I have got up to 37 mpg on the highway in my car. Only thing done to it (as far as I know) is a K&N intake.

 

I found that I get a few mpg better between 70 and 80 than I do around 60. 2300 RPM is about the ideal cruising RPM for a 3800.

 

I guess I need to try changing my plugs/wires. With my 05 3400 the most I've managed to get is right around 23-24 mostly highway. City I normally get 18-19. Only mods so far are l67 coils, exhaust, and fender-well intake (did help by about .5 mpg, give or take..)

I wonder if MPG is something that's effected by how the engine is broken in? Doesn't make sense that a bunch of people with the same car get such different results.

 

The drivetrain loss on these cars is about the same 20%, it's still really terrible.

 

I want to know how it's still 20% driveline loss. Was it that terribly made? General rule of thumb is 15% for manuals, 20-25% for RWD automatic, around 30% for FWD automatic, and around 40% for AWD.

 

It baffles me that 3800 owners are getting such high mpg's. I struggle to achieve 25mpg anymorw with my 3100.

 

Just goes to show how good of a design the 3800 was. Durable, efficient, powerful for a V6 of the era, especially in S/C form.

 

Indeed, i would just think with a smaller engine i should atleast be able to get a little bit closer. Normally you'd think the bigger engine would have less mpg than a smaller one

 

I'm not getting 30-40 mpg out of my 3800 either and it runs fine with no known problems. I'm at a loss.

 

I'm pretty shocked at some of the numbers myself. I mean to make it clear he is by no means doing over 65 or under 60. His car had NO tune and was a DD with a lot of in town driving. I thought possibly with some mods yes but the way he stomps on it and his in town burn outs combined with his other driving skills I thought it no way possible.