2002 Tacoma Gas Mileage

[Reece04]

I just did my first "road" trip in my 2002 Tacoma that I bought a few weeks ago. It is a 4x4 ext cab with the 3.4L. with the manual tranny, It has about 94K miles but is in really good condition, no leaks, no smells, noises, it was a very clean truck. anyway, we just did this trip and on the freeway, at 75 - 80 it was only getting about 17.5 miles per gallon.

I did put 265/75R16 tires on so they are about 1inch taller than stock, and they are BFG A/Ts. I am not real concerned about the mileage,(it beats my Suburban which gets 13 on the highway) I am just curious

what is everyone else averaging? I am planning on doing the Deck plate mod, will that help???

thanks for any input!

 

[TacoTraveler]

I drive that exact same year and model truck. I also recently did a road trip and I also drove 75-80 and I also got just at 17.5 on average.
I thought the deck plate in and out would make a difference so I tested by alternating between tanks. I did not notice a significant difference. I only noticed a sound difference when pushing the gas and passing someone, lol.
In town driving though I have noticed a difference. If I drive calmly it actually increases my mpg. If I drive harsh I get better mpg with it in. Either way it is a good thing to have in my opinion because I definately notice a power difference with it in and out.

But just remember to put the plate in any time you take your truck offroad.

 

[Hoosier 45]

We took a trip to the Outer Banks fo NC from Indiana, loaded with about 900 -1000 lbs. of people and gear. Driving 60 - 65 in an '03 DC we got 23 - 24.

 

[Rexsname]

If I keep it at 70 or less I can get 20mpg. faster than that....the mileage drops off considerably. These are not areodynamic beauties


REX

 

[dnellans]

2004 extra cab with 255/85

I get about 15mph in town and 19 on the highway with just my cap/normal stuff in the bed. I can get just over 20 on the highway if I drive conservatively.

putting a 3 bar roof rack on with a basket and a kayak, or towing a trailer with 2 dirtbikes, and my normal long weekend stuff in the back I'm lucky to get 16 on the highway, 14-15 is pretty normal.

I think you're in line with normal averages, I wouldn't worry about it. I've done deckplate/exhaust and measured the combo to be good for about 1MPG, not sure I would spend the money to do it again given the margin of error on measuring. The best thing you can do to improve mpg is drive slower!

 

[xcmountain80]

We took a trip to the Outer Banks fo NC from Indiana, loaded with about 900 -1000 lbs. of people and gear. Driving 60 - 65 in an '03 DC we got 23 - 24.

This is closer to what my brother was getting with his not so much the 19-20.

Aaron

 

[Martinjmpr]

Mine is just like yours except it's a 2004. I normally set the CC at 65 and on flat terrain I can average 21-22 on the highway. Mountain driving drops it to 20 or so.

Not sure if you have a shell but I do. I haven't been able to tell any MPG differences between the previous cab-high shell and my current shell which rises about 8" higher than the cab.

You say you're going 75-80. I understand that a lot of times when we travel we're just trying to get somewhere and obviously we don't like to spend time on the road but you'd be amazed at how much your MPG will jump when you drop the speed to 60 or so. Being a cheapskate I normally keep my speed no higher than 65 unless I'm in a real hurry to get somewhere. Not only is the MPG better but I find that the driving experience is much more pleasant because I'm not constantly jockeying for position, shifting lanes to pass or worrying about someone coming up behind me. On the interstates I just set the CC at 60 or 65 and stay in the right lane - I let everyone else go around me while I enjoy the view.

EDITED TO ADD: I'm running 235/85-16 Yokohama Geolander AT/S tires.

 

[Reece04]

Thanks for all the advice. I usually do Drive 65-70, at least in my Suburban because it is almost 2 to 3 mpg loss if I go any faster. Yesterday I was in a bit of a hurry. It is good to know that I am on par with pretty much everyone else. I think today is going to be the Deck Plate and the Gray wire mod, then next week it will go into the Mountains to play in the snow.

Again, Thanks for the peace of mind, and I hope you all have a Happy New Year!!!

 

[taco chaser]

I averaged 16 to 17 mpg highway at 65 to 70 mph and 15 to 16 mpg mountain roads running 4.88's pushing 37 x 12.5 x 15 goodyears. Stock was 18 to 20 mpg hwy.

 

[TacoTraveler]

I recently got some 285/75 BFG ATs and today was my first full tank of gas with them on. I averaged 16.6 mpg...
Do you think regearing from 4.10 to 4.56 would help bring it back up to the 18ish range?

 

[Martinjmpr]

I recently got some 285/75 BFG ATs and today was my first full tank of gas with them on. I averaged 16.6 mpg...
Do you think regearing from 4.10 to 4.56 would help bring it back up to the 18ish range?

Well, I'm not an expert in gear ratios but I don't quite see how that would be possible. Going to a lower gear means the engine is turning faster, not slower, so I don't see how that improves your MPG. Improves performance, yes, but MPG? I can't imagine how.

I haven't seen the torque curve for the 3.4l motor but my seat-of-the-pants impression is that the engine gets the best MPG if you can keep it around 2000 - 2200 RPM at cruising speed. I suppose if your tires are so big that you're at 1400 RPM at cruising speed a lower gear ratio might help.

You also have to consider that with those bigger tires you are now pushing more weight which will also reduce your MPG.

You didn't say how fast you were going but as noted above, MPG drops off drastically after about 65mph, so if you were cruising at 70 or 75, 16.6 is probably all you're going to get.

 

[dnellans]

I think you're right, looking at the principles there is some optimal gearing based on torque curve / fuel consumption of the engine. I'm not much of an expert in this area.

Based on practical experience having put larger tires on a few trucks with out re-gearing, and then later re-gearing some.... Going to larger tires almost always decreases your overall gas milage, its just more weight to get and keep rolling.

Without regearing I've often seen the same or slightly better milage on the highway because you're cruising at a lower RPM as you said, but driving around town the milage goes down because you tend to stomp the pedal to get the same pick-me-up as you previously had. After a re-gear back to "stock" ratios highway milage goes down but in town milage goes back up. Its still slightly lower than before stock because of the additional weight you've added however.

 

[Martinjmpr]

Without regearing I've often seen the same or slightly better milage on the highway because you're cruising at a lower RPM as you said, but driving around town the milage goes down because you tend to stomp the pedal to get the same pick-me-up as you previously had.

In that case it's not the gear ratio that's the problem, it's the pedal-stomping, which will almost always decrease your MPG.

 

[Cackalak Han]

Well, I'm not an expert in gear ratios but I don't quite see how that would be possible. Going to a lower gear means the engine is turning faster, not slower, so I don't see how that improves your MPG. Improves performance, yes, but MPG? I can't imagine how.

I am a noob at this, but just because the engine is turning faster doesn't mean it will necessarily be less efficient. There is a "sweet spot" for gear ratios that will be the best compromise between performance and efficiency. Stock ratio's hit this pretty well, but once the guy went to 33's, thus changing the gear ratio, it threw the efficiency of the engine off. Regearing (in this case, lower) makes the engine work more efficiently, thus giving the MPG a slight bump. Not sure if it'll get back up to 18, but you should see an improvement. Correct me if I am wrong in this.