Symmetrical AWD

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We have been sold on Subaru's for years.

We live in the, Central Pennsylvania Allegheny Mountains; which get more snowfall that other areas. I feel you must also put a dedicated, Snow Tire/Ice Tire on for added safety.

With the combination of Subaru and a good tire; that is about as good as it gets, for on road traction and braking safety, in a passenger car.

oldracer
 
We have been sold on Subaru's for years.

We live in the, Central Pennsylvania Allegheny Mountains; which get more snowfall that other areas. I feel you must also put a dedicated, Snow Tire/Ice Tire on for added safety.

With the combination of Subaru and a good tire; that is about as good as it gets, for on road traction and braking safety, in a passenger car.

oldracer

The comparison between several makes and models of AWD/4WD vehicles is interesting.

Subarus are very popular in the Sierra Nevada Mountain Range, esp. in the corridor along I-80 approaching both sides of Donner Summit. I suspect the onboard computer on the newer Subarus can sense when a wheel begins to slip and respond with the proper application of power much quicker and with better control than what human drivers are capable of.

The 1999 Chevy Silverado pickup that I own is equipped with InstaTrac (or Automatic 4wd). The front wheels engage only when the computer senses that the rear wheels are slipping. The computer even reduces engine power when the driver is too heavy on the gas. It slips less, is much smoother and is much easier to turn than standard 4wd.

We haven't had an opportunity to drive our 2013 Subaru Outback 2.5i Premium with CVT and AWP in ice and snow yet. I'm betting that it will be sure footed.

Brute force is becoming a thing of the past.
 
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Brute force is a thing of the past.

But oh so much more fun!

Like I always tell my boss, if I can't get to work in the commuter car (04 Impala, pretty good in snow actually with good tires) - I'm calling in, pulling the lever on the floor of the old wood hauler, and enjoying the rest of my day. Hasn't happened in years though, as much as we like to complain, the highway departments around here do a darn good job of keeping the roads at least passable. Just gotta look out for the other yahoos...

Subarus here are commonly driven by yuppie ski bums, hippies, and old ladies.
 
Pull the manual transfer case into 4-low on my 4Runner, engage lockers, proceed through anything...
 
But oh so much more fun!

Like I always tell my boss, if I can't get to work in the commuter car (04 Impala, pretty good in snow actually with good tires) - I'm calling in, pulling the lever on the floor of the old wood hauler, and enjoying the rest of my day. Hasn't happened in years though, as much as we like to complain, the highway departments around here do a darn good job of keeping the roads at least passable. Just gotta look out for the other yahoos...

Subarus here are commonly driven by yuppie ski bums, hippies, and old ladies.

Glad to hear You have a Highway department that actually does road maintenance. In our area of PA, they plow or treat the roads; when they feel like it. Apparently, you never heard of the 2007 Valentines Day, Snow, on the PA Turnpike and RT.78. This was under Democratic Gov. Rendell's administration. I can't remember what the total death toll was but it was terrible. Penn Dot, wanted to save money by not sending the trucks out. People were stranded for days.



If that above link won't open, go to YouTube, and type in Ken Block STI, or Ken Block, gymkhana, and view some of his videos. Then get back and tell us about the old ladies cars. I could care less about the yuppie ski bums.
 
No doubt the Subaru awd is a pack leader in 4wd technology. I kinda enjoy driving in snow. We bought a ford escape (now an older one) for the Mrs. figuring it would be easier for her to drive in bad weather (automatic 4wd). It is simply amazing. Typically it works like a front wheel drive. Any tire spin, and it automatically transfers power to the rear wheels too. It almost takes the fun out of winter driving. With decent tires, it just goes where you point it. No, it ain't no Subaru, but it goes like nobody's business, and you don't have to be a lesbian to own it. No offense to lesbian Subaru drivers (seem to be a lot of them).
 
But oh so much more fun!

Like I always tell my boss, if I can't get to work in the commuter car (04 Impala, pretty good in snow actually with good tires) - I'm calling in, pulling the lever on the floor of the old wood hauler, and enjoying the rest of my day. Hasn't happened in years though, as much as we like to complain, the highway departments around here do a darn good job of keeping the roads at least passable. Just gotta look out for the other yahoos...

Subarus here are commonly driven by yuppie ski bums, hippies, and old ladies.


Like the Little Old Lady from Pasadena.



 
Its amusing how arrogant city people from the SF Bay Area (who think that they know everything about everything) are always having their 4WDs unstuck from snowbanks and ditches by tow trucks in and around Donner Summit and Truckee, CA. If the slow learners knew how to drive, they wouldn't be getting stuck in the first place. The CHP makes a ton of money ticketing speeders headed from Reno/Truckee back to the Bay Area.
 
A lancer EVO is a stealth scooby, gets my vote, not quite so lairy either
 
We have been sold on Subaru's for years.

We live in the, Central Pennsylvania Allegheny Mountains; which get more snowfall that other areas. I feel you must also put a dedicated, Snow Tire/Ice Tire on for added safety.

With the combination of Subaru and a good tire; that is about as good as it gets, for on road traction and braking safety, in a passenger car.

oldracer

My sister lived outside of Bellefonte on the side of the mountain. She had a Forester with Blizzaks. That car was an utter goat.

She broke it in while going to Cornell in Ithaca, NY. Same story of Blizzaks and being a goat.

I visited her while she lived PA for Thanksgiving a few years ago. There was maybe 2 inches of snow in Bellefonte and she had 6 at her house. That little car flew up that cow path called a road that went to her house.

Sub's are awesome and that's what I will be looking for once my old Accord dies.
 
The way I understand it is that Subaru uses a viscous coupling to control the amount of power delivered to the wheels. The VC is in each diff, when slippage is sensed the viscous coupling solidifies instantly. Its like a liquid clutch.

You cannot drive a vehicle in low loc on dry pavement but you can drive a VC.
 
The way I understand it is that Subaru uses a viscous coupling to control the amount of power delivered to the wheels. The VC is in each diff, when slippage is sensed the viscous coupling solidifies instantly. Its like a liquid clutch.

You cannot drive a vehicle in low loc on dry pavement but you can drive a VC.

I'm not sure exactly how subaru accomplishes their AWD system, but with everything else I know of the VC is in the transfer case. The Jeep quadra-trac AWD system(New Venture/New Process 249 Tcase), and the Jeep "Select-Trac"(New Venture/New Process 242 Tcase) are done this way. The difference between them is that the latter also has options for 2wd and traditional part time 4wd(high and low range). From the point of the Tcase, power transfer/delivery to each wheel is determined by the type of differential used. Locking differentials or spools are a no go on AWD systems, so that leaves either open or limited slip types.

Also, viscous couplers are used because they allow the front and rear wheels to rotate at different speeds. This eliminates the binding found in traditional 4wd systems because the front and rear are not mechanically locked together by gears, or the drive chain found in modern transfer cases. That said, when the viscous coupler fails, the difference in vehicle handling will be noticeable, behaving more like a traditional 4wd. As I understand it, the Subaru's are prone to VC failure, as are the Quadra-Trac systems. From what I can tell Subaru's "symmetrical" system is nothing more than marketing hype based on equal length axle shafts.
 
I'm not sure exactly how subaru accomplishes their AWD system, but with everything else I know of the VC is in the transfer case. The Jeep quadra-trac AWD system(New Venture/New Process 249 Tcase), and the Jeep "Select-Trac"(New Venture/New Process 242 Tcase) are done this way. The difference between them is that the latter also has options for 2wd and traditional part time 4wd(high and low range). From the point of the Tcase, power transfer/delivery to each wheel is determined by the type of differential used. Locking differentials or spools are a no go on AWD systems, so that leaves either open or limited slip types.

Also, viscous couplers are used because they allow the front and rear wheels to rotate at different speeds. This eliminates the binding found in traditional 4wd systems because the front and rear are not mechanically locked together by gears, or the drive chain found in modern transfer cases. That said, when the viscous coupler fails, the difference in vehicle handling will be noticeable, behaving more like a traditional 4wd. As I understand it, the Subaru's are prone to VC failure, as are the Quadra-Trac systems. From what I can tell Subaru's "symmetrical" system is nothing more than marketing hype based on equal length axle shafts.

Can you produce actual documented evidence proving your allegations???? Have you ever considered the idea of traction control/assist by computer? Independent hill climb testing by the U.S. Auto Club is "marketing hype"? The Jeep/Dodge family of AWD/4WD vehicles have a well established reputation for cheap parts, shoddy build quality and poor reliability.
 
Can you produce actual documented evidence proving your allegations???? Have you ever considered the idea of traction control/assist by computer? Independent hill climb testing by the U.S. Auto Club is "marketing hype"? The Jeep/Dodge family of AWD/4WD vehicles have a well established reputation for cheap parts, shoddy build quality and poor reliability.

Can you be somewhat specific? If you are referring to VC failures, then it is nothing new. Speaking with a few knowledgeable subaru enthusiasts provided me with that information, and it is easily verified via the internet. Jeep has poor reliability and quality? Exactly which vehicles are you referring to?

Hill climb testing? :laugh: Considering that probably 95+% of vehicles on the road are sold with an open differential and highway tires, it should be no surprise that any decent AWD with similar tires would perform better if traction was minimal.
 
Over the years I've owned 2 Plymouth and 3 Dodge cars, minivans and full-size pickups. The 64 Plymouth Valiant with a 170 CID Slant 6 engine was the only Chrysler Corp. vehicle that wasn't a pile of crap.

I never could understand why the manufacturers of the Toyota Tundra and the Dodge Dakota marketed their pickups with flatland differential gear ratios and refused to offer limited-slip differentials with gear ratios suitable for hills.
 
I was born and raised in the PNW. I learned how to drive in the middle of winter. No fancy transmissions back then.

In the PNW, we had studded snow tires for winter driving and regular tires for summer. Good tires and a lot of common sense goes a long ways and will get you to pretty much anywhere you want to go. ;)
 
Studded tires did work well but were banned here eons ago, causing too much wear on the pavement. Closest thing we can use would be the tires made with grit imbedded in the tread compound. But the tread compound is soft so they will not last long making them rather expensive in the overall scheme of things.
 
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