I have owned my 94 351 for about 5 weeks now and I have gotten the following mileage: 14.3, 15.0, 15.30, 13.3, 16.7, 13.3. I got the 16.7 and 13.3 after my tune up. I put all new plugs, wires, rotor, and cap on. I also bored out my airbox w/30+ 1/2 holes and a K&N drop-in. I got a little better than this out of my 95 5.0 but the 351w has tons of low-end power. The mileage really varies with the weight of your right foot. I got my 13 mpq readings testing the power. Most of the time I drive like grandma to get mileage but it has plenty of reserve power when I need it. You really don't have to give it much juice off the line to keep up with traffic. I've heard that electric fans and underdrive pulleys can add 1+ mpg and I may try these.
1994 Black/Silver F150 XLT 4x4 Reg Cab / Short Bed, 3.55 LSD Front & Rear, 5.8L w/85k miles, K&N drop-in w/bored out airbox
Upgrade wish list: 31x10.5, Gibson exhaust, helper springs, SuperChip???, lights
I had a '95 F150 SC SB with the 351 and an automatic. I got about 14 to 15 around town and 17 to 18 on the freeway empty. I had plenty of power. after I lifted the truck and put 35's on it though it droped to about 15 on the freeway and 12 around town, but i still had plenty of power. plus the tow rating on the 351 with the AT is way higher then the 302 5 speed I belive mine was 7200 and the 302 5 speed was 3500. I am not sure about the 302 AT.
good luck it was a great truck I wish I would have been able to keep it.
Hi! I have a '93 XLT with 97K miles, standard cab and long wheelbase. With the 351, I can achieve about 15 to 17 miles per gallon if I stick to the interstate. City driving is a bit punishing at 10 to 12 MPG. I drive about 400 miles each week and use roughly 28 gallons of fuel equating to a lovely 14.5 MPG. Mind you, only 70% of these miles are interstate. I also have 31x10.5" tires and tend to stretch the throttle return springs on a regular basis. On a 3300 mile round trip to North Carolina last August, I attained about 16 MPG each way with a topper, stock tires and A/C in use.
The 302, according to many people, appears to get only marginally higher MPG (a difference of +1 or +2 MPG). For the 300, ditto. I have never driven either of the above for the purpose of obtaining fuel data, so I cannot guarantee those statements. What I can guarantee will be your satisfaction when the time comes to apply the "go pedal." If that '95 is a decent deal with a healthy 351W, I urge you not to hesitate in snatching it up. The F-150 chassis is hard enough to come by with that engine.
Regarding your concern for the 4x4 system, you should initially be looking for leaks from the transfer case / transmission mating area, and the front axle housing including its inner shaft seals. Be wary of dried axle joints on the front end, apparent when the steering wheel has difficulty re-centering itself from a turn. A leaking housing or shaft seal necessitates disassembly of the greater part of the front end to install a fresh one. The axle joints need only the hubs and rotors removed, I believe. Other than that, if both hubs lock in without difficulty and it operates quietly in 4HI and 4LO, you should have a pretty nice set-up.