that's what i got out of my 98 grand cherokee with the 4.0. the 5.2's and 5.9's aren't much worse and are much better drive...if only i'd realized that beforehand.This is definitely an interesting read. 35mpg on Imperial gallons translates to roughly 28mpg. But 1200km on 70L of fuel translates to 40mpg! So maybe his calculations are inconsistent, but the original GC with the 4 liter gasoline six is known to get poor mileage, mid teens in mixed driving and you can squeeze 20 out of it on the highway (but only on the third Sunday of the month if Mars is in line with Jupiter and you flossed your teeth every day for the last year and Santa didn't catch you cheating on your 1040).
The GC owner is also converting his '99 Dakota with a 4-liter Isuzu diesel.