As some of you may remember, I bought a '97 V-8 AWD last year. I really like the truck, it pulls my boat around like it isn't there. The downside has definately been the terrible mileage. It get's 13.5 towing and 13.8 empty. Everyone tells me it's the nature of the beast (AWD and all). Only problem is, I know guys that do a lot better. A friend with a 98 Mercury version of the same truck has pulled as high as 21 with his. I was just curious if anyone has found any new tricks to help these things be a little friendlier at the pump.

I've played with tire pressures, filters, and even scanned it and can't find anything that even makes a difference at all.

 

Don't know if this will help, but I had a pinion gear go bad in the rear-end. It started making noise and apparently had been going bad for some time. I can tell a real difference now. The only down-side is that now the pinion gear is new but the rest of the rear end has 158K miles on it so I'm getting some whine. (Don't you just hate it when your rear-end makes noise ) But the mileage has definately improved. I'll be pulling a boat this weekend so I'll see if the hiway mileage also shows an improvement.

 

Another item to consider would be the gear ratio. When we bought the Mountaineer, the Mercurys on the lot all had 3.55 gears, the Explorers were mostly 3.73. But 13.5 sounds low even with 3.73s, the Expedition we had did about that with the 5.4 and 3.73s.

 

I will be watching this thread. My wifes' 99 Ford EXPLORER EB AWD 5.0 gets only 11mpg's city driving. The truck only has about 85K. The DPFE sensor along with the EGR valve and solenoid are new. I know 11mpg's are low and I don' t even tow anything. Hopefully the changing of plugs and wires might bring it up a little.

 

I'm sure confused....we've had alot of posts saying the 5.0 gets equivalent mileage to the 4.0 SOHC. More power, same mileage.......

 

Perhaps I am one of the lucky ones. My 98 AWD 5.0 Mountaineer is getting 16-17 mpg around town and in rush hour freeway traffic. No special mileage improving gadgets have been added, 87 octane fuel, light to moderate acceleration. It seems like 13 mpg is way low, the worst mpg has been around 14 in very cold weather operation.

 

There does seem to be something fishy about these trucks. They either get 11-14 or 16-18. I'd sure like to figure out what the difference is. I filled her up today with a bottle of injector cleaner, new air filter, and cleaned the MAF sensor. Didn't notice any change on the way home.

Interesting about the Mercs possibly having a different ratio, I'll ask my buddie to double check his.

Hank, you may be on to something. I should go through the drivetrain and look for anything suspicious. I do want to change all the fluids down there before next month. I have a trip to Shasta Lake in June with the boat.

 

I don't know if you are having the ame problem as a friend of mine (and me for that matter), but are you having any problems with the torque converter taking a second to get going? Almost like it is leaking down and taking a second to fill up? A friend of mine with a 2000 AWD Saleen was having problems around town - not bad, but just slightly noticeable. He was in the 11-12 range in the city and 16 on the interstate. Finally narrowed it down to his torque converter. Replaced it and has been getting 15-17 in the city and 17-19 on the interstate. He has a lead foot on the highway, so I imagine he could do better than that if he drove right.

Mine gets around 11-13 around town, but is getting 18-21 on the interstate on long runs. And that is running at almost 400 horses. I can feel my torque converter starting to show its life (180,000 miles), but I'm waiting onit to fall so the 5-speed manual can go in. Gives me an excuse with the wife....

 

The converter seems normal as far as I can tell. The truck only has 71,000 miles on it. I did have to replace the front pinion seal after I bought it. It was leaking right on the exhaust pipe (brilliant idea there). Only time I get any funny sound is when I make a hard turn around a switchback style corner. It will let out a small whine, I figure that's just the AWD arguing with the limited slip. I think I'll change the trans and transfer case oils out next. There could be some gains in there I would think.

Another funny thing is you guys always mention city vs hiway miles. This thing gets almost the exact same no matter how or where I drive it. In the end this will probably turn out to be a clue, just not sure how yet.

 

Have you checked the fuel pressure? I'm wonder if the regulator isn't right. What plugs are you running in it?

 

No I haven't. It still has the factory plugs and wires also. Those are on my 'to do' list as well. What brands would be good to look for? It does seem a little doggy until the rpm comes up. I was reading in the manual this morning, it claims it has different plugs in 1 2 3 than the rest? First time I've heard of that!

 

Just use regular Ford wires and Autolite Double Platinum plugs. You will get the best results from them. A lot of people have run the Bosch plugs, and I have tried them, but I did not like them.

If you want a little better than stock wire, get the Taylors. Summit carries them. They have a little more of a pricetag, but they are made for more of a modification type setup.

Even running what I do, I still have stock wires on mine. Most of the aftermarkets are the same size.

 

I recently drove my 2000 X EB 5.0 AWD 3.73 from ohio to washington dc area for the weekend....against all the debates i've heard from everyone about K&N air filters...i bought and installed it before i left...from my home to the freeway steady crusing at 55..i averaged 24mpg....75-80 mph on the turnpike up and down the mountains i averaged 20-21...and coming home with my head in the wind i averaged 18-19... but i would say with steady 55-60 speeds i have definately noticed better mileage... any questions let me know...

gpyles

 

What's it get with a paper filter in it?

 

I gained about 1mpg around town..2-3 on the highway at 55-60 and 1mpg at 75-80mph