What do I have when the diffs aren't locked?

[5GENIDN]

also,



this might have some useful information, at work so haven't watched it, just remembered i saw it one time scrolling youtube.

Tires make a huge difference.... You can not get the power to the ground if the tires are not grabbing.... I bet I could make it over that with no lockers... no problem. But I have tires that will work much better in that scenario.

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[indio22]

Since we're on the subject... can anyone tell me how traction-control (in functionality) differs from limited-slip differential functionality? They seem to provide the same thing via different means. One with sensors and brakes (traction-control), and the other via the "limited slip" functionality of the differential.

They could indeed provide similar functionality. And for a majority of Bronco owners in particular on pavement, they would be a better choice than manual locker.

But apparently Ford failed to match Toyota and some other makes with implementation, in particular in 4low. Maybe Ford programmers were on vacation during that dev period.

 

[5GENIDN]

I thought pressing and holding the traction control button a few seconds disables AdvanceTrak. Maybe not 100%, but as close as one can get?

is AdvsnceTrac 100% disabled by default in 4lo? Seems yes.

Yes... you do not want the brakes applied on an axle if it is locked... Absolutely no benefit... in fact would be a detriment. Also there would not be ANY speed differentiation between the two tires on the same axle.

 

[5GENIDN]

They could indeed provide similar functionality. And for a majority of Bronco owners in particular on pavement, they would be a better choice than manual locker.

But apparently Ford failed to match Toyota and some other makes with implementation, in particular in 4low. Maybe Ford programmers were on vacation during that dev period.

Maybe I am not understanding you comment....

Ford has traction control.

When the hell am I ever going to use 4L on the pavement? never... I like that it turns off automatically when I go to 4L.... I do not want it on when I have lockers on and well I turn my lockers on and off (depending on obstacle) constantly.... Most of the time I do not need them but when I do I just hit the button and when I am over the obstacle I hit the button again...

You absolutely do not want that on when a locker is engaged.

 

[indio22]

Maybe I am not understanding you comment....

Ford has traction control.

When the hell am I ever going to use 4L on the pavement? never... I like that it turns off automatically when I go to 4L.... I do not want it on when I have lockers on and well I turn my lockers on and off (depending on obstacle) constantly.... Most of the time I do not need them but when I do I just hit the button and when I am over the obstacle I hit the button again...

You absolutely do not want that on when a locker is engaged.

Not everyone has lockers. And for most Bronco owners on/off pavement, a well implemented brake actuated limited slip diff would be a better option than manual lockers.

 

[CalvinT]

can anyone tell me how traction-control (in functionality) differs from limited-slip differential functionality?

Back in the day you could simulate traction control with a car that had a hand operated emergency (parking) brake. If you noticed one of your rear wheels slipping, you could pull up on the emergency brake slightly to load the slipping wheel (it would also load the other wheel). That would force a torque transfer to the wheel that had traction. Not possible with an electric parking brake.

 

[UncleBrad]

No explanation needed, you are 100% correct. A well-tuned TC system can perform exceptionally well in challenging conditions.

If you crawl underneath a Bronco Sport, you will not find a proper Dana (mechanical) rear differential. You'll find a fragile-looking, heat-sinked "rear diff" contraption which contains clutches, which in turn connect to the axles. There also is a clutch assembly responsible for transferring power to the front (roughly analogous to the mechanical transfer case found in the Bronco). This is the fundamental design found in modern AWD vehicles today. They are absolutely dependent upon software control, clutches and sensors.

In the Badlands version of the Bronco Sport (which can simulate a "rear diff lock") this "rear diff" contraption is water-cooled. Why? Because under "challenging conditions" these designs succumb to heat. All those clutches get hot, and the system will go into a limp mode (or stop altogether) until things cool down. Rather like an old PowerGlide on a hot summer day.

YouTube is full of videos of Subaru's in "X-Mode" loosing power and stopping at the worst possible time (often while trying to build momentum). Subie owners learn to periodically ease off the trail and wait for a cool-down, while the Wranglers and Broncos pass them by.

These AWD systems can and do grow weak or fail for the same reason as a 1997 Nissan Quest's brakes get hot when repeatedly going down steep Rocky Mountain roads - eventually putting you in a perilous pucker position (ask me how I know).

Once I crawled underneath my Bronco Sport and saw how complex, fragile and vulnerable this AWD system really was, I traded in the Bronco Sport for a Bronco (with a proper mechanical rear differential and transfer case).

I very much doubt that these AWD systems can perform "exceptionally well in challenging conditions" - but I will agree that they can very work well for tougher on-road challenges, like snow or icy surfaces. Or hitting some trails.

The Bronco Sport does have a superior AWD system over its competitors, but there is a reason why there aren't near as many at the Bronco Off-Rodeos: they can't handle what the Broncos can. It's a very different, compromising design philosophy.

 

[UncleBrad]

Not everyone has lockers. And for most Bronco owners on/off pavement, a well implemented brake actuated limited slip diff would be a better option than manual lockers.

Yes! In snow, especially on a cambered surface, locking diffs (and even limited slip if you're not careful) can get you in trouble. I may do limited slip on my Big Bend...

 

[DALOLA]

If you crawl underneath a Bronco Sport, you will not find a proper Dana (mechanical) rear differential. You'll find a fragile-looking, heat-sinked "rear diff" contraption which contains clutches, which in turn connect to the axles. There also is a clutch assembly responsible for transferring power to the front (roughly analogous to the mechanical transfer case found in the Bronco). This is the fundamental design found in modern AWD vehicles today. They are absolutely dependent upon software control, clutches and sensors.

In the Badlands version of the Bronco Sport (which can simulate a "rear diff lock") this "rear diff" contraption is water-cooled. Why? Because under "challenging conditions" these designs succumb to heat. All those clutches get hot, and the system will go into a limp mode (or stop altogether) until things cool down. Rather like an old PowerGlide on a hot summer day.

YouTube is full of videos of Subaru's in "X-Mode" loosing power and stopping at the worst possible time (often while trying to build momentum). Subie owners learn to periodically ease off the trail and wait for a cool-down, while the Wranglers and Broncos pass them by.

These AWD systems can and do grow weak or fail for the same reason as a 1997 Nissan Quest's brakes get hot when repeatedly going down steep Rocky Mountain roads - eventually putting you in a perilous pucker position (ask me how I know).

Once I crawled underneath my Bronco Sport and saw how complex, fragile and vulnerable this AWD system really was, I traded in the Bronco Sport for a Bronco (with a proper mechanical rear differential and transfer case).

I very much doubt that these AWD systems can perform "exceptionally well in challenging conditions" - but I will agree that they can very work well for tougher on-road challenges, like snow or icy surfaces. Or hitting some trails.

The Bronco Sport does have a superior AWD system over its competitors, but there is a reason why there aren't near as many at the Bronco Off-Rodeos: they can't handle what the Broncos can. It's a very different, compromising design philosophy.

Of course, you are 100% correct.

I should have been more specific, my comment about challenging conditions was referring to on-road. I just assumed most people understand the AWD/TC style short comings when off-road. The reference was to draw the parallel to LS vs TC, as the person I quoted was questioning.

Thanks for the excellent post to clarify.

 

[bassist]

Since we're on the subject... can anyone tell me how traction-control (in functionality) differs from limited-slip differential functionality? They seem to provide the same thing via different means. One with sensors and brakes (traction-control), and the other via the "limited slip" functionality of the differential.

Yes.

Even though we might romanticize limited slip, it's inferior to traction control because it doesn't work out what it SHOULD do, it can only do what it is designed to do.

I had a chain reaction of failures once on a Jeep that would have been far less of an issue if it didn't have a limited slip in place. Instead of spinning a tire, things broke.

 

[bassist]

Yes! In snow, especially on a cambered surface, locking diffs (and even limited slip if you're not careful) can get you in trouble. I may do limited slip on my Big Bend...

I wouldn't even bother with limited slip. Computer controlled is typically a lot better -- and sometimes better than actual lockers.

Even though I had a rear locker in my 4Runner, there were times when the A-TRAC was exactly the best solution to the problem.

 

[bassist]

Maybe I am not understanding you comment....

Ford has traction control.

When the hell am I ever going to use 4L on the pavement? never... I like that it turns off automatically when I go to 4L.... I do not want it on when I have lockers on and well I turn my lockers on and off (depending on obstacle) constantly.... Most of the time I do not need them but when I do I just hit the button and when I am over the obstacle I hit the button again...

You absolutely do not want that on when a locker is engaged.

There are some times when traction control can be useful when in 4L...

Specifically when you're on a trail with snow and ice that has been through a few freeze/thaw cycles. I've seen video of someone at low speeds going over the edge where traction control might have kept the situation from escalating.

It is interesting that the blokes down under throw their lockers on first, while in the US people tend to try the obstacles without lockers the first time.

 

[UncleBrad]

I wouldn't even bother with limited slip. Computer controlled is typically a lot better -- and sometimes better than actual lockers.

Even though I had a rear locker in my 4Runner, there were times when the A-TRAC was exactly the best solution to the problem.

But if a person does not have a "computer controlled" solution (like me) to begin with, yours is a moot point.

 

[Sparkherd]

You have the ability to tackle the most extreme curbs at any mall. As long as you have some momentum.

Hyuk!!!
I remember, in Them Good Old Days, when all anybody had was open diffs!
Now we have a choice of open, brake-based traction control (Ford's version SUCKS compared to Toyota's, BTW), or a locked diff, AND PEOPLE ARE STILL BITCHIN!!!

 

[crzyhawk]

They could indeed provide similar functionality. And for a majority of Bronco owners in particular on pavement, they would be a better choice than manual locker.

But apparently Ford failed to match Toyota and some other makes with implementation, in particular in 4low. Maybe Ford programmers were on vacation during that dev period.

Perhaps I am jaded, but I feel like better traction control would incentivize fewer people to purchase locker options that they otherwise would not need/want. I'm not sure I am ready to just throw the incompetence flag when the greed flag might be more appropriate.

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