I have a 1991 Montero RS 3.0 AT 196k

I am getting crap for gas mileageà roughly 11mpg, not more than 250 miles
From a full tank.

My last Montero was a 90 w/ 3.0 AT with 189k on it and I was pushing
21-21mpg! That was mostly highway driving but I hardly think that is makes
A 10mpg difference.

Any thoughts?