Improving fuel economy.

[hatzic]

Good Day All
Not happy with the fuel economy of the 4L engine. My truck is an '09 4X4 with automatic trans., LS diff. and 3:55 gears. Went to all synthetic oil on the last change and that took me from 12L per 100 K to about 10.8 per 100; (Yes I'm in Canada) some improvement noted here. Next is to go to full synthetic (Royal Purple) oil in the rear end.
So the next item up for consideration.
What is the consensus of those of you who have installed the K&N FIPK in your 4L as it affects fuel consumption, all things being equal?
Last but not least is the performance chip route. Any experience with this in regards to fuel economy?
Thanks all for the input.

 

[JohnnyO]

You will get the best bang for your buck with a cat-back exhaust like a Gibson or Magnaflow or whatever.
A K&N FIPK won't make any difference because the stock intake isn't very restrictive to begin with. Just get a K&N drop-in, remove the silencer, and call it good.
Your truck already has full synthetic lube in the axle from the factory, although it doesn't hurt to change it every 30k or so.
I use Mobil 1 ATF in the transfer case. It is not hard to change yourself if you get a suction gun to fill it with.
A tuner is better than a chip because it can be customized to your truck. Should be the last mod you do because it can be set to optimize the mods you've done. Dudes at the Sport Trac site like the SCT tuner from Unleashed Tuning, ask for Torrie. I haven't tried it myself.

http://www.unleashedtuning.com/

My Sport Trac has the same engine, 3.73 gears, K&N, and Gibson exhaust. I will get 21-23 mpg on a level highway if I keep it to 65 mph. City mpg is no different than before, about 14.

The thing you have to look at is how long until the mods pay for themselves with what you save in gas? Exhaust = $360, had it on for 3.5 years, it's paid for itself. Tuner about $350, be another 2-3 years payoff if I got one. FIPK costs $230, payoff period = never.

 

[hatzic]

You will get the best bang for your buck with a cat-back exhaust like a Gibson or Magnaflow or whatever.
A K&N FIPK won't make any difference because the stock intake isn't very restrictive to begin with. Just get a K&N drop-in, remove the silencer, and call it good.
Your truck already has full synthetic lube in the axle from the factory, although it doesn't hurt to change it every 30k or so.
I use Mobil 1 ATF in the transfer case. It is not hard to change yourself if you get a suction gun to fill it with.
A tuner is better than a chip because it can be customized to your truck. Should be the last mod you do because it can be set to optimize the mods you've done. Dudes at the Sport Trac site like the SCT tuner from Unleashed Tuning, ask for Torrie. I haven't tried it myself.

http://www.unleashedtuning.com/

My Sport Trac has the same engine, 3.73 gears, K&N, and Gibson exhaust. I will get 21-23 mpg on a level highway if I keep it to 65 mph. City mpg is no different than before, about 14.

The thing you have to look at is how long until the mods pay for themselves with what you save in gas? Exhaust = $360, had it on for 3.5 years, it's paid for itself. Tuner about $350, be another 2-3 years payoff if I got one. FIPK costs $230, payoff period = never.

Appreciate the advice on this.
Where is the "silencer" located? Perhaps the more relevant question would be what is it?
Will look into the exhaust system in more detail.
Thanks again.