About my exhaust

[02EBEX]

all i have done is a 50 series delta flow muffler. Is there any thing else i can do that'll help my gas mileage.
its just a flow master muffler with everything else stock
any ideas would be great!!!!

 

[NENC Explorer]

Tune Up, Keep your oil changed on the dot every 3k, KN filter, keep your RPM's to less than 2600 at all times (4.0), I switched to mid grade from regular and got a decent bump in mileage (.5 miles to the gallon) according to my math and the truck.

I would say a better flowing exhaust and headers would be another good way to get better mileage, but for the money it wont show you the improvements you want.


Do what I did, buy a car.... (Trucks a toy now)

-Jeff

 

[CALDWELL]

1. I would suggest looking into a K&N Intake or KKM or similar, this will allow the engine to inhale more air, which will give you a bump in HP/TQ as well as better MPG ( est. 1 to 2 miles increase ). also it will make the muffler sound better...

* the K&N intake on an 03 X dyno'd ( + 7.5 HP ) on K&N's website...

2. Another suggestion would be remove the exhaust resonator just before the muffler, this will free the exhaust up some more, if you havent already removed it...

* may sound silly but, cut off the tail pipe where it makes the final turn to run straight out the back. then have a 45 degree exhaust exit. It's just one less bend in the exhaust which means better flow...

3. Run Synthetic oil, promotes smoother running engine...

4. bottle of fuel system cleaner once a month doesnt hurt...

5. try running 89 octane over 87, i am and it make a hell of a difference...

6. run larger exhaust piping ( 2.5'' pipe )...

7. proper tire pressure...

8. Change your transmission and center diff fluid...

9. tune from james to adjust for the larger tires...


** I have done everything on this list with the exception of # 9. And it has made a difference in performance, as well as MPG's

 

[fr0st m0nkey]

What kind of mileage are you pulling with all that Caldwell? I drive relatively aggressively city/freeway mixed and pull 16-17.

 

[BajaXplorer]

I found with my MAC exhaust (2.5") its killed all my low end ( which is where all the power is on a 4L Explorer is) Im wishing for my old stock exhaust back...

 

[CALDWELL]

I do 90% of my driving in stop and go traffic...

when i had My Red X I was getting roughly 15 to 16 MPG ( in town )

I had the following done to it...

K&N Intake / 2.5'' FlowMaster CBE / trans fluid change / fuel system cleaner / 87 Octane / Non Synthetic Oil

now with my Silver X im getting about 15 MPG ( in town )

I have the following done to it...

K&N Airbox Mod / Magnaflow Muffler / fuel system cleaner / 89 octane / Non Synthetic Oil

* i havent made the switch to Synthetic yet with my new X, but will on the next oil change. Im hoping to see a small gain by making the switch. also i would see more mpg gains if i run 2.5'' pipe instead of the factory 2.25''. i wanted to see how well the muffler would perform on its own. i may upgrade to 2.5'' pipe later on, but im happy for the time being. Also prob ably in the middle of the summer i will have the transmission and diff flushed with fresh fluids


BAJAXPLORER - yes you lost low end TQ, but i bet your X pulls like a **** even well into the top end ? with the K&N INTAKE, and 2.5'' EXHAUST my X pulled pretty hard thru the top end

 

[BajaXplorer]

CALDWELL,
you are correct- top end is great pulls well but I dont usually drive in the 38-4800 rpm range, most driving is at 22-2400 rpm in 5th gear on the freeway. so even though yes I technically get better freeway mileage, I do 90% of my driving in town, and thats where id like to have the mileage. Its a give/take situation with the exhasut. It probably would have been better for me to cut out the bulky stock muffler and weld in a replacement one, live and learn I guess..the wallet is lighter about $250- but it works decent, fit sucks on the MAC- someday I will get a replacement.

 

[CALDWELL]

thats what its all about fella, trial and error...