Expected MPG on a 1998 V8 AWD

[Xylene]

What kind of gas millage are people getting on the V8 AWD models of the explorers? I have a 1998 Explorer V8 AWD and I am consistently getting about 11-12mpg and have for years.

Any suggestions for me if this seems low?

 

[Harpua216]

i get around 13-15MPG on a 99 5.0 mountaineer AWD with 180+. its much better on the highway, but still noticeably poor.

going to change plugs and wires, differential fluids, transfer case fluids and finish up with front bearings. she purrs and has no idle issues, other than maybe cleaning the throttle body, not going top side yet.

When i bought her, the previous owner complained about poor gas MPH (like 9-10 MPH) and his mechanic couldnt figure it out. took some starter fluid and found two cracked elbows on some vacuum lines. since then i have considered my self lucky!!

 

[Xylene]

I recently replaced my coil packs, wires and spark plugs hoping to see a difference but it didn't appear to do much. Just highway driving I do get better gas millage. I haven't been able to validate it but I think that if I constantly keep the fuel tank above a half a tank and maybe even 3/4 of a tank I get even better gas mileage. I need to validate if it's true.

 

[Harpua216]

I recently replaced my coil packs, wires and spark plugs hoping to see a difference but it didn't appear to do much. Just highway driving I do get better gas millage. I haven't been able to validate it but I think that if I constantly keep the fuel tank above a half a tank and maybe even 3/4 of a tank I get even better gas mileage. I need to validate if it's true.

funny i have noticed and thought the same thing about keeping the tank on the full side. I also think that the tank is playing mind games with me because my gauge is what you would consider to be "free flowing" mean it likes to jump around alot.

What I have been noticing recently, after the 180K mark, is there there was a bunch of friction around the suspension and the wheels that maybe shouldnt be there. after doing the control arms and shocks she feels like she is at least working less lately.

 

[koda2000]

We have four Gen II V8's in the family and the three 2WD's get anywhere from 15-17 around town and as much as 21-22 hwy. The AWD does a bit worse (I assume due to the extra weight). The best I've ever seen on my '01 EB was 23 hwy (flat roads, cool weather, speed around 55 on cruise control). Our two SOHC V6's get pretty much the ame MPG as the V8's. I live in a rural area with little traffic and some hills.

Where and how you drive have a lot to do with your fuel economy. If you drive in the mountains or in heavy stop-and-go traffic 13 MPG is not uncommon. When you're not moving your getting 0 MPG.

One big factor is poor performing O2 sensors. If you've got over 100K on your pre-cat O2 sensors, you should replace them. Check for a sooty tail pipe.

 

[SoNic67]

My 2001 V8, in busy traffic, gets 14-15MPG.
On highway gets 20MPG at 65MPH, but drops towards 17-18MPG at 85MPH (it's a flat faced brick, so air resistance is high at those speeds).
AC on or off makes very little difference on highway.
I have new hubs on front, new U-Joints and CV on the drive shafts, new tires, properly inflated, fluid changed in the differentials and transmission, new fuel pump (helped the mileage), new-ish spark plugs.

Stop and go traffic is not relevant because when stopped the MPG is zero...

 

[Harpua216]

We have four Gen II V8's in the family and the three 2WD's get anywhere from 15-17 around town and as much as 21-22 hwy. The AWD does a bit worse (I assume due to the extra weight). The best I've ever seen on my '01 EB was 23 hwy (flat roads, cool weather, speed around 55 on cruise control). Our two SOHC V6's get pretty much the ame MPG as the V8's. I live in a rural area with little traffic and some hills.

Where and how you drive have a lot to do with your fuel economy. If you drive in the mountains or in heavy stop-and-go traffic 13 MPG is not uncommon. When you're not moving your getting 0 MPG.

One big factor is poor performing O2 sensors. If you've got over 100K on your pre-cat O2 sensors, you should replace them. Check for a sooty tail pipe.

Makes alot of sense. My rear main had a slow leak onto my cat and O2 before i picked it up, and my muffler is rigged um, lets just say i happen to think it a thing of beauty and luckily you cant see it!!

I have a lean code to it and i know why, but my mileage predates the rear main problem. But against someone elses advice locally, i have already decided to change the exhaust cat back and get someone to fix some cracks. koda - do you have any advice or suggestions to make an efficient and inexpensive exhaust that removes the two regulators that will help with efficiency? I am tired of playing doctor. anyway I plan to settle the O2 during this.

my wifes 04 V6 AWD gets 12MPH in town. but she drives maybe 10 miles a day and her round trip to work is less than 3 miles. highest i had it was 13 on a 45 minute drive. rear bearings are shot, sway bushings toast, had 3 quarts overflow of ATF when i got her.. just starting to uncover whats going on. any help or tricks otherwise for an SOHC i would appreciate from anyone too

 

[Xylene]

We have four Gen II V8's in the family and the three 2WD's get anywhere from 15-17 around town and as much as 21-22 hwy. The AWD does a bit worse (I assume due to the extra weight). The best I've ever seen on my '01 EB was 23 hwy (flat roads, cool weather, speed around 55 on cruise control). Our two SOHC V6's get pretty much the ame MPG as the V8's. I live in a rural area with little traffic and some hills.

Where and how you drive have a lot to do with your fuel economy. If you drive in the mountains or in heavy stop-and-go traffic 13 MPG is not uncommon. When you're not moving your getting 0 MPG.

One big factor is poor performing O2 sensors. If you've got over 100K on your pre-cat O2 sensors, you should replace them. Check for a sooty tail pipe.

I haven't replaced any of my O2 sensors that I can remember. I have had them checked a few times and they all say reading within normal range. I kind of suspect that I have a manifold leak. I keep getting codes about my cat not reading correctly. I figure something up from the cat isn't doing it's job and the cat is paying for it.

 

[koda2000]

I haven't replaced any of my O2 sensors that I can remember. I have had them checked a few times and they all say reading within normal range. I kind of suspect that I have a manifold leak. I keep getting codes about my cat not reading correctly. I figure something up from the cat isn't doing it's job and the cat is paying for it.

FYI, I just drove my '01 RWD EB V8 3:73 gears to town and back (30 mile round trip w/several good sized hills). I reset the avr MPG before I left. It registered 18.9 MPG average. Along the way before the hills I saw it register over 20 MPG.

 

[1998Exp]

Your RWD makes me jealous! My '98 with the same gearing but AWD, consistently shows around 16.2 average on the message center. And, to make things worse, I 'calibrated' the message center and found out that it reads about 6% better than the real gas mileage. So the real mpg is about 15.5. Most of my driving is on the freeway, doing 60-70 MPH and scaling a 1000 ft hill. The truck used to do about 17 when it was younger, so I've been thinking of replacing the pre-cat sensors, but being driven less than 5000 miles a year and the recently decent gas prices, it doesn't seem to be worth the hassle.

FYI, I just drove my '01 RWD EB V8 3:73 gears to town and back (30 mile round trip w/several good sized hills). I reset the avr MPG before I left. It registered 18.9 MPG average. Along the way before the hills I saw it register over 20 MPG.

 

[Highflow50]

I get 20mpg with my 5.0 awd and I have 283k. Just keep up with routine maintenance and mobile 1 oil. I also have many mods but those should consume more gas.

 

[koda2000]

Your RWD makes me jealous! My '98 with the same gearing but AWD, consistently shows around 16.2 average on the message center. And, to make things worse, I 'calibrated' the message center and found out that it reads about 6% better than the real gas mileage. So the real mpg is about 15.5. Most of my driving is on the freeway, doing 60-70 MPH and scaling a 1000 ft hill. The truck used to do about 17 when it was younger, so I've been thinking of replacing the pre-cat sensors, but being driven less than 5000 miles a year and the recently decent gas prices, it doesn't seem to be worth the hassle.

For what it's worth, I've found my AWD gets about 2 MPG less than my RWD's.

 

[SWIGIN]

I find the same to be true.

I gained 1.7 mpg going from AWD to 4x4 in my 98 5.0 for what it's worth.

 

[intelisevil]

My '99 Mounty 5.0 AWD (3.73 diffs) with 273,000 miles gets 16-17 in combo driving. I recently took a 300 mile trip that was 80% freeway (not flat and straight) and my mileage was just over 21. I've had it for about 2.5 years and 30,000 miles. I've never seen less than 15 mpg on a tank.

Always hand calculated. The message center is 1-1.5 generous . . .

 

[1998Exp]

I am holding the original window sticker for my '98 AWD (3.73 axle). Along with the ridiculous $36,510 MSRP, it states in huge bold letters "CITY MPG: 14, HIGHWAY MPG: 18" When I bought this vehicle, with 35,000 miles, it accomplished 16.5-17 on the freeway. Now, at 163,000 it's about 1 MPG less. And no, I don't use heavy engine oil. I also change the plugs, wires, and other fluids regularly, and definitely don't have a lead foot. The torque converter locks/unlocks like it should, and except for a bit of whine from the rear differential there are no signs of anything wrong. Coolant temperature is nice and steady around 190F (verified with a sccanner). So what's going on here? I am assuming that the 1 MPG degradation is due to sluggish oxygen sensors, but no clue otherwise. Perhaps I got a Monday engine.
Incidentally, my 2004 RWD Crown Victoria (with a more modern 4.6L engine, identical transmission and less than half the miles on the ODO) gets about 20 MPG on the same freeway (vs. Ford's promised 23). Another Monday engine?

My '99 Mounty 5.0 AWD (3.73 diffs) with 273,000 miles gets 16-17 in combo driving. I recently took a 300 mile trip that was 80% freeway (not flat and straight) and my mileage was just over 21. I've had it for about 2.5 years and 30,000 miles. I've never seen less than 15 mpg on a tank.

Always hand calculated. The message center is 1-1.5 generous . . .

 

[Harpua216]

compression is also a factor of good gas MPG. Another thing to consider is friction against your wheels and suspension. I gained about 1.5 mph after diong shocks, ball joints, sways and think i can many get another 1.5 MPG replacing the hub assemblies and bearings. I just dont have access to a shop press so i am going to build one so i can do my 04 AWD.

can anyone explain the idea behind the "day" of the build. I am interested. thanks

 

[beach]

On my 2wd V8 stock, was about 15 city and 20-21 highway at 75-80 hand calc'd (good ol' flat sea level FL lol). With lift and 31s, mileage took a nosedive, thought it was different much at first but it's just a spare vehicle so wasn't driving it much. But now in city I'm lucky to get 12-13 and 16-18 highway . Computer reads 13 avg vs 16 before. Did a full tune up last year right down to bearings and new wires and plugs etc, rims are light weight procomp alloys. Don't care about gas mileage, but wonder if the tires are throwing the readings off being 31s.

 

[1998Exp]

On my 2wd V8 stock, was about 15 city and 20-21 highway at 75-80 hand calc'd (good ol' flat sea level FL lol). With lift and 31s, mileage took a nosedive, thought it was different much at first but it's just a spare vehicle so wasn't driving it much. But now in city I'm lucky to get 12-13 and 16-18 highway . Computer reads 13 avg vs 16 before. Did a full tune up last year right down to bearings and new wires and plugs etc, rims are light weight procomp alloys. Don't care about gas mileage, but wonder if the tires are throwing the readings off being 31s.

If your stock tires were 235/75, that's 28.9" diameter. Your 31s will cause a 7% error on the speedo/odo, but that's a far cry from the 20% degradation that you found.

 

[beach]

If your stock tires were 235/75, that's 28.9" diameter. Your 31s will cause a 7% error on the speedo/odo, but that's a far cry from the 20% degradation that you found.

Yeah thats what I thought from reading on here, that the lift and 31s wouldn't really make a difference. But its definitely noticeable, even the readout dropped to 13.1 avg vs 16.4. Asked a few people on here and they said they saw a big difference in gas mileage after going to 31s.... weird, thought it wouldn't really make a difference, especially with the lightweight alloys vs the heavy steelies most use.

 

[geosnooker2000]

I'm getting 21 when I drive real carefully, but I don't think we are on summertime blends just yet. I usually see 18 to 19 in the dead of summer, and for some reason, in the dead of winter as well... I have found the greatest difference to be due to low tire pressure.