Yotrek

What do you guys think??

anoop

What are the tires being used in each case?
Why was the Acura not tested on the same 20% grade? How do we know if the road condition is identical?
More like clickbait. (And it worked on me!)

kurtatx

Not to be an SSFTSX, but which tires are they using? They should all be the same.

Edit: got beaten to it. These comparisons are usually not on the up and up and the results usually tell you about who is responsible for the video.

HotRodW

What do I think? I think when facing a narrow strip of ice on a 30% incline, it's best to straddle it or sidestep it altogether regardless of what AWD system you have.

But seriously, how often does a vehicle encounter drive pavement on one side, and polished ice on the other? So unless you regularly drive in such conditions, the video just doesn't translate to the real world. Plus, there are so many versions of quattro today, that you really need to compare each individually. The Torsen style full time AWD in the Q7 has its advantages, but side-to-side power transfer is not one of them. But put me in deep snow, and it's the system I'd want under me. Having said that, there is no denying that SH-AWD is one of the most capable systems out there ... especially if you take dry road handling into consideration.

On a side note, curious how the camera angle only picked up the [non-applicable] 20% Grade sign when the Lexus and Audi were on the ramp, but the angle is changed to clearly focus on the 30% Grade sign when the MDX is on camera. I'm sure no bias is intended from the Temple of VTec.

RDX10

I have s lot of experience with both SH-AWD and Quattro. In my experience Quattro is very prone to sending too much power to the rear on icy surfaces and with open differentials it starts going sideways and gets all squirrly. SH-AWD never ever did this with me. But that's because it could send power sideways unlike Quattro which uses brakes (unless it has the sport diff).

As for this specific test in question, it really does matter what tires are being used and I don't feel like they gave that Q7 a fair run. However in the case of the Lexus, it has a trash slip and grip system like the 2G RDX. So I'm not surprised it couldn't do it

HotRodW

It was. They just changed the camera angle to imply otherwise.

Yotrek

There's more test and comparison on SH-AWD out there on youtube, most of the test concluded that SH-AWD really shine..I don't know maybe I am wrong..

kboo74656

kurtatx

I do not think you're necessarily in the wrong. I think we need to consider the bigger picture

1. SH-AWD, quattro and ATC are not designed for snow. They are all performance AWD systems
2. Their functions differentiate significantly (quattro, atc are RWD based. SH-AWD is FWD based)
3. How do the sizes of the vehicles compare?
4. Finally, and most importantly, which tires are they running?

One more thing about the 4th one: When it comes to snow, tires are far more important than the number of driving wheels. None of these AWD systems are designed to replace a good set of winter tires. They're performance-centric which is meant to be for handling and grip in normal conditions.

anoop

That's not true.

MI-RDX

All tests were run on the 30% grade hill - the camera angle gives a different impression. If you look at the very beginning of the MDX test (before the video zooms in) you can see the 20% grade hill to the left of the 30%.

HotRodW

So you saw exactly what they wanted you to see. Look again ... they were all filmed on the same 30% incline.

anoop

OK, I get it.

MTD

Thas video is like 6 years old. Im sure the AWD systems have changed since then.

Wander

AWD systems have changed a bit, but what has really changed is computerized brake-based traction control / stability control systems. That is upping everyone's game.

As for the claim that SH-AWD isn't designed for snow... WRONG!

SH-AWD is the successor to the VTM-4 AWD system that was introduced in the 1st-gen MDX with the tagline: "Defeat Winter". It is designed to provide secure traction in inclement weather conditions on-road.

( Of course, if you're serious about it, install snow tires! AWD doesn't do a darn thing to help you stop ).

What SH-AWD is NOT designed for is hard-core off-road, although it's perfectly capable of soft-roading on gravel roads, forest service roads, and such. Just don't take it to the local mud bog without a hefty winch.

Tom2

Biased test, at best. I happen to have both SH-AWD and quattro vehices currently in my garage. I also have a new Jeep Grand Cherokee Trailhawk, which comes with Quadra-Drive II, the most capable 4wd system available on any Grand Cherokee. I can tell you with certainty that the Jeep's 4wd system is superior to both the SH-AWD and the quattro when it comes to snow performance and a test like the one in the video where some wheels have traction and some don't.

As for the quattro vs SH-AWD, I can only say that Audi has several different quattro systems for different vehicles. Most are rear-biased for driving feel and handling. Unfortunately, the newest Audis are starting to move away from the Torsen-based quattro system, which is superior to the newer Haldex quattro systems by a long shot. In all honesty, I don't know from first hand experience how well these new quattro systems perform in low traction situation, but on paper for sure they are inferior to the Torsen quattro systems that Audi has been using for years now. But like all good things, that's coming to an end primarily because of fuel economy concerns. The newer quattro systems are reactive, much like more mainstream AWD systems. They don't engage until slip is measured. The older Torsen quattro systems put power to all wheels all the time and that gave them a slight penalty in fuel economy, so they are slowly disappearing from the newer Audi vehicles.

RDX10

I personally am so disappointed about the changes Audi is making to Quattro. Quattro-ultra is no better than the slip and grip systems on mainstream brands whereas it used to be the top system way back. Right now I put SH-AWD ahead of Quattro-ultra and on par with regular Quattro. FWIW I drove a brand new 2018 Q5 S-Line for a week and was incredibly surprised to find that it drove amazingly well for a front biased system.

As for the system in the Jeep, I think a lot of people overlook it as just some American trash system but it's actually incredibly well sorted. They have been improving it year after year and it's definitely what I'd want offroad of the three mentioned here.

Wander

To be fair, the new "Quattro-Ultra" system is capable of proactively engaging the rear diff under conditions that would be likely to provoke wheel spin, such as during acceleration and hard cornering. The efficiency of that system derives from the fact that the driveshaft is completely disengaged with clutches at both the front AND rear of the driveshaft, when AWD isn't required. Audi claims the system is capable of engaging those clutches and supplying torque to the rear diff in a fraction of a second. But anticipating problems is better than waiting for them to happen, and Audi has that somewhat covered.

https://www.audi-technology-portal.d...tra-technology

OTOH I believe the rear diff in most vehicles with that system is completely open, and brake-based traction control is used to limit wheel spin and re-direct torque. But for some recent Audis, I believe the S-Line has a true overdriven torque-vectoring rear diff. Maybe that's why you liked that loaner/rental Q5 S-Line.

https://www.audi-technology-portal.d...t-differential

As for Jeep, there has always been a bewildering array of 4WD systems available on Grand Cherokees, only some of which are suitable for automatic "full-time" on-highway use. And those safety-oriented AWD-like variants are usually available ONLY on the top trim levels.

Tom2

The current generation Grand Cherokee (known as the WK2) has been around since 2011 and every Grand Cherokee of this current generation has full time 4wd. The base system doesn't have low range gearing though, so that limits it in offroad situations. The top 4wd system like I have on my Trailhawk is optional on some Grand Cherokee trims, but not all of them. But all Trailhawks are automatically equipped with the top level 4wd system by default. And it's really an incredible system. I had a 4Runner before the Grand Cherokee and I'd have to say that the Jeep's 4wd system is every bit as good or maybe a little better than my 4Runner.

4G-Lover

Wrong post, moderators please delete.

Fred Flint

I used to live on dirt roads and there was fairly long steep hill going out, when it snowed it was the easiest way out, I had an A4 Quattro (193) with 4 snow tires, I could go up the hill get to the point where I had zero traction then I could feel each tire in turn get power and it would claw it ways forward, get stuck back up go again. I have my SH-AWD RDX now but will probably have to wait quite a while to actually try it in snow. I also had a Subaru legacy that got stuck going thru snow that had drifted on half the road, it was AWD but it sent all the power to the 2 right tires with no traction.

That video is bad as it showed the Audi sliding backwards with the tires not moving, that to me says it was all ICE.

Wander

In the video, the left tires are on a strip of ice, and the right tires are on relatively dry pavement. It's a severe test of the AWD system's ability to direct torque to the wheels with traction.

That Audi was cheating... it slipped sideways until its left wheels kissed the dry pavement next to the ice strip, then it inched forward back onto the ice. Rinse and repeat.

Your old Legacy probably had open differentials front and rear, and a viscous coupling ( or Torsen coupling ) in the central transfer case. So it could redirect torque front-to-rear, but if one wheel on each end lacked traction it was hosed.

There have been many different versions of both Subaru "Symmetrical AWD" and Audi "quattro"; it's dangerous to make generalizations.

I think you will be happy with RDX's SH-AWD, but if your conditions are challenging you will benefit from winter tires.

skarface

Who's got the best AWD system nowadays?

Wander

That's a loaded question.

What do you value? Off-road capability? Fuel efficiency? Inclement weather safety? On-road handling dynamics? Rally car soft road performance?

I don't think there's any system that aces everything, but I think Acura SH-AWD is top-shelf for handling and slippery paved road conditions.

Madd Dog

I have had cars with the ‘on demand’ AWD, known as slip and grip. I had a Subie with symmetrical AWD, That Subie had been the best foul weather car I had ever owned. This RDX now beats that in my experience. The On Demand was good enough for what I used it for, which was commuting and being able to stay home when things got bad. The Subie could take on fouler weather, both rain and snow. This RDX does everything at least as well as the Subie did, but lets the car handle like a sports sedan when pressed, rather than a brick or an FWD car.

That’s my take, anyway.

ceb

Then there and

skarface

I'd go with the bolded items. I think SH-AWD was the best mix as well. Wondering if any other manufacturers caught up or surpassed Honda/Acura.

HotRodW

SH-AWD was the standout system among the transverse competition, but GKN's Twinster system now offers sophisticated torque-vectoring across the rear axle as well. My personal preference is for an electronic RWD-based system. My BMW's xDrive was stellar. Too bad the car wrapped around it was such a steaming pile of shit.

Wander

Longitudinal drivetrain layout with a center differential/transfer case does allow more flexibility in torque distribution, but often at the expense of packaging efficiency ( huge drivetrain tunnel ), weight, and drivetrain power losses ( hence decreased fuel efficiency ). And if it's combined with live axles that's downright primitive in terms of suspension design.

But for those who crave the traditional RWD feel, it's hard to replicate that in a FWD + "on-demand" rear drive configuration.

Madd Dog

“Hard” being defined as absolutely no way whatsoever.

HotRodW

Transverse applications typically do have packaging advantages, but not always. The new Explorer, for example, has interior space that is competitive for the class despite moving back to a RWD configuration. It's also competitive from an efficiency standpoint. Factor in the better balance and improved maneuverability afforded by the longitudinal drivetrain, and it makes a good case for larger unibody vehicles returning to RWD. Personally, I'm all for it.

Midnight Mystery

Did somebody say "Hard"?

Wander

And also "absolutely no way whatsoever".

Wander

Uh, you're gonna have to convince me that a longitudinal drivetrain is gonna turn an Exploder into a sports car.

RWD is better for heavy-duty towing, but it's also lots better for spinning into ditches in slick conditions. And AWD is optional.

Midnight Mystery

SH-AWD will also put you in a ditch really fast...

If you want RWD go Durango!

Midnight Mystery

Wander

If you overdrive conditions and/or your tires aren't up to the task, anything can slide off the road.

But other things being equal, RWD is more likely to put you in the ditch sideways or a$$-backwards, with the associated increased risk of overturn.

And trust me, rolling an SUV isn't as fun as it sounds.

Midnight Mystery

I'm sure it isn't...


Even with new tires, I've been sideways in the RDX... It has a 52/48 wright distribution, and also has a really stiff suspension, so.........


I've never driven another sideways going car otherwise....


This does arise this question... In the "old days" when almost all cars were RWD, how was this not a major problem, or atleast, treated like one?


I'm almost scared to have RWD in any car now...

HotRodW

I was referring to RWD-based AWD systems, not necessarily pure RWD. AWD is optional on the Explorer, and highly recommended for those frequently driving in slick conditions. Dedicated winter tires even more so.

I never said the longitudinal configuration would turn the Explorer into a sports car. It will be better balanced than the outgoing model, however. Probably don't want to pick a fight with an Explorer ST either.

Wander

It was a huge problem, but there was no alternative. The ditches were well decorated after every snow storm. Overall, cars are much safer today. ( Except for all the electronics to distract us ).

The migration to FWD started with small "imports" ( Japanese ), but continued into darn near everything largely for safety, but also because it made it easier to design more compact, more lightweight cars without the huge, long engine bays needed for big ole V8s. The fuel crisis of the '70s accelerated this.

After a while, only performance cars or pickup trucks were RWD, and they started to add part-time 4WD to pickup trucks and the SUVs that were based upon them. Full-time capable AWD/4WD remained scarce and very expensive for a long time. Pretty much, only "loaded" Jeeps and Land Cruisers had it.