sorry for bad alt text, I lack the terminology to describe this accurately
(i'm not a mechanic, i have no earthly idea if this is accurate. Don't sue me)
What's going on with the caster picture? Not sure what it is showing.
this post was submitted on 18 Mar 2025
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Most regular cars won't have an adjustment and are factory set, but you get into sports cars and after market stuff you can change it.
What it does is controll how hard the car/steering wheel want to point themselves back straight ahead(and a couple other things, but thats the main/most obvious one). All these drawings are way overdramatized to make it easy to see differences in everything that is being talked about. Just a few degrees in caster angle can make a huge difference in how hard it is to turn the steering wheel and how quickly the car will straighten itself if you just let go of the steering wheel.
Pretty much every vehicle you buy now will have a caster angle a bit on the positive side. That way the vehicle always tries to go straight and stable unless you want to turn the wheel. It makes it "more work" to turn, but thanks to power steering that's not really an issue.
A negative caster would be very unstable feeling and pretty much useless to have on a vehicle.
As far as telling from the picture what caster is, it's sort of a bad image for showing it. It would have been more intuitive to picture where the strut was mounted to the car body in relation to where the middle of the wheel is. A positive caster will have a strut angled like ( / )--------( l ) if the car was facing to the left.
it has to do with the angle between the point the tire pivots (steers) on and the point the wheel spins on. The steering point needs to be forward of the spinning point to help the car go straight down the road. Think of a shopping carts front wheels (they're called casters), and how they'll pivot around with the direction you're pushing the cart. That angle can be adjusted so the car tracks properly...
It's showing the 'knuckle' the wheel is mounted to leaning forward and backward.
Alt text is there to provide all alternative for the visually impaired. A good rule is that it should provide as good of an experience as anyone else would get. Given how complex this image is, a separate text write-up would be more useful, so don't sweat it.
I remember one time I changed my struts, rotors, pads, and mounted new tires myself. When I was done, I had to drive it about 30 miles to get it aligned. During the drive to the shop, its alignment was "all of the above" in the graphic 😆
0/10 do not recommend.
If you do work like this at home you can often get the alignment close enough for the drive to the alignment shop by taking precise measurements before disassembly, paying attention to the amount of turns on end joints etc..
The best option is still to trailer it to an alignment shop, ofc.
If you're really careful you can do the whole thing yourself with some string and a yardstick and hand tools. Especially when a lot of cheap cars will only have an adjustable toe angle and only the front of the car.
In my defense, I was going to take it to the shop down the road (~3 miles) but they were backed up for a week.
That's a good defense :)
What's with those cars that camber their tires all crazy on purpose? Style or is there a functional reason?
Crazy negative camber is just a style thing. You can see fairly aggressive/negative camber on racing cars, and on a track it serves a purpose, but even in those cases it usually much milder than what I think you're referring to .
Standard street performance is around 1-2 deg negative camber, an experienced eye can tell when looking at the car from the outside but it's not super obvious. Aggressive track camber is around 3-4 deg, that's getting a bit more obvious to the naked eye, but still looks fairly normal. The cars you're talking about with like 10+ deg of camber, where the outside of the tire isn't even touching the pavement, is just the owners making their car handle like shit and burn through tires every 1000 miles because they think it looks cool.
Is there any reason other than appearance to have your wheels negatively cambered? I see it pretty frequently these days and it just looks stupid and wears out your tires in weird ways.
In certain driving conditions it can improve cornering, but for most cases, oem recommended angles are best. Extreme negative camber is purely cosmetic and wears out your tires in weird ways.
unaligned
misaligned
the over and under-inflation wear isn't as much of an issue these days as it used to be. In the old days of bias-ply tires, that was definitely the case. You could have a low tire and hardly be able to tell, because the stiff sidewalls would hardly sag. Their flex point was down the middle of the tread. Radial tire construction puts the flex point in the sidewalls, which doesn't distort the tread as much, plus gives a much smoother ride...
I wouldn't worry too much about the alt text anyways. Alt text is mostly meant for blind people, and last I checked, blind people don't drive or work on vehicles.
Chat, is this ableist?
The DMV I used to go to had a vending machine that said profits went towards supporting an all blind baseball team. I’m still not sure if it was legitimate: I get that “blind” could mean with 20/400 vision, which isn’t that difficult to correct well enough to play baseball, but that seems like one of the worst sports to play with limited visual input.
Every time I saw it, I had this thought process, then scolded myself for limiting people, then thought about how dangerous a fastball can be, then scolded myself again. I haven’t thought about that in a decade at least.
Also, you really don't want to play baseball (or hardly any other ball sports) with such bad vision, even if glasses offer awesome correction.
The refraction difference between the front facing direction versus sight out of the corner of your eye outside of the lens range is rather extreme and causes significant shear and even double vision of sorts when looking near the edges of the glasses.
Imagine seeing a baseball coming your way out of the corner of your vision, and you see a ball both inside the corrective lenses, and also see a ball offset outside of the range of the lenses. Depth perception goes right out the window, and you can almost be guaranteed to get smacked in the head with the ball.
No, to be declared legally blind, your vision has to be so bad that even with the best correction, you're still 20/400 or worse.
I should know, I'm around 20/500 without my glasses, but close to 20/20 with proper glasses. Therefore I cannot be declared legally blind.
Hey, just stating the obvious, the diagram wouldn't be very useful for a blind person anyways.
Besides, how would you write out alt text that clearly explains the diagram for blind people?
If you can think up a good explanation that makes sense, feel free to offer OP some suggestions...
I looked it up because I was curious and there are atleast two blind mechanics. Can't speak as to how effective alt text would be in teaching most blind people though, I imagine it'd be way easier to learn hands-on
Fair enough, there's almost always exceptions to the norm. Still, I don't think it's even possible for a blind mechanic to feel his way to fix alignment issues.
Me, I have Multiproblem.
Time before ABS: local wear
Lol if this is that I think it is, I've always just called it a "flat spot"