Trying to get my MPG back...

[crawler#976]

We're heading out in June for a 15 or 16 day vacation to the Northwest via the Oregon Coast to the Seattle area. With gas prices climbing, I've "de-modded" the Taco attempting to regain a few MPG. I estimate the trip to be about 4500 miles long.

Started checking mileage a few months ago- it had averaged 16.3 MPG. I don't do jack rabbit starts from lights, nor do I speed, and I use cruise control whenever possible. The fuel cost at 16.3 MPG is roughly $1035.00 @ $3.75 a gallon. If I can pick up 2.5 MPG, it drops to $897.00.

Wind resistance -
I've already removed the roof rack - picked up almost 1.0 MPG
Removing the rack ment the spare had to be relocated under the bed, so I had to have the custom exhaust rerouted. The hi-lift and shovel were moved to the inside of the tailgate - don't know where to put the spare gas yet...

Tires -
When I put on the new 31/10.5-15 MT/R's the MPG dropped almost 1.6 MPG. I've purchased a used stock alloy rim from an auto recycler, and by using my new A/T spare and buying a new tire to match, hope to get half that 1.6 MPG back. I'll run the A/T's up front. They won't be mounted until the week prior to our departure when I get the front MT/R's balanced and rotated to the rear. I plan on running the air pressure at 35 PSI vs the current 28 to firm up the tires a little.

Fluids -
Drained and refilled rear axle and transfercase with synthetic 75/90W.
Had the tranny fluid exchanged to remove all the old fluid vs just a drail and refill. Will be switching to synthetic 5/30 motor oil jsut prior to leaving.

The K&N airfilter has been cleaned and lightly oiled.

I've also plan to wash and wax the truck prior to leaving to improve airflow - maybe it will help, maybe not...

Any other tips/hint's???

Mark

 

[slooowr6]

What speed do you cruise at? At 63-65mph give me the best mpg. Depends on how much you are carrying you may need more psi in the tire. On my 06 Tacoma with close 1000lbs in the truck bed I need to air up to 40PSI, this is for stock P rated tire not sure what I need to run when I switch to LT rated tire. I get around 18mpg on freeway.

 

[crawler#976]

Currently planning on a DED (that's Dirt Every Day) trip with the exception of two long days on the interstates. The majority of each day's travel will be on local highways at the legal limit, and we'll get about 30 to 60 miles of unpaved sightseeing in.

To keep the MT/R's wearing flat, I've found that 28 PSI works well for my Taco.

 

[Scott Brady]

Won't you end up spending so much time and money (new tires, balancing, etc.) that it will negate the savings?

 

[hoser]

You can install UV film on all the windows including clear UV film on the windshield. Cuts down on AC usage. =)

 

[pwc]

For this one trip those new tires up front will get you back about $48 over 4500 miles at $3.75/gallon.
Each single MPG you gain gets you about $60 less in fuel costs. For the effort, I'm sure you can find otherways to save $60 on a 4500 mile roadtrip that are easier. If you make $20/hr (or value your time at that), did it take you more than 3 hours to find the spare rim, buy a second tire, get it mounted and ballanced? THen throw in the cost of the rim and tire. then throw in the cost of the fuel you used while picking up the rim and driving to the tire store. Now granted, maybe you were already going to the tire store so you don't completely count that cost.

If you're only looking at saving money, then it should be pretty easy to ballance most decisions against how much you value your time.

 

[slooowr6]

Currently planning on a DED (that's Dirt Every Day) trip with the exception of two long days on the interstates. The majority of each day's travel will be on local highways at the legal limit, and we'll get about 30 to 60 miles of unpaved sightseeing in.

To keep the MT/R's wearing flat, I've found that 28 PSI works well for my Taco.

I see, on local high way and dirt I think you have done all you can for mpg, my trip in Death Valley to Racetrack on dirt road I average 8-9mpg. Like other said, if just for this one trip then it's a moot point.

 

[chet]

seems like alot of work for $140 savings....

 

[crawler#976]

This is going to be a long term solution - I don't see fuel costs coming down soon. If I can justify the cost over a single trip, by the end of the year and 20,000 miles later, I should be coming out ahead...

 

[slooowr6]

This is going to be a long term solution - I don't see fuel costs coming down soon. If I can justify the cost over a single trip, by the end of the year and 20,000 miles later, I should be coming out ahead...

Also you'll have fewer fuel stops and longer range per tank.

 

[Grim Reaper]

Tires -
When I put on the new 31/10.5-15 MT/R's the MPG dropped almost 1.6 MPG. I've purchased a used stock alloy rim from an auto recycler, and by using my new A/T spare and buying a new tire to match, hope to get half that 1.6 MPG back. I'll run the A/T's up front. They won't be mounted until the week prior to our departure when I get the front MT/R's balanced and rotated to the rear. I plan on running the air pressure at 35 PSI vs the current 28 to firm up the tires a little.

Any other tips/hint's???

Mark

Are the tires the same height as stock? taller tires makes the odometer run slow

 

[crawler#976]

GPS indicates I'm running very close to the same MPH as I was with the BFG M/T's - 65 MPH on the speedometer shows 63 MPH on the Lowrance 3500C. The softer compound and heavier tire carcass of the MT/R's suck up gas. We noticed the same thing on the '05 Taco, and I believe BajaTaco reported the same thing when he switched from A/T's to MT/R's a couple years ago.

 

[DaveInDenver]

Are the tires the same height as stock? taller tires makes the odometer run slow

That's true. You can get an instant 6% "increase" in mileage by going down one size in tires. That is, of course, if you just read the miles and don't do the mental mathematics to correct the odometer. I went from 19 MPG on 30" tires and 4.10 gears (~12% undergeared) to 25 MPG with 33" tires and 5.29 gears (~10% overgeared). Yeah, yeah, if you correct the odometer by the 10% it's off, I'm only really getting about 21 MPG, but it does feel nice when the odometer shows 215 miles on half a tank of gas (about 9 gallons), even if I really only went 195. Doesn't help with your real mileage problem, it's just a feel good. Well, actually, it does sort of help to note that tire size and gearing to put your engine right in it's happy power band spot will help your mileage. I did see an actual 2 or 3 MPG increase in real (i.e. odometer corrected) mileage because with 5.29 gears my little 22R-E was happier hauling the weight of my truck. I went from 30x9.50 to 33x9.50 tires, so my section width did not increase and my tire patch didn't grow a whole lot. But my experience is not in sync with what the prevailing wisdom was, that low gears ruin mileage. They do if you assume a very high cruising speed, but from zero to about 65 MPH, having Power Wagon gearing seems to have actually increased my mileage, even if my top speed is only 85 MPH and my cruising speed is 70 MPH.

 

[Scott Brady]

I also gained 2 mpg with the switch to 5.29's

I just need to install some AT style 255/85's. Sure with BFG made some.

 

[Kilroy]

See thread about Scan Gauge II. I've found some very interesting things about the milage I'm getting while keeping an eye on MPG guage.