Mainstream Large Sedans Comparison

havalongavalon

... with my Avalon. If I need to speed up quickly while cruising at 55 I just shift from "D" to "S" (manual or sport shift). This cancels any recently learned driving pattern. It allows Mr. Hide (aka 0-60 in 6.5) to take over from Dr. Jekyll (31 mpg) instantly, smoothly, with NO hesitation as soon as I give it more gas.

Don't sales people routinely inform prospective buyers of this simple feature?

tjc78

I wasn't told about this feature when I bought my car. I almost never take it out of "D" and it responds instantly to any throttle input I give it. I know I am going to start trouble here with the Lucerne owners, but from what I remember from my test drive the tranny in the Lucerne didn't shift as quickly or as smoothly as either my 03 or 06 Avalons, and the Norhtstar V8 didn't give the kind of performance I expected. I just think that people that have driven Buicks for a while like the powertrain in the Lucerne because it is something they are familiar with. Like I have said before its not bad... there are just better alternatives (IMO).

louiswei

I agree with tjc78, I really think that it's going to take some getting used to for the long-time OHV owners to adjust to those new generation OHC engines. However, for a person whom learned to drive a car with OHC engines then it's not a big deal. As matter of fact, I think those OHV engines on the rental cars I got react oddly every time.

pat

One has to be logged in to post. There is a bug the software guys are chasing that occasionally makes a poster's name not be attached to a post. It is not in the poster's control, unfortunately.

pat

What does your owner's manual say? That's what you need to be going by.

It was my understanding that Avalons call for regular, and when regular is specified, there is no benefit to burning premium. I do not have an Avalon so don't listen to me, listen to your manual.

louiswei

As far as I know, NONE of the Toyota products required premium (91 or better). However, they do recommend premium for improved performance.

If premium is not required then it wouldn't hurt the engine by using regular fuel. The fact is that EVERY SINGLE ENGINE out there right now (Toyota or non-Toyota) will have an increase in performance by using premium fuel.

billwfriend

I'm fairly certain these are program cars, hence the 'great price'... I've actually had good luck with program cars in the past, just gotta be choosy when looking at them.

3.5 rated 21/32
3.9 rated 19/27

Still better then the Pacifica's comperable 18/25 and 17/23 ratings.

captain2

I resent being told that I must re-learn just how to drive!
You didn't say whether you have the 3.8 or Northstar, but in any case, the last bastions of older technologies. I agree with your statement, but, unfortunately, this is not something that you will have any choices on - computer 'assisted' driving is here to stay - already here in many cases, and shortly in others. The old OD 4 speeds in GM products will soon be replaced by 5/6 speeds at the cost of some drivability but with a bonus of a mpg or two. Enjoy your Lucerne while you can.

gamleged

It was mentioned that the Avalon seems to "reset" it's learned shifting behavior by the driver moving over into "manual" then back into automatic. I tried that yesterday on my Azera Limited and it did seem to work, as I believe I had an immediate loss of delay (and the delay isn't that much anyway) the next time I leadfooted a bit...

havalongavalon

Interesting. In the Avalon I usually shift from D to S and just leave it there. In S it still shifts automatically when needed, but it ignores recent history so it behaves more responsively to the gas pedal.

It makes sense that shifting from D to S and back to D should also cancel the memory, but this is more like a memory reset & restart. In D it would be "learning" again, so a while later it may again resist a sudden change in your driving style. That's why I just leave it in S.

bobw3

http://www.iihs.org/ratings/summary.aspx?class=20
Best is the Ford Fivehundred

Even beats all but one of the luxury large cars tested.
http://www.iihs.org/ratings/summary.aspx?class=10

louiswei

Yeah, but all other competitors offer standard side airbag but it's option on the 500 and the Charger/300.

bobw3

Okay, but with the optional side airbags the Ford 500 is ranked #1 for safety. Point is if someone is looking for the safest car, get the Ford 500 (with the optional side airbags). Yes it would be nice if they were standard, but that doesn't change the outcome of the safety tests.

texases

What's the basis for stating "EVERY SINGLE ENGINE out there right now...will have an increase in performance by using premium fuel"?

louiswei

Engines will benefit from using cleaner fuel. Simple as that.

bobw3

Does higher octane provide better MPG and/or lower emmisions?

imidazol97

>Engines will benefit from using cleaner fuel.

Do you have proof the higher octanes are "cleaner"? IOW if I'm buying Shell regular, it's dirty and if I pay the extra for Shell super premium V5 or whatever it's call, it's cleaner?

I thought all fuels had the same detergents in regular and the 91-92 versions. In fact, burning the premiums in regular motors actually burns slower and leave behind more carbon. The premium doesn't really burn better and fouls spark plugs faster, e.g.

captain2

one of the greatest marketing scams of all time - all gas is the same from the same tank and/or trucks, whether from that Shell branded station or from your local conveninece store! Additives may be different but are, as a rule, inconsequential, despite the claims.

quietpro

only benefits engines designed to make use of it. Some of the "modern" engines, including my "old-tech" OHV 5.3L Chevy, adjust timing on the fly to utilize the higher octane when it's present but retard the timing to compensate when it isn't. If the engine isn't designed with this technology and simply calls for regular fuel, you're wasting your money and increasing pollution by running the higher octane fuel.

As for the additives in the fuel, they do vary by brand and in some cases, by grade (Shell advertises better cleaning in their premium fuel). I personally don't trust cheaper fuels. A few pennies per gallon doesn't compensate for the couple hundred dollars it will cost to have your injectors cleaned.

Simply put, you should buy the grade of fuel recommended in your owner's manual as long as the vehicle runs well on it. As your engine wears and gets dirty, you may start to notice the "knocking and pinging" of the engines of years past. In that case, get some maintenance and all should be well again.

As Captain2 states, high octane marketing is one of the oldest tricks in the book. It's your money but you're throwing it away on high octane fuel if your car isn't designed to make use of it.

quietpro

He did specify that he was shopping for a V-6. As for the "last bastions" comment, the Northstar is aged but it is the same DOHC, VVT technology you all keep bragging about. As a matter of fact, it's been around longer than most of the Japanese versions. The "funny" part about it is that while GM was one of the earliest manufacturers of this technology, they didn't push it because their customers preferred the performance of the "old" technology, at least in value. Cadillac (and later Olds, Pontiac, and Buick) buyers paid a hefty premium for newer technolgy but the performance advantage is questionable.

quietpro

That's why I just leave it in S.

Doesn't that negate the "superior" technology and make your vehicle drive the way the buyers of American branded vehicles prefer? I suppose you still have the option of choosing between the styles but why pay extra for technology if you don't like or use it?

tjc78

The Northstar in the Lucerne (or the older Bonneville's) is not VVT. Only the rear wheel drive varients of the engine get the VVT.

havalongavalon

Probably because it's impossible to provide both optimal fuel economy and high performance at the same time. The Avalon seems to be designed to adapt to your personal style when in "D" but for this to work perfectly, you need to be pretty consistent. If you are a more spontaneous driver this can confuse the controller and cause occasional "hesitations." So you have the choice of disabling the learning of unwanted patterns, by shifting into "S". This gets you more freedom to vary your driving style but at the expense of sub-optimal fuel economy. Your choice.

Personally, I like it and I use it. I usually drive in D when in steady traffic and shift into S when I want to suddenly move ahead of the pack. Especially on steep hills.

quietpro

The Northstar in the Lucerne (or the older Bonneville's) is not VVT. Only the rear wheel drive varients of the engine get the VVT.

That is correct. I never stipulated a particular model, only that the technology exists in GMs engines and has been there for a very long time.

shipo

"The fact is that EVERY SINGLE ENGINE out there right now (Toyota or non-Toyota) will have an increase in performance by using premium fuel."

Bzzzt! I'm sorry, that is incorrect. Unless an engine has an ignition system that can keep the spark advance just shy of the edge of disaster (the point that yields the best power and best fuel economy for any given fuel), regardless of fuel grade, using a higher octane fuel than recommended will degrade both performance and economy.

Think about it this way, Premium slows down or delays the formation of a fully organized flame front that moves across the combustion chamber in all directions from the spark plug(s), and that in turn delays (from a mechanical timing perspective) the point of maximum (or peak) pressure (PPP). As a general rule, the PPP should occur at about twenty degrees after TDC (plus or minus a few degrees, depending upon engine design), which is the starting point of greatest mechanical advantage inside the engine. If the Peak Pressure Point (PPP) occurs too early (typically from using a fuel of too low of an AKI), much potential energy is lost pushing down on an almost vertical (to the path of piston travel) crank throw, and often leads to severe detonation. If the PPP occurs too late (typically from using a fuel of too high of an AKI), then the piston travels beyone the point where it can efficiently convert energy into twist (or even bottoms out) with a still viable combustion charge in the combustion chamber. As a result that potential energy remaining in the cylinder after mechanical advantage is lost goes out the exhaust valve. Either way, power and economy suffers.

True, there are some engines that call for Regular that can retune themselves to exploit some of the potential advantages of Premium, however, only engines designed to burn Premium can take full advantage of Premium fuel.

Best Regards,
Shipo

kwk1

True on the premium fuel.
I have a '94 Caprice with a 350 LT-1, and it runs on Regular fuel.
If I want to take advantage of Premium fuels, I need to have the ECM(computer) re-programmed for it.

plekto

Engine 1: 220 lb-ft/s 2500 RPM and takes 5 seconds to get to that RPM

Engine 2: 250 lb-ft/s 4800 RPM and takes 4 seconds to get to that RPM

***
More like:
Engine 1: 220 lb-ft/s 2500 RPM and takes 1.5 seconds to get to that RPM

Also, the beauty of old technology is twofold. One, if it's not broken, why "fix it"? Secondly, it's adequate enough to be sure, but TONS cheaper to fix.

Your choice. $1600 for a GM tranny or $3500 for the one in the Avalon or Camry. And last I checked, parts for most Toyotas are much more expensive than for a Buick.

And the Lucerne is a sweet ride. It's no asphlt-burner, but in city traffic, it responds very quickly compared to most V6s. Sweet V8 exhaust sound as well.

Now if they would put that engine in the new CTS.. Wel, I can dream I guess.

louiswei

Engine 1: 220 lb-ft/s 2500 RPM and takes 1.5 seconds to get to that RPM

Trust me, the OHV I had on my Impala rental wasn't going to reach 2500 RPM in 1.5 seconds. I know this because I was flooring it and had my eyes on the tachometer the whole time because I want to compare it to my 2GR-FSE.

On the 2GR, if one floors it, it will reach over 5000 RPM in first gear in less than say 3 to 4 seconds. However, on the Impala, the engine will make loud noise but the tachometer needle isn't really going any where.

tjc78

I know you didn't mention a model, but we talk about the Lucerne a lot in here and didn't want anyone to get the wrong idea. Why on Earth GM wouldn't spend the few extra bucks on Buick's flagship is beyond me. I think the Northstar with VVT is something like 320+ HP. Maybe even better yet make a true "sports" model with it as an option.

tjc78

"Trust me, the OHV I had on my Impala rental wasn't going to reach 2500 RPM in 1.5 seconds"

I rent Impalas quite frequently and can testify to this as well.

imidazol97

>Engine 1: 220 lb-ft/s 2500 RPM and takes 5 seconds to get to that RPM

Engine 2: 250 lb-ft/s 4800 RPM and takes 4 seconds to get to that RPM

I gave up reading that simplistic exaggeration in an attempt to show that something the poster didn't like JANG (just ain't no good).

I watch the tach on my little old OHV 3800 as I leave stop signs and it jumps to 2000-2500 quickly as it spins up to the torque converter operation speed. But I realized that this is the old "I hate US brand cars with some technology that's not what is in the car brand I have chosen to drive syndrome." And everyone is welcome to their opinion or favorite; and I am too.

Motor rev rates depend on flywheel mass and transmission gear ratios and on axle ratio along with the torque converter characteristics. Ideally each has been picked to optimize the engine's strengths. \

In my old-fashioned 3800 which has been modernized through the couple of decades OHV motor will deliver the mileage in a true full-sied 6 passenger car both on long and short trip driving.

I'm happy. Drive what you want.

louiswei

I'm happy. Drive what you want.

Exactly, I am also sick and tired to read some posts saying that the OHC engines are weak in the low RPM region. That's why I made up the 2 generic engines just to show the difference in design between the OHC and OHV.

Also, you are mistaken about us hating the US brand cars with the OHV engines. Like I said before, some people grew up and learned to drive with OHV cars so obviously they will be more comfortable with it. However, people like me, we grew up driving OHC cars so clearly we'll favor it over the OHV. Nothing's wrong with either one, it's purely personal preference.

However, for me at least, I'll choose new technology over an old one on any given day. Especially if I am about to drop over 30 large on a brand new car.

captain2

well back into the 90s, the Northstar I believe, and certainly one of GMs best efforts, it is, BTW, a total antithesis of traditional "Detroit" engines (esp the V8s), as you seem to suggest. Why they didn't take some of that experience gained with the Northstar, and apply it to the V6s may be a function of financial capabilities as opposed to engineering ones. The new 3.6 first available in the CTS and now in the Aura, seems to be a step in the right direction, but still short of the best the competition has to offer. The Toyota 2GR is continuously variable on both intake and exhaust sides (another few steps in sophistication (and efficiency)), and besides pulling a 3600 lb car to 60 in six seconds, it can also get 30 mpg rather easily out of a tank of gas - that is what makes it worth 'bragging' about and a remarkable achievement.

captain2

Now if they would put that engine in the new CTS
are you forgetting the CTS-V, 400 hp/400 lb. ft. LS6 engine? Or even the GTO with a similar powertrain - not the Northstar but a more traditional pushrod design. Big V8s something that "Detroit' DOES know how to do...

captain2

Why on Earth GM wouldn't spend the few extra bucks
I think there are 2 answers to your question:
1) GM just got done losing $10 billion last year - they don't have the money
and,
2) Putting 300+ hp to the front wheels creates a new set of problems - torque steer. Drive an Impala SS or a Maxima.

gamleged

"Putting 300+ hp to the front wheels creates a new set of problems - torque steer. Drive an Impala SS or a Maxima."

A word for the Azera limited: Its 263 hp to the front wheels produces zero torque steer. As some reviews I've read stated, "You really can't tell it's front wheel drive!"...

shipo

A word for the Azera limited: Its 263 hp to the front wheels produces zero torque steer. As some reviews I've read stated, "You really can't tell it's front wheel drive!"...

Not possible. Take the Axera (or any other "Torque Steerless" FWD car you care to choose) and sit at a stop light waiting for a left turn. Mash the gas, turn the wheel and PRESTO, you get torque steer.

Best Regards,
Shipo

louiswei

Not possible.

It is possible and there are other cases besides Azera such as the 2007 Nissan Altima and 2007 Acura TL-S

captain2

if your point is that torque steer MUST exist as a matter of the laws of physics, then point taken. Engineering suspension geometries, throttle programs (as in the new TL-S), or even monkeyng around with tire sizes (the GP) all can serve to hide TS very well. The Avalon I drive, I couldn't get a perceivable tug of my sterring wheel if I wanted to and heaven knows it has the power to do it. My wife's Altima 3.5, however, a different story.

shipo

"It is possible and there are other cases besides Azera such as the 2007 Nissan Altima and 2007 Acura TL-S"

Been there, done that, got the Tee-Shirt. Like it or don't, I was able to get the Altima and the TL-S (with the 6-Speed) to generate a fair amout of torque steer.

Best Regards,
Shipo

louiswei

So you drove both the Altima and TL-S?

How does the 2 compare to each other? Was the Altima's transmission smooth at the start? What does it happen when you floor it?

shipo

"If your point is that torque steer MUST exist as a matter of the laws of physics..."

Yes, that is part and parcel of what I was attempting to say.

"Engineering suspension geometries, throttle programs (as in the new TL-S), or even monkeyng around with tire sizes (the GP) all can serve to hide TS very well."

Admittedly torque steer has been much mitigated since FWD cars first hit the scene (geez, my ~85 hp 1979 VW Scirocco had gobs of torque steer), however, it hasen't been altogether eliminated. I've test driven two Acura TLs (one was a TL-S), and both had 6-Speed manual transmissions. In both cars I was able to generate torque steer turning left onto a freeway ramp from a traffic light controlled surface street where two lanes turn onto the ramp but the ramp itself only has one actual lane. In my RWD sedan I'm able to nail the throttle and get to the open ramp with the front wheels doing the turning and the rear wheels doing the accelerating. Simple, straight forward and effective. The same torque steer thing held true for the 2007 Altima that I drove last week.

The second scenario where I've uncovered very noticeable and annoying torque steer on all three cars is a little more difficult to explain. There is a fairly long grade that I routinely traverse that has a huge amount of heavy truck traffic. Given the roughly westerly facing orientation of said grade, the tarmac is exposed to the hot afternoon summer sun and gets somewhat soft. Combined with all of the truck traffic, the tarmac has become deeply rutted. Not rough ruts mind you, more like a deep (maybe 6" deep at the deepest) and smooth "U" shaped trenches where the tires typically roll, not at all unlike an old country lane where there are two ruts for tires and grass growing in between. When climbing that hill in all three cars and holding steady speed the FWD/rut combination causes the cars to alternately attempt to climb first one side of the trench, and then once corrected for with the steering, the car to attempt to climb the opposite side. Said another way, it was impossible to drive any of the three straight up that grade without wandering left-right-left within the lane itself. I've had that problem in every FWD vehicle I've driven up that grade, and yet I've never had even a hint of wandering in any RWD car or truck that I've had on the same piece of road.

Best Regards,
Shipo

shipo

So you drove both the Altima and TL-S?

Unfortunately they weren't really comparable as the Altima I drove was a 2.5 liter 4-Banger version (see below).

How does the 2 compare to each other? Was the Altima's transmission smooth at the start? What does it happen when you floor it?

I presume you're referring to the CVT transmission. As I am allergic to automatic transmissions, I searched for a dealership that had a 2.5 S 6-Speed in stock (local dealer, nyet, dealer two towns over, da), as such, I suspect that my answers aren't going to be what you are looking for. BTW, don’t get me started on Nissan's stupid and arbitrary ordering policies that prohibit 6-Speed cars from being built with the V6 or Leather seats or other goodies. Grrrr. :mad:

Best Regards,
Shipo

germancarfan1

Your choice. $1600 for a GM tranny or $3500 for the one in the Avalon or Camry. And last I checked, parts for most Toyotas are much more expensive than for a Buick.

Your choice: $1600 to replace the GM tranny when it fails at 60K or $3500 for the Toyota tranny when it fails (if) at 180K.

Tough choice.

shipo

Not that I'm a big fan of GM vehicles, however, based upon recent history, it seems that the Toyota tranny is much more likely to fail than the GM unit.

Best Regads,
Shipo

germancarfan1

Citations to statistics please.

shipo

For a change I don't have any. That said, it is fairly well known that both Honda and Toyota have been having their problems with their midsize vehicle V6 transmissions over the last several years, meanwhile, the GM trannies are well respected as being rather bullet-proof. True, they may not be as efficient at transmitting power to the wheels, or shift as smoothly or even have as many gears, they just seem to be more reliable.

Personally I won't drive any of the above automatic gearboxes (I'm a manual transmission bigot) so I have no horse in this race.

Best Regards,
Shipo

captain2

the new TL-S with close to 300hp has a system that detects steering input, if it is not straight, then throttle response is slowed, a system apparently to minimize the effects of TS. Manual trans FWD cars will always be more susceptible to discernable TS problems simply because there are less internal mechanical losses. Your rut corrections would seem to indicate that you are telling me that the FWD cars don't track straight, something I have yet to experience. Under moderate acceleration this would make some sense, however.

shipo

"Your rut corrections would seem to indicate that you are telling me that the FWD cars don't track straight, something I have yet to experience."

No, that's not quite what I was trying to say. Virtually every FWD car that I've ever driven has tracked straight as an arrow on smooth pavement (assuming anything less than high HP acceleration). I have no gripe there.

"Under moderate acceleration this would make some sense, however."

Well, technically climbing an 8% grade is "moderate acceleration". Said another way, if I back off the throttle on the grade, the tracking problem goes away completely. That said, it gets worse when I try to accelerate, almost to the point of being unable to stay in the lane under full acceleration.

Best Regards,
Shipo

imidazol97

There may be two factors involved in the tendency to climb the ruts. I havehad a similar rut on a long hill where the trucks populated the right lane of I70 and a rut developed.

The rear wheels on some cars aren't perfectly parallel and IMHO the preference to slight toe in or out may be to mitigate other characteristics of the car's driving manners.

The rear wheels on RWD don't change their position under higher load since they are not capable of steering. OTOH the front wheels of FWD do have some flex to move under hard load braking or pulling and slightly change the alignment. I had noticed this in relation to slight vibration from road force variation on wheels through the chassis and mentioned to the service manager about more effect from slight acceleration on smooth uphills on a trip vs cruise level or downhill.

I wonder if the flex in front wheels causes the steering you're noticing. Did the cars do the same on flat road beds under acceleration? That would be torque steer (doesn't bother me if it's there in my car). In the ruts that can be the fronts flexing under strong load and can be front rear wheel misalignment. My servce manager was telling about rear wheel alignment changing a person's car who drove the same section of I70 with the ruts; after the careful alignment setting the rear, the car quit fighting on the uphill pull.