Mods to improve gas mileage?

I have found that the Auto is actually better for gas mileage. I had an 05 v6 6spd 4x4 access cab and averaged 19 mpg. I have a 2012 v6 auto 4x4 access cab and average 22.1 mpg with best tank at 23.9 mpg. You can get good mileage if your'e will to drive 65-70 on the highway and keep the rpms low around town. Check my fuelly.com for details.

 

You'll get better mpg in town pumping a clutch if you know what you're doing.

EPA says

5-lug
auto 19/24/21 effective highway gearing 2.54
stick 21/15/22 2.68

4x4
auto 18/21/19 2.55
stick 18/20/19 2.91

 

i figured as much on the in-town. some people have been telling me that the auto is actually better on the 5lug, guess not.

my friend at work (JL85) has a newer 6cyl auto 4x4 and says he has dropped about 5mpg from his 4x4 access cab stick (same commute/driving)

 

looked at your fuelly, you don't have your old truck on there?
you must drive very careful around town?

 

Ya, mine is fine. Rerouted the cable today so it is now permanently installed above the mirror.

For some reason, last night when I first plugged it in I waited forever and when I started the truck it kicked right in and connected.
Today, I had only left it plugged in for a minute or two while I put the A-pillar back on and it went dark and locked up when I started the truck.

 

So at this point I am convinced fuel line heater would improve mileage. My truck gets different mileage on the same fuel, on the same trip but at different temps. So I tired clipping copper heat-sink to fuel line to soak heat from headers. You guys don't want to know what I got in mileage. Now I need something safe and permanent before winter.

 

Actually hot air is good for winter. Remember the older engines with the valved intake tubes that would draw intake air from the around the exhaust manifold when the engine was cold? Kinda the same principle (though that was probably for emissions).

When air intake temps drop below 40 the mileage starts to take a pretty big dump. In the winter time I take the air elbow off and once the t-stat opens and the IAT rises from freezing to 60+F the inst. mpg reading on the UG will jump an easy 4 mpg in about 2 minutes.

I put the elbow back on just for kicks in the middle of winter and after 2 days of watching it drink fuel - and take forever and a half to warm up - I couldn't take it anymore. It came back off.

Hot air kills ignition advance when it's hot outside so it seems better mileage-wise to have the elbow in then, but even then it's not that big of a difference. Cruising isn't affected much but anytime the truck needed accelerating the avg mpg would bomb out more than usual. It just doesn't make good power with IATs over 120F (duh!).

Rule of thumb, if the air elbow is off and you don't have a grill block, IAT stays around 30-35F above ambient if moving. With the block, it's more like 35-40F. In stop&go it'll spike to +50-60 sometimes so keep that in mind if that's in your travel plans.

Thankfully unlike many vehicles it's only a 3 minute change from one to the other.

 

Not hot air, hot fuel. Since more ethanol is added to fuel it seems its mileage in winter completely suffers. It seems around 50F-60F is the breaking point. Once it drops below that temp fuel mileage goes to drain. Having problems with my Furnace in winters due to oil tank outside I had feeling Our trucks are having the same issue. So for $hits and giggles I just mounted computer CPU heat sink to fuel line (Yes it was one of those days) in such a way that gets heat from exhaust. That thing clocked best mileage I had ever seen. Stupid ethanol
Disclaimer: Now I strongly advise against doing the same with out knowing what you doing, and I take no responsibility if anybody tries and blows himself up.

 

Just thought I'd throw out there what I had done that actually yielded better mileage in the cold, just in case you don't have any success with the warm fuel plan. Maybe it's something else for you to try in tandem. Either way, warm air or warm fuel, it's to help that cold stuff atomize. Ditto, stupid ethanol.

 

The problem with playing with temperatures is the system is (hopefully) running in closed loop and compensates.
Cold fuel is more dense, and the computer would normally lean the mixture, but with cold fuel normally comes cold air, so they balance and you end up with effectively more air and more fuel per intake stroke.

Likewise, heating the fuel, without also warming the air, will lean the mixture... until the computer realizes that it's running lean... then it fattens it up.

But warm air, like high altitude are, is less dense, so the computer leans out... less power, but improved MPG if you don't try to draw full power from it.

This is something that we didn't enjoy with carbs... they ended up running slobbering rich at altitude and both power and economy sucked. By comparison, my bike normally gets about 35 here in LA.
Ran a tank in the mountains of Utah from Bryce Canyon up through Loa and back down to I-15... I pulled 55mpg on that tank, and that tank was "surrounded" by tanks at the normal 35, so it wasn't a matter of underfilling.
But 90% of that tank was above 6000ft.

 

Knowing BMW they will charge you for the wind you use.

 

2015 Tacoma v6 auto, lifter 4 inches running 33x12.50x20. I average 13mpg, I'd love to see 17-18

 

2013 TRD sport 4wd, and I get about 19.5 in the winter so far (got it a few months ago)and 20.5 in the summer.

For me I attribute the difference is due to me warming the truck up for a little bit when it is cold and the winter mix of fuel.

FYI: I keep my tires at 32psi as well and I have seen a small dip when they are at the recommended 29psi. Oh and I also run premium fuel because the truck feels more peppy with it to me… there is also a little bit of a mpg increase for me with premium…

I also changed my gear oil to 75-90 amsoil so that may have helped as well… didn’t do any real testing though.

 

I’m getting 20-23 in my 4.0 v6 manual 4x4. And using Lucas oil upper cylinder lubricant

 

Are you saving money running premium?

 

No it cost a little more for premium (about 5 bux per 21 gallons given the price difference of 87 vs 93 in my area and my mileage difference ).

I’m ok with that for the way the vehicle drives. I do wonder if getting those 3 degree cam gears would help with that for running 87 octane. From what I understand the trucks don’t have egr so some of the exhaust comes back into the cylinder which heats up the chamber. So I think those cam gears would help with the peppiness for 87 octane.

I am just talking out loud without any true real word experience so someone that has installed them might chime in with their observations.

Of course you may not be worried about the responsiveness of the truck on 87.

 

I once had a '79 Ford F150 4x4 with a 400 ci. About 10 MPG if I was lucky, I didn't keep it long. I can't say I'm really happy with my 17/18 mpg lifetime average, I can live with it knowing it's a 4x4.

 

Don't go over 65 for a month and check the difference. Leave five minutes early and let people pass you. Let them pay more for gas.

 

I would wager with ^ you’ll see 20/21 mpg

 

So the only way to increase mpg is by going slow.