V6 vs. V8 gas mileage

[4Beast]

Whatever figures people are quoting for their fuel economy aren't important. What are important are the inherent characteristics of both the V6 and V8 engines. The V8 produces around 13% more horsepower (max), 15% more torque (max), has two additional cylinders and weighs ~200 lbs more than the V6 engine (I'm using 2006 SE edition). There is no way - repeat, NO WAY - that the V8 engine will match or even slightly trail the V6 in terms of fuel economy. Think about it - if it was so easy to improve performance while barely affecting the fuel economy, why would engineers even bother with a V6? If the V6 gets 19 MPG and the V8 gets 18 MPG, who in the world would even consider a V6?

Forget what the EPA ratings say - they're crap, and we've known that for years. The V8 is going to use significantly more fuel because it is designed to; We're feeding more pistons to produce more HP and Torque. I think this discussion is akin to discussing the recoil between a .38-cal and a .40-cal; the .40-cal bullet is heavier and produces greater muzzle energy. Therefore, the recoil will be worse. No matter how we try to sugar-coat things, the physics behind the reaction cannot be negotiated.

My previous ride was an E39 M5, which had a marvelous V8 394HP/368FT-LBS engine that leapt like a lion when I stabbed on the throttle. Which brings me to another point - V8 driving habits. Nobody who has a V8 tiptoes around town - we USE that torque because it puts a smile on our face. I would call it a "common sense" theory that if we took 10 guys and let them drive V6 4runners half the day, and then V8 4runners the other half of the day, the data would tell us that people absolutely had heavier feet in the V8.

Don't get me wrong, the V8 is the preferable engine for folks who 1) want a muscle-car feel in an SUV and/or 2) tow regularly. That's fine, but don't be fooled into thinking that the fuel consumption between the two models will be negligible. The V8 has about 15% better HP and Torque, and I'd be willing to bet that on average it gets about 15% worse fuel economy, too. Add on the "performance" penalty for lead feet, and I'd set a safe estimate that the V8 gets about 20% lower fuel economy than the V6.

I think that you are probably correct regarding the penalty for having a V8 being something like 15% or so, but in some ways that is close enough to prolong the debate, not solve it. For example, for those 6ers who get 22mpg (a decent average) the 15% penalty is 3.3, so the 8s are at 18.7 (which many report) so they are still somewhat close for some people.

These debates seem to go on forever between the V6 and 8 and the truth is that some people are fine with a 15% percent hit and for others it is unacceptable. I don't think it helps that a few V6 owners often grossly exaggerate their mileage (ahem, 27, ahem) possibly because they are trying to amplify the only real advantage that the V6 has.

For what it's worth, with the winter blend, and 255/75/17s I get about 16 mpg in mixed/stop-and-go driving.

 

[8086bruce]

07 4WD V6 I get 16 city and 19 hwy if I drive nice.

 

[Presta24]

07 4WD V6 I get 16 city and 19 hwy if I drive nice.

Wow..really? glad I got the V8

 

[get2thechoppah]

I think that you are probably correct regarding the penalty for having a V8 being something like 15% or so, but in some ways that is close enough to prolong the debate, not solve it. For example, for those 6ers who get 22mpg (a decent average) the 15% penalty is 3.3, so the 8s are at 18.7 (which many report) so they are still somewhat close for some people.

These debates seem to go on forever between the V6 and 8 and the truth is that some people are fine with a 15% percent hit and for others it is unacceptable. I don't think it helps that a few V6 owners often grossly exaggerate their mileage (ahem, 27, ahem) possibly because they are trying to amplify the only real advantage that the V6 has.

For what it's worth, with the winter blend, and 255/75/17s I get about 16 mpg in mixed/stop-and-go driving.

Well put. If a person can accept up-front that driving a V8 will likely cost 15%-20% more in fuel/year, that is completely a personal choice. I did a quick calc and agree with the ~3 MPG hit that you estimated. If we say (for experiment's sake) that the V6 averages 20 MPG and the V8 averages 17 MPG, and both cars drive 15,000 miles/year, the V6 annual fuel cost will be $3000 and the V8 annual fuel cost will be $3530 (both at $4/gal). The difference is $530/yr or $44/mo.

To some people, that's a significant difference. To others it is barely noticeable

 

[ThreeFiveO]

From my experience, it's safe to say the v6 gets better mileage in a stock configuration. The v8 is feeding gas to two extra cylinders whether your utilizing the power or not (sitting in traffic, highway cruizing, etc..)

When you start adding weight and drag with items such as lift, wheels, tires, and bumpers, the v8 is going to handle the additional load better than the 6, it just has the extra low end torque on tap to handle the load. As a result the v6 loses it's MPG advantage at an increasing rate as you load it down with "stuff" like we all do.

My 3rd gen v6 towed fine, but it got worse MPG than my 4th gen v8 towing the same trailer, similar concept as adding weight and drag from wheels, tires, lift.

Now my old 94 3vze (3.slow) truck on 35-14.5 swampers is not only the smallest engine of the bunch, but it's also the slowest and eats more gas than both without anything behind it.

Just my .02 :cowboy:

 

[4RNNR]

sorry, but I'm pretty sure, higher octane gas will NOT give you any more HP

I'm getting almost 20MPG with my '08 / V6

 

[webby]

Can you please provide a link to where we can read about and buy said magic magnets?

Also I put 2 15,000 Gausee Neodynium magnets on my oil filter which somehow (less microscopic internal friction>>>>>>? no clue? it just works) really improved my mileage by 1.5 MPG (can pay off those magnets after 4 tanks of gas.

 

[truckmike26]

I'll always maintain the V8 doesn't net a propotional acceleration increase. Fifteen to 20 percent more fuel doesn't get you 15 to 20 percent better acceleration and no better braking or road-holding ability.

My '10 5.7L short-wheelbase Tundra gets SLIGHTLY BETTER mileage than my mostly stock, '94 3VZE NoForce V6 -- around 16 mpg -- and the Tundra's 1000 lbs. heavier.

 

[truckmike26]

sorry, but I'm pretty sure, higher octane gas will NOT give you any more HP

I'm getting almost 20MPG with my '08 / V6

Splurge and fill with premium for a month and see what happens.

 

[JB.]

sorry, but I'm pretty sure, higher octane gas will NOT give you any more HP

I'm getting almost 20MPG with my '08 / V6

This one's an endless debate loop.

Toyota, however, suggests it does:


Select Octane Rating of 87or higher. For
improved vehicle performance, the use
of premium unleaded gasoline with an
Octane Rating of 91 or higher is recommended.

 

[lbrunner]

Sequoia

After reading this thread and some of the logic, I have this question:

Why does a 08+ sequoia 5.7 with I think 1000 pounds and 110+ hp more than an 05+ 4runner, get 16-18mpg. I have had an 05 v8 and currently have 08 Limited V8 and 05 V6 sport. Both V8's never got over 19 and almost always got 17-18, winter is a dismal 15.5-16 if I'm lucky. I love my V8 but I still think the V8 is a pig. 260 or 270hp is not a big number today. While I still love the reliability of the 4runner, I just don't get the numbers when comparing a sequoia to the 4runner. Is one extra cog in trans the reason? I wonder what a 4.6 with a 6 speed would get in the 10 4runner.

 

[Chris Sandstorm]

Interesting read for sure.

I am getting 20-21 on the highway with my 255/85/16s. This blows the doors off my FJC. I wrestled with the v8 vs. V6, until I did some pros and cons for my needs.

Better gas mileage, no heavy towing, long distance off-road travel through southern Utah, 2wd on highway, no timing belt maintenance at 100k, less ware on the front diffs..

 

[klennop]

I'll always maintain the V8 doesn't net a propotional acceleration increase. Fifteen to 20 percent more fuel doesn't get you 15 to 20 percent better acceleration and no better braking or road-holding ability.

You don't think when towing something at 5000lbs or even having the max load in your vehicle you would notice a 15-20% better job with the V8? I would have to disagree.

And as far as road holding, I will take my constant 4 wheel drive system in crappy weather, rain, snow, ice, etc. over having to engage it when needed. Life and death comes pretty fast when **** hits the fan. So to some that added feature alone makes up for the 15-20% hit in fuel.

 

[Presta24]

i always got 17-20 in my v8, until the MT's, now i get 14-17

 

[truckmike26]

You don't think when towing something at 5000lbs or even having the max load in your vehicle you would notice a 15-20% better job with the V8? I would have to disagree.

And as far as road holding, I will take my constant 4 wheel drive system in crappy weather, rain, snow, ice, etc. over having to engage it when needed. Life and death comes pretty fast when **** hits the fan. So to some that added feature alone makes up for the 15-20% hit in fuel.

No, I don't think when towing something at 5,000 lbs. or even having the max load in your vehicle I would notice a 15-20 percent better job with the V8.

V6 4WD 4Runners have the option of 2WD for those who like to live on the edge.

 

[klennop]

No, I don't think when towing something at 5,000 lbs. or even having the max load in your vehicle I would notice a 15-20 percent better job with the V8.

V6 4WD 4Runners have the option of 2WD for those who like to live on the edge.

OK I strongly disagree but maybe you don't tow anything heavy enough to notice. I guess Toyota put the V8 in the 4runner for no reason.

This is my first 4WD truck/suv where it is in 4WD all the time. I thought I would really miss having 2WD because I always liked screwing off in 2wd but I don't miss it. I can still walk it sideways when it is wet or in crummy weather. Plus it is really nice not to have to put it in 4WD if I need it at the drop of the hat, one less thing to deal with.

 

[6starbucks]

sorry, but I'm pretty sure, higher octane gas will NOT give you any more HP

I'm getting almost 20MPG with my '08 / V6

yes the higher octane does give you a little bit of boost in hp/torque its only about 5hp/torque difference between 85 and 91

 

[Joe D]

V-8 2004 Sport Edition

I have an 04 V-8 SPORT and Im very happy with my choice over the V-6 but it really is a personal choice. I do a tow a pop up camper around during the summer and you forget its there with the V-8. Best truck I ever owned,,,,very quiet tight ride. In an earlier post somebody mentioned replacing plugs on the v-6 at 30k...How about the V-8 AWD...Just hit 50 k today. Same plugs, same battery, same great ride.

 

[truckmike26]

OK I strongly disagree but maybe you don't tow anything heavy enough to notice. I guess Toyota put the V8 in the 4runner for no reason.

This is my first 4WD truck/suv where it is in 4WD all the time. I thought I would really miss having 2WD because I always liked screwing off in 2wd but I don't miss it. I can still walk it sideways when it is wet or in crummy weather. Plus it is really nice not to have to put it in 4WD if I need it at the drop of the hat, one less thing to deal with.

You're probably right. A V8 4Runner does tow a 5,000-lb. load slightly better than a V6 4Runner -- and there are tens of thousands of V6 and V8 4Runner owners who frequently tow 5,000 lbs. who'll agree.

 

[Ducman]

Each

I never understand why these type of threads always turn into a 'one is better than the other' type of discussion. To each his own.

The reason I bought a V8 is I just love the low end torque, I love the sound a V8 makes and I love the no hassle full-time 4WD (especially for when my wife has the truck with our kids)

To me the timing belt is no big deal and I will change it myself when the time comes.

If an extra MPG gives you warm fuzzies, timing belt maintenance scares you, or you dont want full time 4WD then rock the V6 and wear a smile.

We are all 4runner owners here, choices are good. :cheers: