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Comment by neogodless | Hacker News Reader

Wait until you find out how many gas and diesel powered trucks are RWD!

At least in the U.S. below a certain ~longitude~ latitude it's quite common.

Autotrader says there are 246,000 used trucks for sale nationwide with AWD/4WD and 38,000 with rear wheel drive. For new it’s 429,000 AWD/4WD vs 51,000 for rear wheel.

Volume wise it’s of course Texas with Wyoming, Montana, and North Dakota having the largest ownership share.

The majority in that statistic are selectable 4WD, which isn't the same as AWD. Pushing the two groups together skews the numbers a bit. Most trucks since the 1970s have been 4WD, ever since companies like Muncie and Borg-Warner started selling axles to Ford and their cohorts. AWD trucks are a relatively new phenomenon, with the first one I can think of being the limited production GMC Syclone in 1989, and it being a truck was an emissions loophole. I think the 2005 Honda Ridgeline was the first real mass produced AWD truck, or perhaps the Subaru Baja from 2003 if you consider that a truck rather than an open deck car. Right now I think only the Ridgeline, Hyundai Santa Cruz, and Ford Maverick are sold as AWD, whereas every other truck is selectable 4WD.

Push the goal posts of you want. OP specifically said rear wheel drive.

There’s a whole community that doesn’t consider anything without front and rear lockers, dana 44 axels, frame on body, and 37s with bead lock a real off road rig.

There is a difference between AWD and 4WD, because 4WD trucks are RWD until you manually change the mode. AWD is all on all the time and is FWD biased, usually something like 70:30 F:R. For most of their lives, even when towing, 4WD trucks are used as RWD only. As for specialized off-road vehicles that wasn't what we were talking about, but yes those people split hairs down to the micron for what constitutes what.

There are so many varieties of AWD. Most are wet-clutched (inside or outside of the main transmission), some are lockable or torsen center differentials, Prius adds electric power to the rear wheels to complement the FWD hybrid setup. Traditional 4WD with a transfer case using a manual shifter-actuated gear selector isn't very common any more. My 1999 Suburban had a wet clutch in a standard truck-shaped transfer case, one side of the front differential had a solenoid to lock/unlock one wheel to the side gear to keep the front drive shaft from spinning in RWD mode, and used a motor to mechanically engage or disengage the wet clutch (between the front and rear outputs) and to slide the engagement ring to offer AWD (rear-wheel biased, engaged when front and rear wheel speeds differed anywhere from 0 to 100% torque transfer) or 4WD (clutch fully engaged), and even 4WD-LOW by running the motor the other direction to engage the planetary gearing with the rear drive shaft.

In my mind, the biggest difference is whether front and rear drive shafts turn at exactly the same rate; if so it's "4WD". If clutch slippage or a differential allows different front and rear axle speeds then it's some form of AWD. But many AWD systems have clutches capable of effectively locking the front and rear driveshafts. E.g. the Suburban had tire-hop turning on pavement in 4WD mode which is about the most torque that drive-train would be expected to encounter.

    > neogodless: <snip> At least in the U.S. below a certain longitude is quite common.

Latitude.

I KNEW I was going to get that wrong.

The mnemonic i use is latitude is flat.

I was going to ask if you were making a joke or just too tired to spell mnemonic correctly, but they would've been pneumatic, not pneumonic.

Edit: oh, boo, you fixed it.

Hadn’t had the morning coffee yet.

I usually say to myself "ladder" and that helps. But this time I slipped. Rough morning. Wheels fell off on the way to work.

latitude -> flatitude

I hate to admit it, but the Corona "Change your Latitude" ads are what locked it in for me.

As they say, if it works it’s not stupid.

Ha! Mine is the Jimmy Buffett song.

I say longitude goes longways, which I know isn't accurate except fairly close to the poles, but I remembered it like that when I was a kid and it stuck.

Latitude is the only one that matters between the two.

Longitude is also twice as long - 360 vs 180 degrees

It's counterintuitive because the prefix refers to the lines, but we're usually describing points along the lines. We know intuitively that "lateral" is side to side, and "long/length" we would expect to be vertical, but that describes where the lines sit, and the measurements are perpendicular to where the lines sit: you choose a horizontal line to describe a height(/length), and a vertical one to describe width.

So just remember that it's opposite to intuition, which will work until you've gotten comfortable enough that your intuition is correct and will then guide you exactly opposite.

I use Jimmy Buffet’s song “Changes in Latitude, Changes in Attitude”, meaning head south to Key West to change your attitude. Ergo, latitude is north/south.

EDIT: ninja’ed https://news.ycombinator.com/item?id=48065792

Easier mnemonic:

Lots of wines advertise their latitude of origin

Longitudes are meaningless for wines

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