tune or the lighter gas pedal foot mod its amazing and cheap

maybe he should've thought about that before he bought the truck...

just having a little fun touche I say lol.

back on topic real quick, tire pressure is a good trick but you have to watch tire wear to see how high you can go on the pressure before you get too much wear in the middle of the tire, OR how bad of a ride you can stand lol. I'm finding so far 38 up front is working with between 28-32 in the rears (60% of the weight is up front anyways)

another trick is i have power folding mirrors and just fold them in on the highway (I don't change lanes often)

find a truck to follow, that works too.