Not sure if it’s the same but… AWD is a system that’s always running where as 4WD is a setting you can change to. They aren’t the same thing
Comment on Tourists write-off uninsured rental BMW 4WD in river crossing gone horribly wrong in Iceland
PP_BOY_@lemmy.world 11 months ago
It’s always been interesting to me how what we (in America) call AWD is called 4WD in Europe
TheMightyCanuck@sh.itjust.works 11 months ago
Ilovethebomb@lemm.ee 11 months ago
No, it isn’t. The Toyota Land Cruiser and Land Rover Defender series of vehicles are permanent four wheel drive, and are advertised as four wheel drive.
PP_BOY_@lemmy.world 11 months ago
I know they’re not the same thing. But (from my limited experience with European car discussion), 4WD is used to refer to both AWD And what we’d call in America as “real” 4WD. Watch any old Top Gear episode with a Subaru to see what I mean. Or, just watch the video. The BMW X-series is marketed as AWD in the US, but the OP title and YouTube video both call it 4WD.
Bonehead@kbin.social 11 months ago
Not quite. AWD has a transfer case with an open differential, so that the back wheel and the front wheels can turn a different speeds. Some vehicles can actually switch between RWD and AWD.
4x4 has a transfer case with a locked differential, so that you get more traction. But this should only be used on loose surfaces because on solid roads you can damage the transfer case leaving it in 4x4. Some vehicles have a "part-time" 4x4 that switches the transfer case to unlock the differential, giving you AWD that won't damage the transfer case.
Ottomateeverything@lemmy.world 11 months ago
It’s not. They mean different things, and the terms are not really all that standard since there are many different types and everyone does things a bit differently.
In general, AWD is generally always on, 4WD often has other modes too (like 4 low, etc)… But the mechanics of how they’re setup and how they actually go about distributing power are very different and complicated whereas even when running, they aren’t really doing the same thing.
niktemadur@lemmy.world 11 months ago
I thought 4WD meant that you drive with either two wheels or four doing the traction, and it’s a setting you turn on and off manually, while AWD turns each of the four wheels independently, which also allows for just one or three wheels turning, and it’s an automatic process.
Ottomateeverything@lemmy.world 11 months ago
Not… Really. It’s actually much more complicated but we’d need to compare specific vehicles to explain the differences really.
4WD does tend to have on/off and different modes while AWD usually doesn’t, so that part is kind of true?
But AWD doesn’t drive “every wheel independently”. They do usually try to turn all 4 wheels, but then a set of diffs and clutches will essentially “disconnect” the wheels that aren’t gripping, but it’s not like it’s literally independently driving each wheel…but I guess you could say it’s individually disconnecting each wheel? But that’s not really the same.
But yeah… It’s… Complicated.