Stupid Question About The Limited

As a SR5 Premium 4WD owner, I am wondering if the full time 4WD Limited model gets worse fuel economy then do all the other part time 4WD T4Rs?

It just seems to me running in 4WD full time would cause poorer fuel economy with the entire system engaged all the time?

And what about sharp turns when you have full time 4WD? Doesn’t that cause a wider turning radius? I notice on my SR5 that if I’m in 4WD, it sure doesn’t want to turn as sharply.

 

I believe it is rated at a slightly lower MPG.

Turning radius is the same because it is full time 4wd, not part time. Even part time has the same front end components at the Limited.

 

I’m not expert, did own a limited for a couple years. I believe there is a center dif which takes care of the turning issues.
And I don’t think the limited mpgs are lower, I think I remember the limited getting better from some.

 

I get about 16 17 in the city, about 19 to 21 or so on the highway with factory wheels and Toyo tires. As far as scuffing, our set up is different than the part time drive system. There are numerous articles and threads on the differences between the two.

 

Theoretically, yes, as there is more parasitic drag in the drivetrain would result in worse fuel economy. In practice, shit fuel economy 4Runner gets is not meaningfully impacted by having full time 4WD vs. 2WD mode.

No issues with sharp turns, this is why you have LSD.

 

I think Limited has lighter stock wheels and tires which makes fuel economy the same as part time 4x4. If you put wheels from SR5 then fuel economy would be probably a little worse. With part time 4x4 your front wheels locked in 4hi or 4lo modes, that's why you can bind front wheel if you sharp turn on dry pavement (which is strongly not recommended). Same thing will be true for Limited if you lock center differential, but in normal mode full time 4x4 doesn't affect turning.

 

The lower front facia may reduce drag and the narrow tires may reduce rolling resistance.

I think it would have been cool if Toyota offered the full time 4WD on other trims.

 

I just put on my winter rubber on 17s and took off stock 21s. Just from moving them around, 21s felt a lot heavier.

Are you sure?

 

I think its the opposite. Limited wheels are heavy.
I have a feeling the mpg is not much worse because of the relatively low clearance bumper and rocker panels. So not much wind drag.
When I weigh my (almost)Limited it was 60lbs more than my TRD Pro with every damn skid and sliders.

 

My favorite is 4Runner 4th gen v6 models multimode 4WD system. it has 2wd and when you shift to 4WD you have a center diff on & off selection. It would be perfect for my choice, so I could run on 2wd 99% of the time and use 4WD without center diff lock in inclement weather where I could do sharp turns at parking lots or u-turns with ease.

 

https://www.fueleconomy.gov/feg/bymodel/2024_Toyota_4Runner.shtml

Same, 2wd, 4wd, full time 4wd, etc. 16/19.

 

TRD Pro doesn't have 3rd row of seats and probably center differential is heavier than transfer case. Just a guess though. But bottom line is that stock Limited has the same fuel economy as other trims and we spend tons of money to modify our trucks and make fuel economy way worse : )

 

I have a 2wd limited i daily drive with 285s and i get about 18-19 if i drive it nice and about 16.5 if i drive "normal"
My wife HAD a 4wd limited with 20s and 305s and she drives like Bobby Labonte in a road course race and got 15.5
We got her a new TRD Sport 4wd (limited body, but SR5 style 4wd not full time) and has same tires and wheels, 20" with 305s and it gets 15.5

Basically there is no real difference in mileage between the AWD (full time 4wd) and the standard 4wd which is rear wheel drive until the selector is changed for 4wd

I will however say, the Limited AWD (full time 4wd) isnt actually pulling all 4 tires, i would venture to say its only pulling one rear wheel and one front wheel until the front diff locks. I have once before been climbing a hill and at the top of the hill had to drop over a ledge, and i hit it at an angle that caused the right front to drop over the ledge before the left front and i could physically feel the front end lock up and make it real actual 4wd with both front tires locked. I believe the front diff has some load sensor in the diff that locks the front end up when the axles get in too much of an angle or has more load on the gears or something. When you are in a limited, it feels like driving a standard 2wd, only when you get the front end in a bind or maybe if it senses wheel spin will it actually lock the front diff automatically.

 

I have a SR5 and a limited. They both are almost the same for MPG

 

For clarity’s sake:
FT 4WD is just that, full time. The center diff splits power 50-50 mostly but can vary the power a little bit, but not like an AWD system that will send all the power front until it senses tire slip. It’s the identical 4WD system you’ll find in the Land Cruisers and FJ Cruiser, minus the availability of a rear locker as you’d find in some LC and FJ trims.

The center diff in HF4 (unlocked center diff) allows the tires front and rear to turn at different rates so there is no binding. You can lock the center diff to have the 4WD system just like your SR5-P and the Limited would bind up just like the SR5 with the center diff locked as the front and rear axles are then turning (locked) together. The Limited also has low range, same as the SR5-P. The only setting it lacks is 2WD.

The front and rear differentials are open, not limited slip. The A Trac system applies the brakes to mimic a locker and in all but very severe off road situations, the A Trac system works fine.

I had a SR5-P before my Limited and I don’t notice any difference in MPG.

 

[QUOTE="Airdam, post: 652190, member: 40249"
I will however say, the Limited AWD (full time 4wd) isnt actually pulling all 4 tires, i would venture to say its only pulling one rear wheel and one front wheel until the front diff locks. I have once before been climbing a hill and at the top of the hill had to drop over a ledge, and i hit it at an angle that caused the right front to drop over the ledge before the left front and i could physically feel the front end lock up and make it real actual 4wd with both front tires locked. I believe the front diff has some load sensor in the diff that locks the front end up when the axles get in too much of an angle or has more load on the gears or something. When you are in a limited, it feels like driving a standard 2wd, only when you get the front end in a bind or maybe if it senses wheel spin will it actually lock the front diff automatically.[/QUOTE]

Nope. With FT 4WD in H4F (high 4, free center diff) all the wheels are driving if getting normal traction. Both the front and rear diff are open on a FT 4WD Limited - so if a front or rear wheel is freely spinning (off the ground, in an icy rut, etc...) then all the power will go to the spinning wheel - just like any other PT 4WD 4Runner that doesn't have lockable diffs. In this situation, go into L4L, turn on ATRAC and crawl out. However, with the center diff unlocked the transfer case is sending power to both the front and rear output shafts - and assuming both front/rear wheels are getting some traction the front and rear diffs are sending power to all 4 wheels. In H4F the center diff will alter how much power goes to front/rear. I think under normal traction situations it sends 60% to rear/40% to front - but can change between 30%front/70%rear to 70%front/30% rear depending on traction.

 

Thanks everyone for your replies!

 

I find it interesting that the new Land Cruiser has only full time 4 wheel drive. I wonder why that is.

 

The premium options in the lineup get full-time 4WD so someone spending that much and/or moving up from the Limited trim 4Runner won’t be off-put. It’s also standard on the GX I believe and serves as an upselling point too.

“You want more all-weather grip? Well just look at these options here for only $50/month more…”