2014 Limited four-wheel drive questions

[SouthernSS]

I am talking about the part underlined above, that a center locked AWD and a part time 4WD work the same - both drive shafts turn at the same speed. I agree with everything in JB's post, actually.

Gotcha

 

[nevada]

Actually, it's pretty much the same. Both drive shafts turn at the same rate. I can't imagine the center diff is so fragile it blows up by making a left hand turn on pavement.

I drive on slickrock all the time (higher grip than most pavement) in 4wd (both drive shafts turning at the same rate). Tires chirp and squeal, but haven't broken anything in the driveline, yet.

it is very unwise to lock the CDL when on pavement, unless its a completely straight section of road. I have seen more than a few busted rigs because of this. be it cv axles, tcases, or front differentials.

offroad its ok, you are going much slower, and there are times where a tire gets to slip a bit, relieving the pressure that is built up. you wont get that on pavement.

but even offroad, lock it up, get on some of that slickrock, turn the wheel to full lock and stab the throttle like you are pulling out into traffic. theres a very good chance something will break.

 

[Jeremy556]

but even offroad, lock it up, get on some of that slickrock, turn the wheel to full lock and stab the throttle like you are pulling out into traffic. theres a very good chance something will break.

At 12psi, 4.56 gears, and low range, I'm not gonna try that one out. :yield:

I don't think the driveline is as fragile as many people believe, is what I'm getting at. I have a friend, who is the absolute worst driver I have ever seen, uses only full throttle or ABS braking. He forgot to take his 250K mile Yukon out of 4hi before he left Colorado, drove back to Florida, and didn't notice it was still in 4wd for several weeks, or a month later.

 

[Bilbo]

THANK YOU PROQUIP!
You are the first person to actually read the question and answer it. And you are correct, I mis-quoted that first setting.

Now, does anyone actually know what percent power goes to the front wheels and what percent power goes to the rear wheels in the H4F setting?

Thanks to all for your help.
spm

Ahem. I think you'll find my answer above. But just to repeat:

"According to the 2014 4Runner Product Information Sheet, the normal unlocked center diff split is 40% front and 60% rear. As needed, this can range from 30-70 to 53-47."

You can find the sheet here:
2014 Toyota 4Runner Product Information | Toyota

 

[spm]

Ahem. I think you'll find my answer above. But just to repeat:

"According to the 2014 4Runner Product Information Sheet, the normal unlocked center diff split is 40% front and 60% rear. As needed, this can range from 30-70 to 53-47."

You can find the sheet here:
2014 Toyota 4Runner Product Information | Toyota

You are correct, Bilbo. I apologize for slighting you. I guess I too am guilty of not reading the complete post before responding.

thank you,
spm

 

[Bilbo]

You are correct, Bilbo. I apologize for slighting you. I guess I too am guilty of not reading the complete post before responding.

thank you,
spm

No worries! It gives us a chance to raise our post counts.

 

[JayceeP]

[MENTION=113159]spm[/MENTION] I don't think the first option is H4H, but rather H4F

H4F is high (H) range 4WD, unlocked center diff, full-time (F) 4WD. You should be in H4F for everyday driving.

H4L is high (H) range 4WD, locked (L) center diff. It behaves similar to a part time 4WD. Power is distributed to both front and rear axles 50/50. Use H4L on slippery surfaces to prevent binding of the drivetrain.

I honestly don't know what I am talking about, but wouldn't driving in H4L in dry conditions risk binding the drivetrain?

This is important for me. I haven't taken the 4Runner out of H4H since buying it last March lol. Never had a need to use H4L let alone L4L, but will use H4L on really snowy days now that I understand better.

 

[1engineer]

The center diff lock is, imo, a great feature. It guarantees that at least 1 front wheel and 1 rear wheel will spin at the same rate. Couple this with Atrac and you've got an incredibly capable stock vehicle. Dont EVER use it on pavement though, or you WILL break something in the driveline.

The GX470 is also an all time 4wd truck with the center diff lock and there hasnt been a single obstacle I've pointed that truck at it couldnt crawl over with the help from some electronic wizardry. This includes some Level 5 trails I had no business being on , lol.

Sorry my friend but your information is inaccurate despite what you witnessed in one instance. [MENTION=78273]Jeremy556[/MENTION] explained it well. Do you actually think Toyota would release a design that would do 3K in damage after mistakenly pushing a button or turning a knob and then making a left turn? Me either.

 

[JB.]

Well I've seen it happen during a test drive that ended early because my friend who was unaware of what that button did, pressed it while at a stop light to turn left. As he went to take off we heard some popping/clicking tire chirping that got louder as the turn radius got tighter until POW and a jolt. Im not eactly certain what teeth were sheared where, but it wasnt drivable anymore and had to be towed back to the dealership.

Luckily they didnt fault him for it, but I certainly wont be trying it on my truck on dry pavement.

What vehicle are we talking about?

 

[03_4x4Runner]

I honestly don't know what I am talking about, but wouldn't driving in H4L in dry conditions risk binding the drivetrain?

This is important for me. I haven't taken the 4Runner out of H4H since buying it last March lol. Never had a need to use H4L let alone L4L, but will use H4L on really snowy days now that I understand better.

You better go to H4L and L4L every couple months or the actuator will get stuck and not work at all. Use it or loose it.

 

[JayceeP]

You better go to H4L and L4L every couple months or the actuator will get stuck and not work at all. Use it or loose it.

Yeah, I realize there are potential implications. I don't live near long dirt roads so unfortunately it just isn't a priority. Is there anything that would be a giveaway of a problem when switching?

I didn't remember seeing anything in the manual that discusses this kind of maintenance, but I also didn't read every single page either.

 

[Bilbo]

You better go to H4L and L4L every couple months or the actuator will get stuck and not work at all. Use it or loose it.

Yes. There must be one or two gravel roads in NS you can drive. Better to see that your system works, and to keep it working, rather than wait for winter to arrive.

As to when you should be in H4 Free vs. H4 Locked, I think most would agree about when you shouldn't use it. Don't make a practice of locking the differential on dry pavement. It seems to me, however, that when you should use it is a matter of some personal preference.

If you have a part-time 4WD, then it's clear there is a huge difference between free vs. engaged. It's a matter of 0/100 vs. 50/50 torque split.

But for a full-time 4WD, the benefits of locking the center diff in H4 are only incremental: 40/60 vs. 50/50 split.

L4 Locked is another matter ...

 

[JayceeP]

Yes. There must be one or two gravel roads in NS you can drive. Better to see that your system works, and to keep it working, rather than wait for winter to arrive....

......If you have a part-time 4WD, then it's clear there is a huge difference between free vs. engaged. It's a matter of 0/100 vs. 50/50 torque split.

But for a full-time 4WD, the benefits of locking the center diff in H4 are only incremental: 40/60 vs. 50/50 split.

L4 Locked is another matter ...

Haha, I know. Just nothing too close. The only obstacles nearby are the speed humps I flex over in the McDonald's drive thru/parking lot.

Thanks for the other parts. That's more or less what I suspected and that seems to make a lot of sense!

 

[Jeremy556]

Haha, I know. Just nothing too close. The only obstacles nearby are the speed humps I flex over in the McDonald's drive thru/parking lot.

Thanks for the other parts. That's more or less what I suspected and that seems to make a lot of sense!

You won't hurt anything as long as you go straight. I would recommend exercising the actuators regularly. You don't really need to do any distance, just lock and unlock cdl, and shift into 4lo.