A 90's Honda CRV might do 30mpg with a 5 spd. I guess my tracker is getting 28 mpg with no mods but me, it is the last of the small 4 cyl SUVs with real 4x4, if that appeals to you. 90's Kia sportages also have real 4x4 and 4 cyl motor from Mazda. I imagine it has the same efficiency as the tracker but its motor is peppier. Suzuki had an AWD Aerio and now the SX4 is AWD.
On paper 4x4 is better than AWD in low speed "not getting stuck in the rutted snow" manuevers but I've never played with an AWD car enough to say how much better 4x4 is.
Many parttime systems like the CRV require front wheel spin to bring in the back axle and then they become true 4x4 for a while, I believe all the toyota's have a manual choice between 2wd, AWD, and then locking the center dif for 4x4.
Ian
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