Drivetrain loss may be a factor. How many rpm'* of slip does your Torque Converter have in OD with the cruise on?

10-12 rpm slip.

How about buying a four banger?? :P


This week was the first time I took my GA out on the open roads, racked up a nice 27 mpg with 90% highway, 10% city.

or get a 1993 SE Bonneville with the 2.84 gear ratio like me

DrugRunner never got the best mileage, and my 4 banger now gets around 30mpg hwy, or pretty close to 30. I wish it was better, but I guess it'* not that bad. I think city is 21-22...better than my Bonneville and Cutlass was, but I still seem to fill up a lot.

I'm betting you have one of the higher ratio transmissions.
My Park Ave Ultra has the 2.93:1 final drive and gets around 21mpg average, but I can easily see 33-36mpg on the interstate.

my k&n intake added 2.5 mpg in highway-highway comparison.

I have question how do you 33-36 on the interstate . Ithought park ave were heavy then bonnieville that seems I bit high. My bonnieville gets around26-28 now just depends on how much highway you drive. The are actual lot of factors that go into fuel milage high you live.How rought the the triieans (hills). How you drive. The most constat the speed the better off you are.

I get around 12mpg in town and can do over 35 on the highway.... I think it'* the car... I drive like a grandma....