[davidbanham]

Locking differentials are very useful in particularly challenging terrain. Think step rough rock climbs or soft sand. For punting along an average fire trail or dirt road, though, it’s clearance, strong tyres and suspension travel that’s more important.

A Subaru has none of the above. They make great cars, but they’re not an off road vehicle.

[quasse]

I say this as a Jeep owner; it's ridiculous to claim that Subarus are not appropriate for punting along fire trails. The average obstacle on fire trails in the PNW is mud or large potholes, both of which a Subaru is perfectly appropriate for. A Crosstrek has 8.7in of ground clearance which is plenty compared to say, a Prius.

That being said, the trail from the linked article is not an average fire road. They have genuine rock hazards, steep slick rock climbs and descents, and deep sand. I'm sure the national park service is extremely tired of people getting stuck and setting off their emergency beacons because they drove inappropriate vehicles into the park.

[barkingcat]

the previous poster didn't say that subarus are not appropriate for fire trails, it's saying that Subaru's are not off road vehicles for "particularly challenging terrain", as in "Think step rough rock climbs or soft sand."

What it does say is that for fire trails, "clearance, strong tyres and suspension travel" are more important, which the Subaru does quality for.

[quasse]

> it's clearance, strong tyres and suspension travel that’s more important.

> A Subaru has none of the above.

Maybe you and I take different meanings from the phrase "none of the above". My intended meaning was that a Subaru has "some of the above".

[davidbanham]

You correctly interpreted my meaning with "none of the above". An older gen Forester with a good set of tyres fitted can fit the bill, for sure. The Subaru Brumby is an outback legend and you still see plenty of them rolling around, going more places than you'd imagine possible.

A Subaru Crosstrek wearing it's original HT tyres, though? It's not intended as an off-road vehicle. That's not what it was built for. Low clearance, insufficient travel, weak tyres.

[worthless-trash]

Can confirm the Brumby behavior, If there is one vehicle you will see driving like a maniac on the the CREB / Bloomfield track in North Queensland it's a brumby driver usually with a ZZ Top length beard.

[SR2Z]

But "clearance, strong tyres and suspension travel" have NOTHING to do with 4WD vs AWD, which as far as I can tell is kind of a silly distinction since nowadays cars have sophisticated enough drivetrains that they can use brake-based torque vectoring to force up to half the engine torque into one wheel.

[avar]

They clearly could do that, since ABS systems allow for independent braking on each wheel.

But I'm unaware of any production AWD vehicle which allows that as a "hack" to emulate a sort-of locked differential when your hardware is an open differential.

It's probably used as part of computer controlled traction control on some vehicles, but those systems are usually too smart for their own good in off-road and similarly challenging conditions.

[davidbanham]

Actually independent wheel braking as part of an electronic traction control system is pretty common and _can be_ excellent. The Land Rover Discovery looks to have gotten a bit soft in the latest iteration, but they've used that system for years. Coupled with the coil suspension all round with good articulation, they're well regarded off road. Not long-term durable on high speed rough roads, mind you, but brilliant at climbing a snotty hill.

For serious or regular off road work, a mechanical locking diff is the way to go. Yes, most electronic systems will completely freak out and stop you going anywhere in soft sand until you remember to turn them off. They do have their place though.

[SkyPuncher]

Many production AWD systems include this. My Hyundai Palisade has it (in addition to an actual locking rear differential).

That being said, it’s amazing for snow and ice, but I would not trust it to get me unstuck from rocks or a ditch.

[kevinpet]

I'm pretty sure all recent Subaru's (other than BRZ, which is a totally different platform) have wheel spin control using the braking system.

[aeonik]

They do, though some use a clutch-based system. They have 4 different systems if I am not mistaken.

https://www.youtube.com/watch?v=WBQlK89PyxQ

[davidbanham]

If you've driven the trail before, know what the weather has been like recently, and have some info to suggest that the trail remains in good condition then absolutely!

Thing is, there are great fire trails and awful fire trails. They don't consistently stay one or the other, either. Some of the trails near me have just been re-done and I'd happily drive in a Subaru BRZ. Others I wouldn't go down in our Isuzu FTS-800.

[nullc]

There is rock climbing on this particular road, not super severe but something that most passenger cars would be easily hung on.

[devoutsalsa]

I drove a Toyota Prius into some really ridiculous terrain. It was all I had and I really wanted to see some places that weren’t accessible by paved roads.

Here’s what I Learned about driving a 2WD car into questionable situations:

- driving up particularly steeps roads isn’t going to happen because the gearing doesn’t go low enough on the car, and the car won’t have enough power to struggle up the steep grade

- the biggest challenge on any road is ground clearance, so it’s hard to drive over big rocks, rises/drips in elevation, and generally uneven surfaces

- good luck driving through significant mud and water

So if you’re driving along a fire road when it isn’t raining, as long is it’s not too steep, raining, and the rocks aren’t too big, and car with decent tires can probably do it, especially a Subaru.

[rasz]

Locking differential is a fix for poor suspension travel.

If your car can do this

https://wranglertjforum.com/threads/how-much-up-travel-do-yo...

https://wranglertjforum.com/threads/how-much-up-travel-do-yo...

then there is no point locking the diff, wheels will be touching ground at all times, no slippage, full traction.

[kube-system]

Tires can slip while in contact with the ground, as well.

[gorgoiler]

I have say I’ve needed to use difflock on the Defender (another solid axle vehicle excellent at maintaining ground clearance) more times for mud than for ditch traversal.

[alamortsubite]

No, this is only true with equal traction at each wheel, which quite often isn't the case (mud, snow, ice, etc.). Locking diffs are very useful offroad.

[chung8123]

I wouldn't say 4WD vs AWD is the best filter but if that is all they can come up with I guess it works.

Some Audi's have locking differentials and they are AWD.

[morganw]

Audi's with Torsens only lock front-to-back (but then so do a lot of 4WD vehicles). They use brakes to stop slipping wheels so the other side will get torque. A long time ago, they had lockers for the rear for low speed use.

[Daneel_]

Audis don't have transfer cases - that's the key difference between AWD and 4WD.

[partitioned]

My friend has a subaru that he regularly takes on stuff that always impresses the truck and jeep riders. This includes soft sand on dunes, straight up the sides of leaf covered hills, through high rivers with rock bottoms. I think he has lifted it slightly but just about an inch or so with new performance shocks.