How stable is all wheel drive supposed to be?


#1

Hey folks,



I have a 98 subaru impreza outback sport. manual trans, 2.2l engine. It’s been crazy snowy today and I noticed that I did fish tail a few times. Is my rear all wheel drive supposed to be evening that out? My back tires are a more worn than my front tires. All together the car performed well but i was worried about the back sliding out.


#2

AWD might feel a little more stable on the road; it depends on how you drive. Keep in mind that AWD will not keep you from sliding into the ditch, but it can help you get out of the ditch.

That said there are three factors you should consider.

  1. You say you have AWD and you have “back tires are a more worn than my front tires” This is a no-no. You can damage that AWD . You need matched tyres. They all need to have the same circumference. See your owner’s manual for specific instructions.

  2. With any car, you want the best tread on the BACK not the front for the best control and safety. Of course with AWD that should be taken care of by rule #1 for anyone with an AWD.

  3. Winter tyres (not all season) will help a great deal. They also help you stop faster and stay on the road, where AWD can’t help with either.


#3

If it’s icy you’ll slide. it’s how you handle it that counts. Can’t tell from here the degree of cornering, speed in , speed out, nor the type of road condintions. But as an example, my own 06 Ford escape hybrid awd . Two days ago it snowed daytime and a lot melted, then by 6:00 the runoff starts to freeze again and is still snowing. As I round a corner ( a neighborhood 4 way stop ) I purposely made a quick left turn, not a gradual arc, to see just how slippery it is. As the car slides slightly I push ON the gas just a tap and it straighted right out perfectly.


#4

That advice IMO may not work for you as older Subarus behave differently than the newer Escape…esp. w/o traction control.

The older Subarus are capable of putting a lot of torque onto the rear wheels (90%), and according to CU can be a little disconcerting at times when cornering when they loose traction. In my Subie, I enjoyed the rear wheel bias.

But, I’m sure it it can be made much worse by the poor tread balance. IMO, it may be even more important with both 4 and awd to have properly rotated tires with equal wear. Otherwise, it’s like driving. in your case, on a patch of ice under the rear wheels all the time as far as the drive system is concerned.

With front drive and abs and poor rear tires, cornering and braking would create problems…you have them all of the time. I would suggest you get new tires and rotate them regularly.


#5

Well, you’re always supposed to have the best tires on the rear, not the front, and this is exactly why. AWD cannot create traction where there is none, and worn tires have very little traction, especially on snow or ice.

You can’t expect AWD to compensate for worn tires or other winter conditions. AWD will help you get going, and is a great help in poor weather conditions, but it is not designed to compensate for worn tires or speeds in excess of what is appropriate for the conditions.

If you need new tires you need new tires. If you’re driving too fast for conditions you’re driving too fast for conditions. Subaru’s AWD, which is the best there is, will not save you if your tires are worn out or you’re driving as if you could defy the laws of physics.


#6

Mr. Meehan has summarized things quite well. To his post, I want to add that if you find that you are fish-tailing, you are driving too fast for the road conditions.

Regarding the value of winter tires, I have an Outback H-6 3.0 VDC, which comes with everything that Subaru offers for traction and control–the Variable Torque Distribution AWD system that is superior to the standard Subaru AWD system, plus traction control, plus vehicle stability control–and I still mount a set of 4 Michelin X-Ice tires for the winter. That should give you an idea of how important winter tires are if you are a driver who is interested in maintaining maximum control of your vehicle.

But, for a moment, let’s return to the topic of your tires. If you are using Bridgestone Potenza RE-92 “all-season” tires–which are factory equipment on many Subaru models–you should be aware that these tires are absolutely USELESS on winter road surfaces. How Subaru ever decided to choose these tires is beyond me, but I have to assume that they were cheap.

Anyway, there is absolutely NO STANDARD for winter traction for so-called all-season tires. Some are okay, some–like those Potenzas–are actually a hazard in the winter.

My advice is to treat yourself to a set of 4 winter tires on their own steel wheels so that you can mount them yourself. The cost of the wheels is offset after a couple of years of avoiding shop charges for mounting and de-mounting both the winter tires and your regular tires on just one set of wheels.

I strongly recommend the Michelin X-Ice tire because of its great traction on ICE as well as snow, thus allowing you to corner safely and to STOP in a shorter distance. In addition, while most winter tires produce “squirrely” handling on dry roads, that is not true with the Michelin winter tire. Most winter tires are noisy on dry roads, but the Michelin is quieter than most of them. And, perhaps most important of all, since winter tires tend to wear rapidly on dry roads, the Michelin X-Ice has much longer tread wear than the competition.

And, even after you treat yourself to winter tires, just try to remember that they don’t make you immune to the laws of physics. Leave a long distance between you and the car ahead of you so that you can avoid them when they do something stupid or they lose control. That saved my brother in his Outback just today when an Impala went out of control in front of him. He safely motored past the Impala in the ditch while he called 911 on his cell phone. If he had been following too closely, he might have hit that Impala, despite his AWD and his winter tires.

Drive safely!


#7

Agee …contrary to an opinion expressed previously, AWD ENHANCES vehicle control and can help you stay out of trouble. Unfortunately because you can drive faster than an front drive, you can drive beyond the “idiot proof” stage and nothing helps.
Good tires all around, drive at speeds you would a FWD and you will have much better steering control and safety.


#8

Consumer Reports did a test last year or so, comparing snow tires on all types of drives. I’ve never had AWD, so I didn’t pay strict attention to that aspect, but–

All cars have four-wheel brakes, and the laws of physics always apply.

Winter tires work on all vehicles. I’ve used them on rwd truck, notoriously bad in snow, and they helped.

Winter tires REALLY help in getting going, and avoiding breaking traction. Physics says that rolling friction is greater than sliding friction. Avoid breaking loose–sliding and spinning tires follow Newton’s laws.

Get snow tires on rims. I got some from a mailorder place, good price, UPS dropped them off right next to my truck. Get four.

Don’t drive too fast. Leave 1000 feet ahead of you if you can. This lets you drive more fuel efficiently too.


#9

According to CU for winter “AWD is better than front wheel drive” and

Their advise is…the same advice from here from all save one.

“Our advice. Consider an all-wheel-drive vehicle if you live in a snowy area or want adUded peace of mind. For maximum traction, equip it with winter tires. In less-snowy areas, front-wheel drive and a set of winter tires should suffice. Mount winter tires on all four wheels for balanced handling. Remove them after winter, since these tires wear quickly on dry roads (plan on about three winters of use). And be sure to opt for ABS on any vehicle.”