AWD or RWD? (split from new member question)

[Helo58]

How much improvement in MPG are we talking? Kia themselves lists both the AWD and RWD versions at 19/25 - no difference. I would assume the 'real world' differences would be negligible at best. In fact, in a real-world test, Car and Driver found the difference in MPG between AWD and RWD to be 'small to none', and both models exceeded their listed MPG ratings by slight margins.

Better grip is still better grip, no matter how you spin it. Comparing RWD with winter tires vs AWD with summer tires seems kinda nit-picky. If you're going that route, what performance changes would there be for the same two vehicles on dry pavement (RWD with snow, AWD with summer?).

As for the complexity angle - I can't find any hard data on Stinger AWD issues yet. Sure, the 'potential' is there, but is probably marginal at best.

-Tim

Quoting manufacturer's mileage estimates probably isn't the best idea, but short of any quantitative way of making my point, I will simply say that as good as Kia is, they haven't found a way to suspend physics and dynamics laws. There is a whole discipline of automotive engineering devoted to drivetrain losses or efficiency. I assure you that if a RWD and AWD car go on the same drive one behind the other, the AWD will use more fuel. There is no way around that. The word negligible means different things to different people. As you stated, "better is still better."

Again, the AWD doesn't have better grip in all situations due to the additional weight and the tendency for oversteer. On an circular entrance ramp, curvy country backroad or a road course, the AWD will not have better grip. The lighter and more balanced RWD car will.

As for the tires, it is not nit-picky at all. Put the same tires on both cars for every season tested, and the strengths and weaknesses don't change. The point I was trying to make is that the Stinger doesn't come equipped with snow tires. Should you choose to take your summer tire equipped RWD Stinger and place winter tires on it, you would likely outperform the all-season tired AWD in snowy conditions. This point simply means that there is little need for AWD in most situations. No one is arguing that the AWD wouldn't benefit from winter tires as well. That is obvious. Personally, I have an all-wheel drive truck (with ground clearance) for situations where winter tires on my car would not be sufficient. So far, I haven't needed the truck... Are there winter situations where an AWD Stinger would outperform a RWD with snow tires? Sure there are. However, I contend that, for most owners, these frequency of such situations doesn't justify AWD. If you live in an area where the frequency would justify it, you likely have more suitable and dedicated winter transportation (i.e. a truck or beater). Who wants to trash their Stinger driving in 12 inches of snow and salt?

With respect to AWD "complexity," I was simply referring there being a greater number of parts/systems that could fail just because they are installed. Personally, my Stinger will never have an AWD system failure, a power trunk failure, a seat ventilation failure, a HUD failure, a seat memory failure, or a GPS failure to name a few. They aren't installed.

 

[TimS]

Quoting manufacturer's mileage estimates probably isn't the best idea, but short of any quantitative way of making my point, I will simply say that as good as Kia is, they haven't found a way to suspend physics and dynamics laws. There is a whole discipline of automotive engineering devoted to drivetrain losses or efficiency. I assure you that if a RWD and AWD car go on the same drive one behind the other, the AWD will use more fuel. There is no way around that. The word negligible means different things to different people. As you stated, "better is still better."

I did more than just quote the manufacturer. C&D has conducted a real-world test, and their findings seem to support the fact there is really negligible difference between Stinger AWD/RWD MPG. In fact, they used the words 'small to none'. Meaning, in some cases, there won't even -be- a difference. In other cases, the difference is negligible.

Again, the AWD doesn't have better grip in all situations due to the additional weight and the tendency for oversteer. On an circular entrance ramp, curvy country backroad or a road course, the AWD will not have better grip. The lighter and more balanced RWD car will.

I don't know if anyone claimed otherwise. I think most people were simply indicating that in areas with bad weather, rough roads, etc, AWD is superior - which in those circumstances, it is. In places where such adversity isn't a vital consideration, there's less reason for AWD.

As for the tires, it is not nit-picky at all. Put the same tires on both cars for every season tested, and the strengths and weaknesses don't change. The point I was trying to make is that the Stinger doesn't come equipped with snow tires. Should you choose to take your summer tire equipped RWD Stinger and place winter tires on it, you would likely outperform the all-season tired AWD in snowy conditions.

Not sure what your point is here. If both vehicles are equipped with the same tires, AWD will still be the superior choice in inclement conditions.

This point simply means that there is little need for AWD in most situations.

Depends on where you live. In a climate where it rains/snows for significant portions of the year, I would respectfully disagree with your opinion.

-Tim

 

[NickUK]

The AWD Stinger is my 79th car. I'm 53. I swap about every 6 months. Most of my cars have been RWD, several front wheel drive, and a few AWD/4WD. The Stinger is among the best AWD platforms available. Even with AWD, you have a sub five second car with a ton of fun factor in sport mode.

you've had more cars than i've had hot dinners

 

[Tonkabob]

I think 6 months is realistic. Maybe even sooner if Tork's stage 1+ tune ends up working out.

One thing I will say about RWD though is if you are a skilled driver, the RWD will feel more rewarding when pushed to the limit, especially at higher power levels. Maybe not faster, and definitely not safer, but if you can push a 600 rwhp to the limit you will feel like a god

Once turns are involved the RWD is much faster. But it is nice to be able to lay down full power even in the rain in the AWD.
I'm testing the tork 1+ tune and it looks like i may be able to hit 12.1Xs and that is with 4 stock cats and semi quiet mufflers.

 

[Grayt 8]

I did more than just quote the manufacturer. C&D has conducted a real-world test, and their findings seem to support the fact there is really negligible difference between Stinger AWD/RWD MPG. In fact, they used the word 'small to none'. Meaning, in some cases, there won't even -be- a difference. In other cases, the difference is negligible.



I don't know if anyone claimed otherwise. I think most people were simply indicating that in areas with bad weather, rough roads, etc, AWD is superior - which in those circumstances, it is. In places where such adversity isn't a vital consideration, there's less reason for AWD.



Not sure what your point is here. If both vehicles are equipped with the same tires, AWD will still be the superior choice in inclement conditions.



Depends on where you live. In a climate where it rains/snows for significant portions of the year, I would respectfully disagree with your opinion.

-Tim

It doesn't even have to be wet to have an advantage putting power down. Try putting down 365+ HP when the roads are cold and dry.

 

[MerlintheMad]

What I am taking away from the above discussion is that AWD is particularly beneficial to "normal" or commonplace drivers. It allows us to do things that more skilled drivers can do with greater security. This is never more true than when driving through inclement weather conditions.

I came down the one-way stretch of Tuna Canyon yesterday (the only time I've driven it), and that was a bit of a rush; lots of tire marks before the really tight and narrow turns; bumpy, rough spots; and you have to watch for anyone walking or biking up the wrong way, etc. Not very busy when I was on it in late afternoon; only one biker and one pedestrian with his dog. I did not try to "race" down it. And I was glad for AWD. But then, I am not a performance driver. This was just one more incident where personally the feeling of stability was greatly appreciated.

"Understeer". That's what I felt coming down another canyon (Big Cottonwood) a month or so ago, on a prolonged right hand curve with the surface dampened from earlier rain. But the "nannies" instantly corrected it; all I felt was two quick "jabs" of understeer, and the steering was right back to feeling smooth. I felt both alarm and appreciation, if that makes sense. And it also had me thinking about how that would have gone differently had I been a RWD Stinger: would the free wheeling (now heavily loaded) front tires have simply stayed consistent throughout the curve? Because traction was never broken; and the same would have been true in a RWD; probably just without the "nannies" inciting the understeer and correcting what they had incited. Is that what you are referring to?

The AWD divides front end grip between steering and acceleration increasing the chances of overwhelming the front tires resulting in understeer.

 

[Helo58]

I did more than just quote the manufacturer. C&D has conducted a real-world test, and their findings seem to support the fact there is really negligible difference between Stinger AWD/RWD MPG. In fact, they used the word 'small to none'. Meaning, in some cases, there won't even -be- a difference. In other cases, the difference is negligible.



I don't know if anyone claimed otherwise. I think most people were simply indicating that in areas with bad weather, rough roads, etc, AWD is superior - which in those circumstances, it is. In places where such adversity isn't a vital consideration, there's less reason for AWD.



Not sure what your point is here. If both vehicles are equipped with the same tires, AWD will still be the superior choice in inclement conditions.



Depends on where you live. In a climate where it rains/snows for significant portions of the year, I would respectfully disagree with your opinion.

-Tim

Neither Kia or C&D have the ability to suspend physics. I highly doubt that C&D is asserting that their evaluation is scientific. It is likely anecdotal based on time spent with the two cars. Again, the same cars on the same road on the same day doing the same thing, the AWD will get worse mileage. There is no physical way for it to be otherwise. If you can't admit this, then you are simply being argumentative for the sake of it.

My contention has never been that AWD isn't superior in many respects, just that it really doesn't matter that it is superior when a cheaper and simpler choice is adequate for the task . It is like a person with a family of 5 having a massive mental debate over whether to get the van that seats 20 or the one that seats 25 for his family. In this analogy, a RWD car with snow tires seats 7, your AWD with snow tires seats 25. You still only need seats for 5.

If you live where it rains/snows for significant portions of the year, might I suggest another more suitable car for your driving needs or another climate?

 

[MerlintheMad]

If you live where it rains/snows for significant portions of the year, might I suggest another more suitable car for your driving needs or another climate?

Suggest away. I bought the Stinger because I liked what I saw and read about. And the test drive convinced me. It does not benefit a discussion to suggest that a car which was extensively (almost exhaustively) tested from the winters of Sweden to the boiling heat of Death Valley, with the Ring between, is somehow inadequate to securely transport its people through winter conditions, rain, sleet, snow of night, etc. The Stinger is the only car I have. I've never had multiple vehicles for my personal use (we are a two car family, one for me, one for my wife).

 

[Helo58]

What I am taking away from the above discussion is that AWD is particularly beneficial to "normal" or commonplace drivers. It allows us to do things that more skilled drivers can do with greater security. This is never more true than when driving through inclement weather conditions.

I came down the one-way stretch of Tuna Canyon yesterday (the only time I've driven it), and that was a bit of a rush; lots of tire marks before the really tight and narrow turns; bumpy, rough spots; and you have to watch for anyone walking or biking up the wrong way, etc. Not very busy when I was on it in late afternoon; only one biker and one pedestrian with his dog. I did not try to "race" down it. And I was glad for AWD. But then, I am not a performance driver. This was just one more incident where personally the feeling of stability was greatly appreciated.

"Understeer". That's what I felt coming down another canyon (Big Cottonwood) a month or so ago, on a prolonged right hand curve with the surface dampened from earlier rain. But the "nannies" instantly corrected it; all I felt was two quick "jabs" of understeer, and the steering was right back to feeling smooth. I felt both alarm and appreciation, if that makes sense. And it also had me thinking about how that would have gone differently had I been a RWD Stinger: would the free wheeling (now heavily loaded) front tires have simply stayed consistent throughout the curve? Because traction was never broken; and the same would have been true in a RWD; probably just without the "nannies" inciting the understeer and correcting what they had incited. Is that what you are referring to?

AWD does not offer you more "stability," it simply offers varying amounts of thrust at all 4 wheels rather than two. You will likely only notice a benefit when accelerating (inclement weather or otherwise). For stopping and turning, AWD offers no direct benefit. The "nannies" that corrected your understeer on the canyon road would have done the exact same thing on the RWD car. Stability control has been mandatory on all US cars since 2012. I suspect that the AWD and the RWD would have both understeered in the situation you mentioned, with the AWD being the one more likely to understeer due to inertial forces acting on the greater weight of the front axle in the AWD car as well as any drive forces if you were on the gas at the time. If a RWD car slides the front tires in a corner (understeer) and loses traction, AWD is not going to increase or restore this traction. The adhesion limit of the tire has been exceeded and is only restored when the forces acting on it are reduced, not simply changed.

 

[MerlintheMad]

AWD does not offer you more "stability," it simply offers varying amounts of thrust at all 4 wheels rather than two.

Which produces/offers, what, exactly, if not a more secure/stable ride? Handling is what we are talking about. Granted, what goes into traction and stability control plays a larger part in this. But drive to the front wheels is added to traction and stability control. If you are off the gas rounding a downhill curve (like my RL scenario) and going a bit too fast, and you know that touching the brake is a no-no, will the "nannies" apply power to any of the wheels to help "power" through the curve? A combination of power and brake? My understanding is that the moment by moment nature of the "nannies" does all three: power, brake and suspension stiffness (or lack) to meet the conditions. I don't see how AWD can come up short on this, since power being possible to the front wheels adds a third component to keep the car "stable", or under control if you will.

 

[Helo58]

Suggest away. I bought the Stinger because I liked what I saw and read about. And the test drive convinced me. It does not benefit a discussion to suggest that a car which was extensively (almost exhaustively) tested from the winters of Sweden to the boiling heat of Death Valley, with the Ring between, is somehow inadequate to securely transport its people through winter conditions, rain, sleet, snow of night, etc. The Stinger is the only car I have. I've never had multiple vehicles for my personal use (we are a two car family, one for me, one for my wife).

I didn't seriously intend to suggest anyone relocate over transportation needs, however I live in a state inundated with "snowbirds" who have done exactly that. The testing and vetting that you mention likely had more to do with Kia ensuring the car held up for the warranty peeriod than Kia ensuring the Stinger was a capable snow warrior. I never suggested that an AWD Stinger is "inadequate to securely transport its people through winter conditions...." I merely contended that a RWD Stinger with dedicated snow tires is just as capable for completing daily driving tasks in winter conditions.

Maybe this will help. Pictures and videos always make a point clearer, as do authorities on the topic.

Do You Really Need AWD in the Snow? - Consumer Reports

 

[Helo58]

Which produces/offers, what, exactly, if not a more secure/stable ride? Handling is what we are talking about. Granted, what goes into traction and stability control plays a larger part in this. But drive to the front wheels is added to traction and stability control. If you are off the gas rounding a downhill curve (like my RL scenario) and going a bit too fast, and you know that touching the brake is a no-no, will the "nannies" apply power to any of the wheels to help "power" through the curve? A combination of power and brake? My understanding is that the moment by moment nature of the "nannies" does all three: power, brake and suspension stiffness (or lack) to meet the conditions. I don't see how AWD can come up short on this, since power being possible to the front wheels adds a third component to keep the car "stable", or under control if you will.

Your understanding of AWD, and possibly others, seems to assume that AWD overcomes the traction limitations of a tire that has already exceeded its traction limit. The "nannies" will never apply power in a turn if you have entered the turn too fast. The ESC will apply BRAKING forces to tires with traction according to the algorithm most suited to bringing the car back to a point where it behaves in a manner commensurate with driver inputs. Applying power in such a situation would only make the problem worse, drastically worse. I think you know this because you stated that touching the brake is a no-no. Touching the brake and gas both accelerate the car, one positively and one negatively. If you can't hit the brake, then you likewise can't hit the gas and expect a different outcome. Both will exacerbate the problem. The key difference is that the ESC applying braking force to tires with traction independently, the driver (brake pedal) controls all 4 simultaneously. In the case of a slide, the software will always reduce speed and never increase it.

 

[TimS]

Neither Kia or C&D have the ability to suspend physics. I highly doubt that C&D is asserting that their evaluation is scientific. It is likely anecdotal based on time spent with the two cars. Again, the same cars on the same road on the same day doing the same thing, the AWD will get worse mileage. There is no physical way for it to be otherwise. If you can't admit this, then you are simply being argumentative for the sake of it.

No one claimed they suspended physics. What is being claimed is that, in an identical test between the two models, the MPG differences were 'small to none'. I am not sure why you are having a difficult time understanding this. Their real-world test was conducted to give typical end-users an idea what to expect in real-world conditions, nothing more. Typical end-users don't care about the 'science' - they care about the results. Not sure why it bothers you to accept that the difference is negligible, as I've stated several times. Just -how much different- the MPG is for the average driver will vary from person to person, of course, based on a number of factors. A lead-foot RWD driver might very well have lower MPG than a conservative AWD driver - the point is, their base MPG is so close that even Kia rated them identically, and a reliable publication found the differences 'small or none'. Get it?

My contention has never been that AWD isn't superior in many respects, just that it really doesn't matter that it is superior when a cheaper and simpler choice is adequate for the task . It is like a person with a family of 5 having a massive mental debate over whether to get the van that seats 20 or the one that seats 25 for his family. In this analogy, a RWD car with snow tires seats 7, your AWD with snow tires seats 25. You still only need seats for 5.

'Better is better', right? I have to wonder if you've ever actually driven RWD and AWD vehicles in inclement weather?

If you live where it rains/snows for significant portions of the year, might I suggest another more suitable car for your driving needs or another climate?

Using that logic, if you're so concerned about the 'complexities' (i.e AWD) of a modern vehicle, might I suggest that for your next vehicle purchase you simply go with the base model Forte so that you can sleep better at night?

-Tim

 

[Menissalt]

Touching the brake and gas both accelerate the car

We're getting dangerously close to a physics lesson on acceleration and deceleration and how most people use these terms wrong, lol. I can get behind this.

_______________
I think the OP has a ton of great information here, more than enough to help make their decision. They've already said they're going to drive both before deciding.

 

[jmf_tracy]

I don't understand the lack of AWD love around here.
AWD is an upgrade over RWD, AWD is not inferior.
Look at high end sports car like Nissan GTR, Audi R8 & RS series - are only available in AWD - there is no RWD option.

 

[MerlintheMad]

Maybe this will help. Pictures and videos always make a point clearer, as do authorities on the topic.

Do You Really Need AWD in the Snow? - Consumer Reports

"But most AWD drivers don’t think of adding winter tires. According to our survey of 54,295 subscribers who drove AWD or 4WD vehicles in the snow for more than six days last winter, less than 15 percent equipped their vehicles with winter tires. The rest kept rolling on their all-season tires and took their chances."

This is telling: it's because most drivers feel secure enough to justify those few days per winter when the conditions are "dicey". The rest of the time their A/S "weather the storm" by offering that feeling of being in control. If five out of six drivers drive safely on A/S that says something good about the quality of A/S tires generally, and AWD specifically; the combination works for the majority of drivers.

The difference in stopping distance (700 vs 300) on A/S or winter tires is only a test, not reality. In icy conditions (or a threat of the same); on snow packed roads; especially at night; I will not be doing anywhere near 60 MPH, especially in traffic. Someone who has opted to keep on their A/S (me) will already know up front that they need to drive slower and brake earlier and softer to get the maximum out of their tires. They don't expect to "compete" with winter tire equipped vehicles. AWD is an enhancement, not a "silver bullet" against the snow. And as also pointed out, A/S are good enough in areas with aggressive plowing and road maintenance through the winter.

 

[Helo58]

No one claimed they suspended physics. What is being claimed is that, in an identical test between the two models, the MPG differences were 'small to none'. I am not sure why you are having a difficult time understanding this. Their real-world test was conducted to give typical end-users an idea what to expect in real-world conditions, nothing more. Typical end-users don't care about the 'science' - they care about the results. Not sure why it bothers you to accept that the difference is negligible, as I've stated several times. Just -how much different- the MPG is for the average driver will vary from person to person, of course, based on a number of factors. A lead-foot RWD driver might very well have lower MPG than a conservative AWD driver - the point is, their base MPG is so close that even Kia rated them identically, and a reliable publication found the differences 'small or none'. Get it?



'Better is better', right? I have to wonder if you've ever actually driven RWD and AWD vehicles in inclement weather?



Using that logic, if you're so concerned about the 'complexities' (i.e AWD) of a modern vehicle, might I suggest that for your next vehicle purchase you simply go with the base model Forte so that you can sleep better at night?

-Tim

Tim, I get it and have been "getting it" ever since I learned that scientific and repeatable tests are the only valid ones for making claims. It is called substantiation. EPA mileage claims on the widow sticker rarely reflect real world results. Furthermore, if you remember correctly, about 5 years ago Kia/Hyundai got caught overstating EPA mileage estimates and had to pay a $41.2 million dollar settlement for the offense.

As for the science, ignoring it doesn't make it not true. AWD vehicles will get lower gas mileage when tested side by side with the "same" RWD vehicle. Your claim that C&D said it was the same during their testing is like saying you beat Lebron James at a game of horse so that means you are a better basketball player.

If you had read my earlier posts, you would have seen that I do in fact have an AWD truck. I have driven it in inclement weather and it was great. You know what else was great, my wife's 2WD car in the same conditions on snow tires. I have to wonder if you've ever actually driven a 2WD car on snow tires.

If the Forte came with a 3.3L TT, RWD and seating for 5, I would consider it. BTW, I sleep great at night.

 

[Menissalt]

I don't understand the lack of AWD love around here.
AWD is an upgrade over RWD, AWD is not inferior.
Look at high end sports car like Nissan GTR, Audi R8 & RS series - are only available in AWD - there is no RWD option.

Most of this thread has been pro AWD. It just depends on what someone wants. RWD is 194 pounds lighter, this makes a difference. RWD also has a limited slip differential, the AWD doesn't. The AWD and RWD both feel a little different to drive if you're the type of person to pick up on it.

There are valid points to both sides and they're being represented pretty well here.

 

[Helo58]

"But most AWD drivers don’t think of adding winter tires. According to our survey of 54,295 subscribers who drove AWD or 4WD vehicles in the snow for more than six days last winter, less than 15 percent equipped their vehicles with winter tires. The rest kept rolling on their all-season tires and took their chances."

This is telling: it's because most drivers feel secure enough to justify those few days per winter when the conditions are "dicey". The rest of the time their A/S "weather the storm" by offering that feeling of being in control. If five out of six drivers drive safely on A/S that says something good about the quality of A/S tires generally, and AWD specifically; the combination works for the majority of drivers.

The difference in stopping distance (700 vs 300) on A/S or winter tires is only a test, not reality. In icy conditions (or a threat of the same); on snow packed roads; especially at night; I will not be doing anywhere near 60 MPH, especially in traffic. Someone who has opted to keep on their A/S (me) will already know up front that they need to drive slower and brake earlier and softer to get the maximum out of their tires. They don't expect to "compete" with winter tire equipped vehicles. AWD is an enhancement, not a "silver bullet" against the snow. And as also pointed out, A/S are good enough in areas with aggressive plowing and road maintenance through the winter.

I can only lead you to water, I can't make you drink. The video clearly showed the benefits of a winter tire equipped 2WD car and suggested that it is equivalent or superior to an AWD car on summer or all-season tires in all driving parameters with the exception of acceleration. The test I referenced was conducted by Consumer Reports and was done in a scientific manner. There are many other tests available for viewing. Tire Rack, for one, has a great video comparing vehicle dynamics at lower speeds. I doubt that you or others will be swayed, but here is the video...

 

[westcoastGT]

I can only lead you to water, I can't make you drink. The video clearly showed the benefits of a winter tire equipped 2WD car and suggested that it is equivalent or superior to an AWD car on summer or all-season tires in all driving parameters with the exception of acceleration. The test I referenced was conducted by Consumer Reports and was done in a scientific manner. There are many other tests available for viewing. Tire Rack, for one, has a great video comparing vehicle dynamics at lower speeds. I doubt that you or others will be swayed, but here is the video...

need to get past the issue of Winter driving ( ie snow/ice ) AWD provides a benefit in all seasons ................the new BMW M5 .............XDrive ???? they didnt do that for winter .......at all .