The SR5 and Trail Edition part-time 4WD system is basically the same as the vast majority of part-time systems.
You are over-stressing about this. Your 4WD system will be just fine.
2010 4runner SR5, HELP PLEASE!!!
- Thread starter love_4runner
- Start date
You are over-stressing about this. Your 4WD system will be just fine.
1000MPH
Senior Member
I'm not saying it "is", I'm saying it's "considered" simpler and stronger. That being said, I would have preferred the FJ's full time 4wd manual, what can you do? Who knows why Toyota does what they do? Cafe standards? P/T is also "considered" to have better fuel economy...
I haven't seen anything that indicates part-time is any stronger.
1) Look at the 4th gen and compare the V6 with a multi-mode (can be run in 2WD) versus the V8 with full-time. There was 1-2 mpg difference in CAFE rating.
2) Look at the 5th gen and compare the rating between the SR5/TE (part-time) versus the Limited (fulltime). The are all rated the same: 17 city, 22 highway, 19 combined.
In other words, part-time doesn't have any better economy than multi-mode or fulltime. It is, however, significantly cheaper and the average buyer doesn't no the difference.
love_4runner
New member
I read the manual carefully again and here is what it says:
Four wheel drive system (part-time 4WD models)
H4 (high speed position, four wheel drive)
Greater traction than two wheel drive.
For when you experience a loss of power, such as wheel slipping.
It doesn't say anything about the road surface or binding problem. How can a customer know about this problem by reading the manual though?!
Four wheel drive system (part-time 4WD models)
H4 (high speed position, four wheel drive)
Greater traction than two wheel drive.
For when you experience a loss of power, such as wheel slipping.
It doesn't say anything about the road surface or binding problem. How can a customer know about this problem by reading the manual though?!
bradj
New member
If your tires were slipping on the dry pavement while parking then it was okay to be in 4wd due to loss of traction. If it was hard to turn and your weren't losing traction your shouldn't be in that mode
It isn't a "problem." It is how part-time systems work.
If that is all that the manual said, then, yes, the manual is insufficient.
love_4runner
New member
So far I have driven my new SR5 about 75 miles under 4WD includng the the highway @ 60 mph and a couple of parking lot slow sharp turns. Should I go to the dealer and checkup the damage?
No. There is no damage. Stop worrying.
love_4runner
New member
I hope so. Cuz I don't want the saleman who told me to drive part-time 4WD on any surface forever to loose his job! Life is not easy for everyone.
love_4runner
New member
Thanks a lot for the advices!
1) He wouldn't lose his job. Dealers don't care that their salesmen don't know their vehicles.
2) At most dealers, the annual turnover of salesman is above 100%. In other words, most salesmen don't last more than a year at a given dealership. Turnover is incredible.
The limited has narrower tires. Narrower tires = less contact patch = less drag = better fuel economy. There is more friction on a full time 4WD because the torque is transferring through 3 differentials instead of just one. Unless toyota created a no friction diff, there is power and efficiency lost. That is probably why the wheels on the Limited are a half inch narrower as well. That minimizes the amount of unsprung weight looking at it from a width perspective. The same goes for the narrower tires. Less unsprung weight.
Given two identical vehicles other than part time transfer case versus a full time 4WD, the part time will get better fuel economy. How much better, who knows? I doubt the 245 width tires on the limited were Toyota's engineers saying, "We need to somehow get some tires on the Limited to make it look less aggressive than the SR5/TE. Lets get some narrower wheels on there too, because that is all the rage these days."
Now, a torsion diff with multimode (2H, 4H, 4H lock, 4L lock) would definitely be the most ideal situation for capability and fuel economy, but cost goes up. I'm sure market research showed that most people wanted one or the other (budget minded wanted the cheapest version w/ 4WD still available, non-budget minded wanted full time 4WD), so that is why they made the decision they did.
Reducing unsprung weight is as much about ride comfort as it is about mileage. The Limited has those 20" wheels, with the resulting low-profile tires, which makes the ride significantly worse.
Apparently, not much. I doubt the economy difference between the different size tires is much, and since the TE, SR5, and Limited get the same mileage, the difference in mileage from the fulltime isn't much either.
Look at the minimal mileage differences between the 4th Gen V6 (multi-mode) and the 4th Gen V8 (fulltime). The V8 is a heavier, thirstier engine with fulltime 4WD, and yet its EPA rating wasn't all that much different than the multi-mode V6.
17 MPG (V8 4WD limited) and 20 MPG (V6 multimode 4WD limited) is pretty big, IMO. That is using almost 18% more fuel. You'd really have to have the only variable being the center diff (or lack there of) to make a true comparison. We need to get someone in a Limited 5th gen with SR5 wheels and do a rural and city loop to see what the actual delta is between full time and part time.
And how much of that is due to the V8? My guess is that the bulk of the difference is the V8, but that is just a guess.
