I had a 90 Aerostar extended van years ago with the 3.0 XLT with dual air and automatic; it got 26mpg on hwy and 20 around town, I loved the mileage and it was a nice ride but it was lacking in power. I have a 4.0 engine in my 95 explorer and my 93 ranger, and in my wife's 02 Explorer, I would rather have the 4.0 any day and they run forever like the 3.0 and get 19 to 23 mpg city and hwy;( I like the older 4.0 pushrod the best) I did notice when I changed plugs from Bosch to Autolite my mileage dropped 2mpg in city and hwy; so I will go back to Bosch.

 

Do NOT use the Bosch. They do not work correctly on Fords or most other vehicles for that matter. The waste spark ignition the van has will eat Bosch plugs alive, I have seen the Bosch fail in such applications in as little as 5000 miles. In a vehicle thats as hard to access, you want to make sure you use plugs that last. Use the APP105 or APP104 or XP105 plugs. My guess on why your mileage dropped is you did not use one of those Autolite numbers.

 

Ok, I will check these out soon for my older 95' Explorer and the 93' Ranger.

 

I have a '94 with the 4.0 OHV and it still runs perfectly at 165K miles. It's a 4x4 can and a half on 31" tires and I get 16-18 MPG on average highway. In my experience the 4.0 is easy to work on, but seldom needs it. The big thing to watch for is the auto transmissions. I've heard about dozens of them failing, and I fear that mine is starting to go.

 

All transmissions will fail eventually, the A4LD and the later 4R44e, 4R55e, and 5R55e are all light duty transmissions, though later ones were better up until the PWM torque converter lockup was introduced on the 5R55e.

Even so, maintenance is key. Most people never think to change fluid or do any maintenance on the trans until it starts acting up. By then its usually too late.

The trans will eventually fail regardless of the engine, all the Ranger autos are one of the above designs. It s a moving mechanical thing, and regardless of who makes it, all of them have a finite lifespan.

 

I think the 5 speed really enhances what the 3.0 motor can do. Over the weekend I had a 1300 mile trip, It was mostly highway, but even at that the hills through the St. Louis area would bring big trucks down to 50mph. On my trip down with 400 pounds of stuff in the back of my newer to me 99 extended cab step side with 3:73 gears, and driving 65-75, I got 21 mpg, never a shift down except for gas stops. When I got to my destination I finally had a chance to put plugs in it. I went with SP500 Motorcraft fine wires. On my trip back with over 1000 lbs + and some stuff sticking up above the cab I got 23.8 mpg, still never had to shift down. With out a load I usually take off in 2nd and short shift 3rd to 5th. I hear people talk about the 3.slo but I don’t get it. In this form it does everything I can ask for a small truck. My limiting factor is usually traction, not power <O</O

 

I drove a '91 2wd 3.0 for 15 years and it was still running great with just under 320K on it when I overestimated its' deep water fording capabilities and drove it down a flooded road near a river. Nothing bad to say about the 3.0 from me. I currently drive a '98 4wd 4.0 and have over 223K with no problems to speak of. Unless you've got plans to keep the truck a long time or have a special purpose for it, I'd say either option would get you by til better times come along. Don't overthink it, buy what's most affordable.