My quest for 30 MPG - Ford Explorer Gas Mileage Tips

[chairwolf]

Just found this thread and wanted to input. My 99 limited 4X4 4.0 sohc is now getting 30 average mpg on the highway. I changed the 4.10 gears to 3.73 and use 5w30. still has plenty of power, and by the way, my engine has over 320,000 miles!

Wow! What other mods have you done?

 

[EX-SV]

I'm thinking about 2013 Ford Escape 1.6L turbo, in the quest for 30mpg (highway).

My V8 6speed Explorer gets 19-20mpg at 75-80, 22mpg at 65-70 (highway).

 

[Birdy]

No other mods, thats at 60-65 mph. The guy I got it from was meticulous about changing the oil every 2000 miles, probably why it's still running like new.

 

[Texan01]

My well worn 95 with 293,000 on the clock has been getting a consistent 24mpg , and in the past has gotten as high as 29, so Al's right on the money.

mine has zero modifications to it, although now the heads have been shaved a bit to compensate for warpage.

Mine's an OHV so it's not quite as efficient as the SOHCs are.

 

[masospaghetti]

Not to resurrect an old thread..but...I was reading through this and something doesn't seem quite right.

A large number of folks keep claiming that the "SOHC motor is far more efficient than the OHV". I have a hard time believing that. The EPA ratings for the OHV motor are actually higher than the SOHC, and the SOHC has three or four timing chains (optional balance shaft chain) to spin, thus a lot of rotational loss. The OHV has a single chain.

Even ignoring EPA ratings, the SOHC has a slightly higher compression ratio (9.4 compared to 9.0, IIRC) but that wouldn't yield 20-30% improvements in fuel economy. Maybe a couple percent, but I think this would be offset by rotating losses in the valvetrain.

I had a 2000 Sport with the OHV, 5-speed manual, 3.27 gears, 2WD, 35 psi tires, synthetic oils all throughout, custom lower air dam, and SCT tune. Basically an Explorer set up to get good mileage. I could get 23-24 mpg on the highway at 65 mph, which i felt was quite good. 30+ mpg with a heavier 4 door, automatic, 3.55 gears just doesn't seem possible.

 

[r37ribution]

Not to resurrect an old thread..but...I was reading through this and something doesn't seem quite right.

A large number of folks keep claiming that the "SOHC motor is far more efficient than the OHV". I have a hard time believing that. The EPA ratings for the OHV motor are actually higher than the SOHC, and the SOHC has three or four timing chains (optional balance shaft chain) to spin, thus a lot of rotational loss. The OHV has a single chain.

Even ignoring EPA ratings, the SOHC has a slightly higher compression ratio (9.4 compared to 9.0, IIRC) but that wouldn't yield 20-30% improvements in fuel economy. Maybe a couple percent, but I think this would be offset by rotating losses in the valvetrain.

I had a 2000 Sport with the OHV, 5-speed manual, 3.27 gears, 2WD, 35 psi tires, synthetic oils all throughout, custom lower air dam, and SCT tune. Basically an Explorer set up to get good mileage. I could get 23-24 mpg on the highway at 65 mph, which i felt was quite good. 30+ mpg with a heavier 4 door, automatic, 3.55 gears just doesn't seem possible.

It has a lot to do with the efficiencies of the heads. I know for a fact that the OHV heads don't flow over 164 intake and 139 exhaust @ .500 lift in their stock form which is way more lift than the stock cam offers. The problem is inherant to the design of the heads. There is a sharp bend, the shape of the ports are huge, etc. I had a very experienced porter work on these heads for days and the most he could get the intake side up to was 184 cfm but once he got it that high the lower lift numbers started to drop off. Most people on Ranger Power Sports will tell you not to touch the intake port because usually you will make flow worse.

After all that I decided the lack of availability of parts and the cost of them wasn't worth the power gains and moved to a 5.0 project.

 

[Rick]

Apples and oranges. Fuel efficiency and maximum flow @ .500 have nothing to do with one another. The stock OHV V6 makes very good torque at low RPMs which means you don't have to put your foot as deep into it to move the mass. Less throttle, less fuel.

 

[r37ribution]

Apples and oranges. Fuel efficiency and maximum flow @ .500 have nothing to do with one another. The stock OHV V6 makes very good torque at low RPMs which means you don't have to put your foot as deep into it to move the mass. Less throttle, less fuel.

Correct, efficiency doesn't have anything to do with max flow @ .500 but the problem is that the flow numbers are terrible throughout the entire lift range 100-500. We tested the flow @ 100,2,3,4 and 500 on the stock heads. This does pose a problem with efficiency - the faster you can get air in at the lower lift numbers the more power you produce with less effort (i.e. reving the engine up). A lot of porters only look at the high lift flow numbers as you pointed out. We tried to optimize all of them which is why we didn't go past 182 because the lower numbers started to fizzel out.

Again, the issue is with the design of the ports on the heads - you just can't get any substantial gains out of them. Just to give you an idea of how vastly better the head design is - the 4.0 SOHC can flow 220 on the intake with a good port job whereas the OHV maxes out at 182. The sharp bend on the intake port is like the restrictor plate on a nascar engine. Remember the bottom end on both engines is virtually the same and interchangible (only one way?) with minor modifications. If the blocks are the same then what do you have left that could possibly make one engine's efficiency so vastly better than the other - the heads.

To further illustrate my point, the stock OHV 4.0L engine had 160hp while the OHC 4.0L had simliar power to the 5.0L with still decent torque numbers and the upper half of the engine was the primary difference. blocks are almost identical.

 

[Glen4X4]

I've owned both sohc and ohv and in stock form in a stock truck, a 96 ohv compared to 00sohc, the sohc only had a 1mpg improvement over the ohv. Ohv: 20mpg, sohc:21mpg And this was me calculating the tank everytime I filled up which I did when the 96 was stock and when I had the 00. Rick is quite knowledgeable when it comes to engines and knows what he's talking about.

 

[r37ribution]

I've owned both sohc and ohv and in stock form in a stock truck, a 96 ohv compared to 00sohc, the sohc only had a 1mpg improvement over the ohv. Ohv: 20mpg, sohc:21mpg And this was me calculating the tank everytime I filled up which I did when the 96 was stock and when I had the 00. Rick is quite knowledgeable when it comes to engines and knows what he's talking about.

Producing more power with the same fuel consumption is by definition more efficient. With all due respect to Rick and yourself, I think that Al Dive proved in this 105 page thread that the 4.0L SOHC is more than capable of producing > 21mpg.

 

[Glen4X4]

Producing more power with the same fuel consumption is by definition more efficient. With all due respect to Rick and yourself, I think that Al Dive proved in this 105 page thread that the 4.0L SOHC is more than capable of producing > 21mpg.

No worries, not trying to argue, just stating results I've found with stock vs. Stock.you're right about the ohc being slightly more efficient with hp(its morning here, didn't give it a thought Al also not only did some modifications but also changed driving habbits which have some impact on fuel mileage.

 

[r37ribution]

No worries, not trying to argue, just stating results I've found with stock vs. Stock.you're right about the ohc being slightly more efficient with hp(its morning here, didn't give it a thought Al also not only did some modifications but also changed driving habbits which have some impact on fuel mileage.

Oh yes his driving habits would have been impossible for me to replicate. I have a lead foot!

btw sorry for using the condescenting "with all due respect" phrase =P meant no harm by it. I just re-read it and realized I hate it when people say it to me.

 

[girly4x4]

I live in a rural area drive about 40 miles a day to and from work in my 02 ex 4.0 complety stock 72000 miles reading,drive like a reg.joe best I can get is 14mpg what gives? what mods. to consider?

 

[©H®I$]

I get about 15mpg I think. I'm pretty sure the body lift and bigger tires aren't helping. But I did put on a Flowmaster 40 recently and I would like to say that helps a little. And my MAC intake just came in the mail today so that's soon to be placed in.

 

[©H®I$]

But comparing both the OHV Explorer and the SOHC Explorer, lets so both have the same exact lift, and both have the same size tire (Lets say 32's), would the SOHC have better mpg because it would have to work less to push the tires? Or would the two cars have still similar MPG's with the SOHC getting about 1 mile greater mileage?

 

[masospaghetti]

I would still argue that the OHV has a lower friction valvetrain with fewer rotating components, so it should be at least as fuel efficient as the SOHC in most cases.

Noted, I understand the OHV produces far less power because the heads do not flow well, but in a cruise condition (highway driving) the engine isn't making much power anyway - something in the range of 30-50 hp. I think my point is somewhat validated by the EPA tests showing the OHV being slightly more fuel efficient with the manual transmission, and the same with the automatic.

For 2000, the Explorer with the 4.0 OHV/5-speed was rated at 18/23. For 2001 with the 4.0 SOHC, it was rated at 17/22.

 

[bleedgiantsblue]

Help!

good job on hitting 30+mpgs i was just wondering if you have any tips to help me to get better mileage with my 1999 xlt 302 awd i understand i wont be able to get as good as you did but any tips to help me improve my mpg would be welcome

 

[doug625]

these vehicles really seem to vary in mileage, my 2002 4.0 gets 24mpg on the highway with no mods at all. I am thinking about getting true dual exhaust(spare tire will have to come inside) and going with a K&N setup just to see what happens with performance and/or mileage.

 

[fancyponies]

My 2000 Ford Explorer Eddie Bauer 4L SOHC has 294,958k.

My 2000 Ford Explorer Eddie Bauer 4L SOHC has 294,958k. Last year we replaced the transfer case for the 4WD due to operator dumbness - didnt know it had one, let alone needed oil! Has had new spark plugs, gets 5k oil changes with synthetic oil, got good mileage (12.4L per 100k) till recently - what now? It has gotten poorer and poorer mileage, till now it is 15.6L/100k - the check engine light comes on, the dash panel says to tighten the gas cap, the garage says there are no codes!?

I love this vehicle, have had it 4 years, never want to part with it. It has the switch on the dash to change from AWD to 4 low or 4 high. I put winter tires on after October and switch back in the spring. It carries 4 bales of hay and tows my utility trailer or a combine header wagon. It pulls my 2 horse trailer. It carries 4 passengers in comfort with lots of luggage. If I put the back seats down I can carry 6 bicycles. Last winter when everyone else was getting stuck in my long snowy driveway, it just walked in and out over the wreckage they made of the chewed-up ruts.

It has some rust under the trim panels by the back wheels, otherwise looks good.

Any suggestions? Did I mention this is the best farmers wife vehicle I have ever owned?

 

[WidgetTrac]

If the check engine light has been coming on, then i'm pretty sure there should be codes in the long-term memory. The stored codes can be cleared, then drive it some more and see what new codes come up.

If no codes come up, then either it's got nothing wrong with it, or you need to try a new mechanic, or the computer itself has gone bad and it just isn't sending codes anymore. The one in my '89 Mustang did that.

The "other" trouble is likely to be a bad sensor, or just the computer itself, unless it is overdue for spark plugs/wires, or filters or something.

To test the computer, you could try having your shop unplug a sensor and then see if it gives the appropriate error code.