Boosting fuel economy

[druid]

I know all about driving habits, but what can I do to my 4.0L 4X4 to maximize fuel economy without sacrificing performance TOO much?

One place I'm looking is tires. I now have BFG A/T KO's that have quite an aggressive tread. Would I get noticeable improvement if I went to, say, Michelin LTX A/T's?

Another is exhaust: a nice 2 1/4" Cat-back would be easy to put in - any help on fuel economy, practically? (I did it with my 4-cyl Nissan - I didn't see any improvement in the City, but maybe .5 km/L hwy...) I also added a K&N air filter, but I don't think it made a noticeable difference.

Oh, and obviously keeping the engine in tune, proper tire pressure, etc.

Any other suggestions?
druid

 

[Beanmachine7000]

Buy another car...

 

[AllanD]

I know all about driving habits, but what can I do to my 4.0L 4X4 to maximize fuel economy without sacrificing performance TOO much?

One place I'm looking is tires. I now have BFG A/T KO's that have quite an aggressive tread. Would I get noticeable improvement if I went to, say, Michelin LTX A/T's?

Another is exhaust: a nice 2 1/4" Cat-back would be easy to put in - any help on fuel economy, practically? (I did it with my 4-cyl Nissan - I didn't see any improvement in the City, but maybe .5 km/L hwy...) I also added a K&N air filter, but I don't think it made a noticeable difference.

Oh, and obviously keeping the engine in tune, proper tire pressure, etc.

Any other suggestions?
druid

a K&N doesn't do spit.

a bigger exhaust is unlikely to really do anything.

Replacing the K/O's? running them at higher pressure WILL reduce
rolling resistance.

"Driving technique" is most of it, but it isn't necissarily light throttle that saves gas.... it's "energy management"

Remember that every time you use the brakes you've just turned kinetic energy into heat, kinetic energy that you spent gas to create and will spend more gas to generate again.

High rates of acceleration don't necissarily burn more gas than light acceleration, but REPEATED hard acceleration (like from traffic light
to traffic light) does burn more fuel.

what really screws you up is sitting stationary, when the engine is running and you aren't moving you are getting ZERO MPG

I plan much of my driving to pass through intersections that tend to be "favorable" to my direction of travel or those that have no traffic
lights or stop signs on my route.

OR I travel at times where there is less traffic to slow my trip

Sometimes I drive around a hill (even if it's a couple miles out of my way)
rather than over...

On highway trips I tend to "tuck in" behind a Semi and Draft him...

If you are patient you can usually find a real "Rabbit" to follow

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[06RangerXLT]

i have bfg at ko's. run em at 40 psi and you will get just as much mileage as any other tire. get a soft tonneau cover, keep the truck empty and get a fram air filter. K&N are like chicken wire. they dont filter shit and they are over priced.

 

[Mike Tonon]

Should the tires be at 40 front and back? Or around 42 front, 40 back? I have a drop in K&N filter, I really would prefer not to replace it. Trying to save money here. I also took that tube plastic piece out of my air box and cut a hole near the front passenger side corner to improve air flow. What about port matching the intakes? Are there any flaws that should be modified out on the newer 4.0l's or Rangers for that matter? thanks

 

[Beanmachine7000]

Should the tires be at 40 front and back? Or around 42 front, 40 back? I have a drop in K&N filter, I really would prefer not to replace it. Trying to save money here. I also took that tube plastic piece out of my air box and cut a hole near the front passenger side corner to improve air flow. What about port matching the intakes? Are there any flaws that should be modified out on the newer 4.0l's or Rangers for that matter? thanks

Whatever feels comfortable to you really... You might run less in the rear unless you haul all the time... Less weight back there... Honestly, the biggest thing to help fuel economy is your driving... These motors are pretty much tuned from the factory to get the best possible fuel economy...

 

[Bob Ayers]

a K&N doesn't do spit.

a bigger exhaust is unlikely to really do anything.

Replacing the K/O's? running them at higher pressure WILL reduce
rolling resistance.

"Driving technique" is most of it, but it isn't necissarily light throttle that saves gas.... it's "energy management"

Remember that every time you use the brakes you've just turned kinetic energy into heat, kinetic energy that you spent gas to create and will spend more gas to generate again.

High rates of acceleration don't necissarily burn more gas than light acceleration, but REPEATED hard acceleration (like from traffic light
to traffic light) does burn more fuel.

what really screws you up is sitting stationary, when the engine is running and you aren't moving you are getting ZERO MPG

I plan much of my driving to pass through intersections that tend to be "favorable" to my direction of travel or those that have no traffic
lights or stop signs on my route.

OR I travel at times where there is less traffic to slow my trip

Sometimes I drive around a hill (even if it's a couple miles out of my way)
rather than over...

On highway trips I tend to "tuck in" behind a Semi and Draft him...

If you are patient you can usually find a real "Rabbit" to follow

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+1

 

[JohnnyO]

I put a Gibson cat-back on my Sport Trac and picked up 3 mpg on the highway. City mpg is no different. I also run Mobil 1 0w-30 Fuel Economy Formula oil and replaced the t-case lube with Mobil 1 ATF, FWIW. I also have a K&N air filter (Pep Boys had a coupon) but I've had them on two of my trucks and they didn't make any difference in anything. Less aggressive tires will make a difference.
The best bang for the buck is with a cat-back exhaust (as per Jim Allen), next would be a tuner like an XCal II but at that point you will have spent about $600, which will buy a lot of gas.

 

[Mike Tonon]

I put a Gibson cat-back on my Sport Trac and picked up 3 mpg on the highway. City mpg is no different. I also run Mobil 1 0w-30 Fuel Economy Formula oil and replaced the t-case lube with Mobil 1 ATF, FWIW. I also have a K&N air filter (Pep Boys had a coupon) but I've had them on two of my trucks and they didn't make any difference in anything. Less aggressive tires will make a difference.
The best bang for the buck is with a cat-back exhaust (as per Jim Allen), next would be a tuner like an XCal II but at that point you will have spent about $600, which will buy a lot of gas.

So when my exhaust rots out, its probably worth putting in a catback then. What exactly is a catback?

 

[JohnnyO]

So when my exhaust rots out, its probably worth putting in a catback then. What exactly is a catback?

A lower restriction (and louder) exhaust that bolts on behind the the catalytic converter so it is emissions-legal. I have a Gibson system on my Sport Trac.
The factory exhaust is stainless steel and there is a good chance the rest of your truck will rot away before the exhaust does. I cut the OE exhaust off of a 3 month old Sport Trac that I lease, but that's me.
I figured it would pay for itself with what I'd save in gas over 3 years, and that has turned out to be correct. Besides, now I'm probably going to buy it when the lease is up because they're not making Sport Tracs any more.