Gas mileage check

[CharlesHS]

The only modification that showed an immediate increase in gas mileage was to move from California to Florida.
I have tracked my gas mileage with almost all highway driving and there has been an 2 mpg increase during a 750 mile drive.

 

[JPHikr]

We get 15mpg on the road to town and back which is 40 miles one way.

There are no stoplights and two stop signs.

I drive at 55 on the cruise control.

Our W164 with the 5.0 V8 gets 20mpg on the same trip to town (55 mph on the Cruise control).

The differences is aerodynamics.

 

[Rooscooter]

My 05 Rubicon with the 6 speed ranges between 14 and 16 in hybrid driving. That's up from 12-13 when I bought it with 78K on it last year.

Maintenance that helped me: running a "top end" cleaner (Berryman Intake Valve and Combustion Chamber Cleaner) through the engine, replacing the plugs, replacing the O2 sensors and cleaning the entire throttle body and contributing parts.