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America’s Cars Are Getting Faster and More Efficient

bloomberg.com

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Re: America’s Cars Are Getting Faster and More Efficient

#521

Post by alistairSH »

darksim905 wrote: post #504
alistairSH wrote: post #395

Earlier quoted context omitted.

3,000 mile oil changes hasn't been a standard recommendation in the US for at least a decade, probably longer. These days, most (all?) cars have an idiot light that pops on every 5-10k miles, based on usage patterns. Some have a more robust algorithm than others. Either way, in my experience, my last 3-4 cars (Jeep, Lexus, Volvo, VW) have all gone about 8k miles between services, as indicated by the light.

The 'idiot light' is not based on miles, but on how much oil is actually in the engine. There's a sensor in there that if it touches air, essentially, the light goes on. You can trip this on certain VWs if you turn very sharply & you are low enough on oil. Compare this to GM/Chevy vehicles where this is a 'solved problem' with their on board DICT computer, it measurements the containment (via resistance? electricity?…

The 'idiot light' is not based on miles, but on how much oil is actually in the engine. There's a sensor in there that if it touches air, essentially, the light goes on. You can trip this on certain VWs if you turn very sharply & you are low enough on oil.

I'm talking about the "Service Required" indicator/message that appears in the central info display, not the "Check Engine Light". Two different things in the VW, Lexus, and Jeeps I've owned.

Re: America’s Cars Are Getting Faster and More Efficient

#522

Post by vlucas »

cglace wrote: post #43
vlucas wrote: post #17

I have a 2016 Ford Mustang GT/CS and consistently get 23-24 MPG with mostly highway/freeway driving. It's unreal that a 5.0L V8 with 435HP (stock) gets that good gas mileage. The materials and fit & finish is better all around too. We are truly living in the middle of another "golden age" of automobiles. Watch out though - here come the EVs :)

Now if they could just work on making those cars quieter. So they don't deafen me when I'm trying to enjoy a nice day with the windows down.

Actually, the stock setup on the 2015-2017 models is pretty tame/quiet. Most of the super loud cars are after market exhaust/mufflers.

Re: America’s Cars Are Getting Faster and More Efficient

#523

Post by vlucas »

onion2k wrote: post #332
vlucas wrote: post #17

I have a 2016 Ford Mustang GT/CS and consistently get 23-24 MPG with mostly highway/freeway driving. It's unreal that a 5.0L V8 with 435HP (stock) gets that good gas mileage. The materials and fit & finish is better all around too. We are truly living in the middle of another "golden age" of automobiles. Watch out though - here come the EVs :)

24 MPG is embarrassingly bad. A 1970s Datsun 240Z gets the same fuel economy. Compared to a modern luxury car, a new BMW 3 Series will get 80 MPG on a freeway. There's nothing wrong with buying a gorgeous car like yours, there are plenty of reasons to have one, but trying to claim it's environmentally friendly is just ridiculous.

Whoa there. I never said it was "environmentally friendly". That is indeed ridiculous. Just saying that for the amount of power it has, it gets better than expected gas mileage.

Also, it looks like a 1970s Datsun 240Z averages significantly worse: http://www.fuelly.com/car/datsun/240z/1973 - further proving my point, and the one of the article in question.

Re: America’s Cars Are Getting Faster and More Efficient

#524

Post by MertsA »

darksim905 wrote: post #503
MertsA wrote: post #456

Earlier quoted context omitted.

To be fair, I didn't know that the coolant in a Bolt is supposed to be good for 150,000 miles, that's a good bit longer than I figured. I was thinking closer to 90,000 miles, but you're right, the lower service temperature and also less metal surface area will make it last longer in an EV. But in an ICE, exhaust and oil should not be getting into the coolant at all. If it is, any long life coolant is going to need to…

I think you're confusing service interval items that are "check/verify" with "need to do". I'm almost positive you don't need to check or change anything that extensively on a manual transmission VW. Also, we figured out a long time ago that sealed transmissions are okay, but it all boils down to how you drive the vehicle. Yeah, if you treat the car like shit, or you get the transmission checked (if this is even poss…

No the 40,000 miles really is for replacement. That being said it does sound pretty low and it is for their fancy dual clutch direct shift transmission. But sealed transmissions with "lifetime" fluid wear out faster than a decent transmission. There isn't some major transmission improvement that allows for a sealed transmission, it's just a regular transmission that you can't perform maintenance on.

As for whether or not it's strictly necessary, you can avoid oil changes altogether and a decent car will make it quite a long way before it seizes up.

https://www.reddit.com/r/Justrolledintotheshop/comments/2zoc...

You can do the same with a transmission or a differential, but they'll last a lot longer if you replace the contaminated and worn out fluid with new fluid.

But even just checking the fluid level in a transmission or differential, if the fluid is low, you can't ever just refill it. It didn't burn up, you've got a leak and it'll probably just get worse if you ignore it. There are plenty of vehicles out there with absolutely ludicrous mileage on them, on a modern vehicle, if you keep on top of maintenance, engines and transmissions can last hundreds of thousands of miles.

As for suspension components on a Tesla though, I would expect to spend a decent bit keeping all of them in working order. The suspension on a Tesla is really nice, but air suspension isn't nearly as robust as a simpler Macpherson strut setup on an econobox. It's fancy, but fancy suspension and more moving parts means more things to wear out and fail. You've got 2x the ball joints to fail in the front, additional linkages all over, and more bushings to wear out.

Re: America’s Cars Are Getting Faster and More Efficient

#525

Post by irixusr »

systemtest wrote: post #370
irixusr wrote: post #69

Earlier quoted context omitted.

Having lived (and appreciated) Europe and their cars: 1. You guy drive a lot less than us. I do trips three times as long as what would destroy me in Europe (twice a month I drive 500 km without stopping and back the next day) 2. Are you using the imperial gallon or the american gallon? Very common mistake (the mile used in the article looks like and probably is the 3.8l gal) Edit, you're using the right gallon.

Driving 500 kilometers without stopping is terribly dangerous for yourself and the people around you. Please be considerate.

No, it isn't. It's the difference between driving in the EU and driving in N America.

I can't think of any 500 km route in Europe that wouldn't destroy me. And a little engine screaming for dear life wouldn't help

Re: America’s Cars Are Getting Faster and More Efficient

#526

Post by dragontamer »

darksim905 wrote: post #506
dragontamer wrote: post #448

Earlier quoted context omitted.

I disagree. As eeks points out, fully automatic transmissions are kind of awful at making decisions. I have a case when I was driving into work this morning. I got stuck behind a funeral procession going 35 MPH on a 65 MPH interstate highway (Uggghhhhh) I look to my left-mirror, and I see a spot I can feasibly make, I just gotta time it right to get "into" the flow of traffic. So what do I do? I drop to 2nd gear (The…

Automatic transmissions are better & smarter than you. you may have to drive a little differently if you're driving an automatic in the scenario you described, but saying that it doesn't ''know'' what you wanted to do means either your transmission is virgin & hasn't learned your habits, or, had a different driver for several years & is shifting at the wrong points. This 'ready to go' thing is all hogwash manual elit…

Look, a CVT semi-automatic probably would outperform me. I'm no master driver or whatever.

But a typical automatic transmission? Dude, I have a huge advantage as a human. I have eyes. I can see things the engine cannot.

It takes time for a internal combustion engine to rev up to its ideal torque band. The Ford Focus is a turbocharged engine, which means it only achieves maximum torque above 4000 RPM.

Since most automatic transmissions are tuned for fuel efficiency (ie: 2000RPM band or so), they will perform worse when you're trying to accelerate. The manual driver has the advantage that they can choose fuel efficiency (ie: 2000RPM most of the time), or in cases of emergency... kick it into (low) gear for very high RPM to maximize the torque band.

-------------

ICE Engines are all about tradeoffs, and the manual driver can choose the RPM-band that best matches the situation.

Would a properly tuned automatic beat me in fuel economy? Probably.

Would a properly tuned automatic beat me in acceleration? Probably.

But no automtaic can be tuned to do both at the same time. Since high-Torque is high-RPM only... and fuel efficiency is low-RPM only... the computer cannot be tuned to try to do both at the same time.

Re: America’s Cars Are Getting Faster and More Efficient

#527

Post by ljf »

derefr wrote: post #484
ljf wrote: post #348

Earlier quoted context omitted.

I'd be interested to see that. While yes people falling from a horse might be in trouble - generally horse will try to avoid danger themselves - and there would have been only so fast that you could ride a horse in a city, due to the roads available for this.

Generally, "cities" were much smaller (and fewer) then; not large enough to have much need to ride "through" one. Most horse-riding (though not carriaging) would involve using a horse to travel between the various towns in an area, via not-necessarily-well-kept roads. Some non-negligible percentage of horse-riding was also done by the nobility, where the horses were used either for hunting, or for military campaignin…

Horses in London 1903: https://www.youtube.com/watch?v=v-5Ts_i164c

Re: America’s Cars Are Getting Faster and More Efficient

#528

Post by insta724 »

creepydata wrote: post #468
ghaff wrote: post #155

Earlier quoted context omitted.

>People are going to be on their phone at 70 MPH no matter what do-dads are in their car Somewhat disagree. It's not a distraction panacea (based on various studies) but if we had voice recognition and natural language processing in cars that really worked well, there would be a whole lot less temptation to look down at a screen or type. Not justifying people who do so. Just observing that better tech would largely e…

Well I was alive before cell phones and I'll tell you people will find plenty of reason to not pay attention at 70MPH.

The MPG chart is of median MPG among production vehicles, not mean, and not mean weighted by person-miles driven.

https://insta724.com/

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