mpg question

I got a 2003 Silverado with the 4.3L 5 speed reg cab short box. i got a k&n filter and a flowmaster 40 series muffler. im getting 16 mpg in city and 18 1/2 on the highway. is this normal. what else can i do to make it better.

ouch. The 4.3 is a v6 so you would think it would get better mileage than the V8, but in reality it is working so much harder it gets the same or worse mileage. I had the 4.3 in a 2002 S-10 and even in that it only got 19-20 MPG. Unfortunately to me that mileage sounds right, maybe a little low but not too far off.

How do you drive, honestly? I have a 2003 Extended Cab with the 4.3 and automatic, and I get 21/22 on the highway. That's driving 60-65 MPH (the speed my truck seems to coast at) and not stomping on it to get up to speed. If I go 70 or above, I drop to 18 MPG, and I can feel the truck working much harder to maintain that speed. Around town I get 17-18 MPG.

I have 26K miles on it, and the mileage has gotten better over time. The first 10k miles or so I got 19 MPG driving the same way on the highway.

I have a bone stock truck, except for the stereo. I don't know if the filter and exhaust help or not. I plan on a bed cover, which may give me a little boost in MPG.

I do drive it a little hard. i do about 80 down the freeway and speed up pretty quickly. i guess its right. but with people saying they get as much or better than me with the 5.3L got me wondering if i should be getting more.

Like Steve ^ Said your asking a smaller motor (4.3) to pull a full size truck around at a speedy pace. The V-8 takes less throttle to get the truck up to speed. If i was to use a heavy foot w/ my truck all the time I would see a terrible decrease in mpg. On the Highway I cruise at 70-75 and usually use a light foot around town and in the city. I see 17-19mpg. My only tip for you is to lighten up on the throttle or buy a V-8.
-Jimmy

I got a 2003 Silverado with the 4.3L 5 speed reg cab short box. i got a k&n filter and a flowmaster 40 series muffler. im getting 16 mpg in city and 18 1/2 on the highway. is this normal. what else can i do to make it better.

I have a 2000 Chevy Silverado, 4.3 (V6), short bed standard cab (pretty much the same as you). I have a K&N filter as well. I get about 19 mpg in city and i get hella good gas mileage on the highway. I'm not sure exactly how many miles but i can tell you that i made almost a 600 mile trip a couple weeks ago and used just a little over half a gallon. You might wanna try switching over to synthetic oil... try Royal Purple, its good stuff. Also think about getting a K&N cold air intake, it should work well with the flowmaster you already have. Hope that helps a little.

i made almost a 600 mile trip a couple weeks ago and used just a little over half a gallon.

Somewhere... there is a typo.... :lol:

I do drive it a little hard. i do about 80 down the freeway and speed up pretty quickly. i guess its right. but with people saying they get as much or better than me with the 5.3L got me wondering if i should be getting more.

I think that answerd your question. If you are accelerating fast, then you are killing your mileage. Driving fast doesn't hurt your mileage nearly as bad as pulling out fast.

The truck I have pictured gets anywhere between 17.5-18.6 just driving it on short trips. I really don't know what it will get on a trip, but I assume 19-20 mpg. And its a 92 model, but I do have 70 series Flowmasters, a TB spacer, and a bed cover.

Somewhere... there is a typo.... :lol:


Yea... Surprisingly i never failed English class.... :sly:

Have an 01' ext cab with the 5.3l. When the truck was new it would never do better than 18 mpg on the highway and that was at 65 mph. Have since installed a K&N FIPK and removed the screen from the MAF. I also installed a stainless Gibson catback sideswept dual exhaust system. Just went on a 120 mile trip. Cruise was set on 72 mph and I got 20.2 mpg. I haven't figured what I'm getting around town but as was mentioned earlier, the quick holeshots will kill your mpg. It's also very true that the smaller engines have to work harder and thus use more gas!

when you remove the screen from the maf does it help with any hp or mpg? how do you do it. do you know if it will mass with my warrenty?

Don't remove the MAF screen there is a tiny wire behind it that is extremely delicate, the screen is there to keep any debris from hitting the wire and damaging the sensor. Yes removing the screen will void the warranty on the sensor. If you want a MAF with improved airflow then buy a Granatelli from stillen they don't have a screen but they have a beefed up sensor wire.

Best my truck does is 17mpg

I have a 98 ext cab short bed with the hard cover and a 5.0, I see 17mpg in the city and 21 on highway. On long trips I see 23-24mpg @ 75-80mph. My trucks sweet spot is @ 75mph.

I have a 98 ext cab short bed with the hard cover and a 5.0, I see 17mpg in the city and 21 on highway. On long trips I see 23-24mpg @ 75-80mph. My trucks sweet spot is @ 75mph.

What mods have you done to the truck? I've heard that the hardtop helps out with mpg but it's not practical for me.

The only mod I have done is the hard cover, everything else is bone stock. The cover is hard to see in this pic but they look really good, esecially if you spend a few extra $$$ and get the one like mine which has the lines that follow the hood lines.
http://files.automotiveforums.com/gallery/watermark.php?file=/503/212108PICT0003554545-med.jpg

I would say try the synthetic oil. My dad has a 2002 Chevy 1500, short box auto, reg cab, 3.42. At first he got about 18 city and 21 hwy. He switched to Moble 1 and now gets much better. We took it up north (600 mile trip) and we got over 26 MPG! This was doing around 70-75mph. He also has a tonneu cover, I'm not sure how much that helps in the end but it looks good.