A Subaru has none of the above. They make great cars, but they’re not an off road vehicle.
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.
What it does say is that for fire trails, "clearance, strong tyres and suspension travel" are more important, which the Subaru does quality for.
> 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".
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.
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.
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.
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.
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.
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.
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.
Some Audi's have locking differentials and they are AWD.