True AWD vs. Traction Control >Subaru and Volvo

And are you saying the Volvo AWD isn't ready to give power to any wheels?

Volvo has a traction control system on most if not all cars. It also offers an AWD system on some cars. Understand that they are different systems.

OK, Volvo uses AWD to prevent from getting stuck and Subaru uses AWD as a preventative way to keep from getting stuck. So it would appear that they both use AWD as a way of preventing a car from getting stuck. I do not understand your point here at all.

How do you know that one is better than the other. Hopefully you are not relying on information the adequacy of Volvo AWD from a Subaru dealer. LOL!!

Good, I'm glad they are patented. I'm sure the Volvo AWD system is patented too. But what's your point?

Perhaps you can tell us how an asexual mechanical system could possibly be neutered.

You get what you pay for. If a Subaru is satisfactory to you then enjoy it. Here in the USA the split between comparably equipped Volvo AWD and Subaru 6 cylinder Outback wagons isn't anywhere close to 2x.

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Instead of shooting the messenger (regardless of how biased or self-serving the message he carries from the competing dealer) can anyone point to an objective comparison of the two (or three) systems in question?

Any idea how they are tested or compared?

blurp

"blurp" skrev i en meddelelse news: snipped-for-privacy@4ax.com...

KLIP

If one really wants an off-roader, then buy a Land Rover or a Toyota Landcruiser..

Regards Bjørn J.

There has been no shortage of messages on this topic over the past 2 weeks. Most messages claim to prove Subaru has a better AWD system based on either fuzzy anecdote like his or some hacked home video on Youtube. I suspect they emanate from the same troll. There is no professionally done comparison of the AWD systems between those vehicles that I'm aware of. Absent a good controlled test I think it is safe to only say performance from the two AWD systems will be comparable with one performing somewhat better than the other in certain circumstances. Both have been around for a long time and there have been no consumer complaints about either system not providing ample traction when needed.

The real limitation for either vehicle will be ground clearance. Neither car has an excess of ground clearance and once bottomed out there is no AWD system that will get the car moving again.

Is it true orthodox Jewish people cut a little tip off the exhaust system of every new car in the family or only the blue ones .

Thanks Roadie, an excellent answer! So I suppose then, when comparing the two vehicles, if one is desperate for quantitative analysis then one place to look is road clearance. Possibly also wheelbase/turning circle will affect agility and I suppose curb weight might be a factor.

Other than that you're left with qualitative analysis re: finish, extras, ride comfort.

If available, a long-term road test or year-by-year maintenance cost analysis would also help as would a list of recalls.

blurp.

Yup,

I am quite aware a Subaru Dealer might be a bit biased against a Volvo.

I guess the point is they said their AWD is always on - meaning it does not rely on slippage of a wheel to trigger activity. Volvo is a 'part-time on-demand all-wheel-drive'

i.e. in a turn the AWD is still going whereas on the Volvo - that is not true unless there is slippage. At least that is how it was explained.

Personally I am Volvo biased as it is a solid performer! I like the way they look and perform. Just trying to get more info!

I would love to hear from someone who has both vehicles - and if they notice a difference.

Btw there is a HUGE discrepancy in US prices of cars than in Canada. They are much cheaper in the US! And our dollar is finally worth more than the greenback! Considering the cars are basically the same. Apparently manufacturers are not 'colluding' to gouge Canadian customers. That is why Canadian are headed to the US to buy cars.

There is a $10000 CDN saving in buying a Legacy Wagon. Same thing with base S60.

US retailers are being told NOT to sell to Canadians. Isn't that discrimination?

Can't we all just get along....

Tmuld.

Directing equal power to all wheels all the time would actually seem to be a very inefficient way to operate an AWD system. Under normal driving conditions power is not needed at all wheels. It's been a while, but I believe Subaru uses two kinds of AWD systems. A rudimentary one like the one you describe for cars with manual transmissions and a more advenced eletronically proportioned one for cars with automatic transmissions.

It is my understanding that the Volvo AWD system directs a split percentage of power to all wheels with the front wheels favored under normal no slip conditions. Indeed I found an interesting description on another forum:

"#19, NeoteriX said "...the Haldex system is FWD until the *front* wheels slip,"

That's a common misconception shared even by some automotive writers. It's an accurate description of a simple viscous coupling, but not an electronically controlled AWD system such as Haldex.

Haldex uses parameters such as throttle position, engine speed and engine torque to distribute torque between the front and rear wheels, independent of wheel slip. The torque distribution is matched to how the vehicle is being driven and the driving conditions, whether or not there is wheel slip.

The Volvo implementation normally directs only 5% torque to the rear wheels, for example when you're just crusing at a steady speed on dry pavement. If you then press the throttle hard, Haldex will transfer more torque to the rear wheels in response to that action. It doesn't wait until the front wheels slip. Indeed, the purpose of precharging is to minimize the chance of wheel slip occuring before torque transfer to the rear wheels.

The above is a description of what Haldex calls normal "torque control mode". In addition, if wheel spin does occur such as when driving in snow or other slippery conditions, the Haldex system will act automatically to eliminate it. This is Haldex's "slip control mode."

I owned a Subaru AWD and have owned 2 Volvos with Traction control and one with AWD.

Subaru AWD is a good system but there are scenarios where it doesn't work such as when two wheels on one side are on glare ice on an incline. When Volvo introduced its AWD cars, it took advantage of this bug when they created a demonstration test to compare various manufacturers. Since Volvo had AWD and traction control* both, they passed this test. Since Subarus only came with AWD, they couldn't pass this test.

Subaru responded in 2001 with a Video showing a Volvo struggling to follow a Subaru up a very muddy hill. What they failed to point out but you could hear was that with the Subaru they gently applied the throttle to insure no wheel spin. With the Volvo they gunned the engine to cause wheel spin to make sure there was no traction.

Volvo S40 AWD, S60 AWD, S80 AWD, V50 AWD, V70 AWD, XC70, and XC90 all have Haldex AWD and traction control. It is a very advanced system with an electronic clutch that engages the rear wheels when there is slippage in the front. It is a very fast system and provides true 4WD when slippage occurs and 2WD when there is no slippage.

Some Subarus have viscous clutches which is an old technology that can be unstable when tires do not match. With new tires, it works rather well. Other Subarus use a planetary clutch in the automatic transmission. This functions similarly to the Haldex system but is relatively slow. The Haldex system is faster to react than either of the Subaru systems, so in that sense, Volvo's Haldex system is more preventative and the Subaru system is more reactive.

So the mechanics generalizations have no basis in fact. What is the real difference is that the Volvos have both Haldex AWD and traction control while Subarus have two different types of AWD and some models come with traction control while on others it is an option. Traction control is inheritantly reactive, but most Subarus don't have this system to have it react.

*AWD cars with traction control not only apply power to all wheels, also apply braking to any wheel that is spinning at lower speeds. This works very well on glare ice. On my '95 FWD 850, I was parked on wet glare ice facing the curb on a street with a pronounced crown. I had to back up hill to get out. The traction control worked in reverse and got me out. I was surprised. I thought I would be stuck. So Volvo traction control even works in reverse.

In the strict, dictionary definition of the word, yes. In a practical (and especially legal) use, no.

It's possible that the automakers are colluding, as you claim, but I doubt it (nor did you offer any proof of it). There are dozens of factors. Supply and demand of geographic location for one. Cars are not all priced the same across the US either, you know. Additional costs of shipping is also a major consideration (diesel prices, international law and tax differentiation, etc, etc). And, yes, the strengthing of the Canadian currency has overweighted the prices of the cars (by as much as 17%, I've read).

I know of no law that guarantees a non-US citizen the same rights afforded to US citizens. If an American car dealership refused to sell a car to an American citizen because of age, sex, religion, yada, yada then the US courts could become involved. The reciprocal is probably true in Canada. It may not be fair, but there's no court to hear it. The US isn't going to extend American rights to a non-citizen and Canada has no jurisdiction over American businesses.

Uhhhhh....simmer down there pardner. I didn't make a statement about the unfairness of US and Canadian pricing. Someone else did.

Uhhhhh...yeah that's why I quoted them and included their name at the top of my post. It was off-topic, however, and I apologize.

Let me preface this by saying that I don't know anything, but in my opinion if there's any performance difference between the two systems it will be eclipsed by driver performance, and tire differences.

Me, I have a 92 civic which now sports a limited slip differential, and I (literally) drive circles around the stuck SUVs in the parking lot. (Snow tires vs. all weather tires, not my driver performance).

You're absolutely right, the real unbreakable limitation is ground clearance.

I can second that on the tires, in my experience, nothing makes as big a difference in winter driving as tires. When I put studded tires on my RWD

740 I found I could go just about anywhere. We had a freak snow storm last year that made a huge mess of things, once the dozens of accidents were cleared I had no trouble cruising along past the literally hundreds of abandoned cars. Snow is relatively rare around here so few are prepared and even fewer know what they're doing.