AWD godmode fail

[wirednuts]

No, both wheels in a 2WD system with an open differential get power, not just one. Just the max that can be applied is equal to the least amount required to spin one wheel. So if one wheel spins (on ice for example), the other wheel only gets the same amount, which isn't enough to move the vehicle so it doesn't go anywhere. Same idea with 4WD on a per-axle basis if both front and rear have open differentials.

which is exactly what i mean....

 

[SparkyJJO]

which is exactly what i mean....

So you meant one thing and said another?

 

[michal1980]

which is exactly what i mean....

no you said 1wd.

Which with open diff's is just wrong. in a 2wd drive car, as traction to one wheel goes to zero, so does the other, in effect making it 0wd drive.

The same thing happens with 4wd systems that have open diff's. IE if traction on 2 wheels on different axles goes to zero, your 4wd system is now a 0wd system. You will have 2 wheels spinning, and 2 wheels just sitting there.

Some traction control systems cheat, and use brakes to hold/slow down the spinning wheel so that traction goes to the other wheel to help you move.

 

[LTC8K6]

most cars are like this. any 2wd car is really 1wd, and any 4wd is really 2wd corner to corner. positraction can help, if its working well... but it also gives you less traction on cornering...

No. Many 2wd vehicles are 2wd vehicles and many 4wd vehicles are 4wd vehicles.

 

[SparkyJJO]

no you said 1wd.

Which with open diff's is just wrong. in a 2wd drive car, as traction to one wheel goes to zero, so does the other, in effect making it 0wd drive.

The same thing happens with 4wd systems that have open diff's. IE if traction on 2 wheels on different axles goes to zero, your 4wd system is now a 0wd system. You will have 2 wheels spinning, and 2 wheels just sitting there.

Some traction control systems cheat, and use brakes to hold/slow down the spinning wheel so that traction goes to the other wheel to help you move.

Slight correction - traction doesn't go to zero on the other two wheels, just power is next to nothing so it won't move the vehicle

I've manually done the cheat with the brakes before. You just have to be careful doing that as doing it manually is an easy way to burn the brakes if you aren't careful

 

[Greenman]

Why is your front yard a mud hole?

 

[michal1980]

Slight correction - traction doesn't go to zero on the other two wheels, just power is next to nothing so it won't move the vehicle

I've manually done the cheat with the brakes before. You just have to be careful doing that as doing it manually is an easy way to burn the brakes if you aren't careful

technically right. But the amount of power going to the other wheel can be rounded down to zero. As its equal to the force required to spin the free wheel.

I've heard that the traction control systems that use brakes as a fake diff, can burn through brakes much faster, if your really on it.

I had a VW rabbit, that used brakes for the front diff, actually had a sensor/timer that disabled the system if you used it too much so the brakes wouldn't overheat.

Happened to me once when I parked on 4 inches of packed snow overnight. Then tired to get out in the morning, rocked back and forth for a bit, but then the brakes stopped doing their e-diff thing.

 

[ballmode]

doesn't sound like these automatic subaru systems are even remotely close to a 4wd system in a truck/suv/jeep

 

[wirednuts]

one wheel always spins faster, the other might not be pulling very hard but at least its gripping... im not arguing with you guys. im just saying it weird

 

[skyking]

Why is your front yard a mud hole?

He's in Arizona, it rained

 

[jlee]

fixed that for you.

lmao. Touche.

He's in Arizona, it rained

Aaand this too.

doesn't sound like these automatic subaru systems are even remotely close to a 4wd system in a truck/suv/jeep

My Forester had a 50/50 split front/rear, open diff front and LSD rear, which is actually better than some 4wd systems with open front/rear diffs. Regardless, put all season passenger car tires on a 4wd truck and stomp on the throttle when you're sitting in squishy mud and see what happens.

 

[skyking]

I bet he runs his ass outside next time there is a downpour like that.

 

[michal1980]

lmao. Touche.



Aaand this too.



My Forester had a 50/50 split front/rear, open diff front and LSD rear, which is actually better than some 4wd systems with open front/rear diffs. Regardless, put all season passenger car tires on a 4wd truck and stomp on the throttle when you're sitting in squishy mud and see what happens.

Your rear LSD is what makes it a far better 4wd system then alot of them on the market.

From my reading on subies its also one of the bigger pluses of the forester vs say the base impreza.

Now if you had an STI you'd really be rollin, not only does it have a trick locking center diff, but it has front and rear LSD.

 

[manimal]

Now if you had an STI you'd really be rollin,

wouldnt we all!

 

[LTC8K6]

https://www.youtube.com/watch?v=mryGnENTsoI

 

[LTC8K6]

Up until 2011, Quadra Drive 2 had ELSD's front and rear. Now it only has it on the rear.