I have a 4.3 powered regular cab 4x4. I was getting 15mpg since january when I purchased it. Last week I decided to leave the tailgate down to see if I could improve things. Well it went down to 14.5mpgs. What are you guys doing to squeeze that extra mile out.

Bill

 

keep her under 60

 

there are quite a few ways to do this, ....squeeze MPGs out ) but i would recommend doing things like a full exhaust from the headers back, cold air intake, throttle body spacer, plugs and wires...things along that line, will increase you fuel mileage and give you a little extra kick if you ever need it.

 

The CAI, TBS, and exhaust would certainly increase your MPG. But what is funny is that in all reality, you'll maintain the same MPG or decrease, because with the added power, it is hard to keep your foot off the pedal. Just drive like a Granny and you should be good to go.

 

If you drive at 60 you will get great milage. I average 26.1 (even before the mods).

 

don't forget the basics like properly inflated tires and aCLEAN after market filter. low temp thermostats too. i think everything else was covered.

 

I have been searching exaust and intake but all show only 4.8 and 5.3 applications. none for 4.3. I have found the tb spacer but that is it. I did install a K&N replacement filter. I would like to find a single exit performance exaust and a high flow intake. Any ideas?
Also you guys mentioned plugs and wires. What do you recommend? I was into mid 90s caprices and impalas with the LT1 and it came from the factory with a 180 thermostat. Is this not the case with the 4.3?
And is there headers, underdrive pulleysavailible?
As soon as I get some mods done I will get the pcm reprogramed by PCMperformance.com. They did my 95 cadillac fleetwood and shaved 4 tenths off my 1/4 mile times.

Bill

 

the 4.3 has like a 200 or 210 in it. I think thats what they said a few posts ago. I put the 180 in my 4.3 and it was noticeable with gas and power.

 

Impaladakid, underdrive pulley's will certainly help you save gas, and it will give you maybe 10 horsepower. What year is your truck by the way?

 

It is an 03

Bill