Automatic vs Manual Transmission - Explained

What are the differences between an automatic and a manual transmission? I'll explain the difference between cars that have each setup, and how each setup works.
This is a general description of the DIFFERENCES between the two setups. It will not go into detail of planetary gears, or manual gearboxes, but it will give you a general understanding of each, and which transmission has which components.
An understanding of torque converters, clutches, planetary gears, and manual transmissions is beneficial but not necessary to understand the differences.
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[@ArnavJindalAJ]

I just discovered this channel yesterday and man this is freaking awesome. All the car tech its basics explained. Being an automobile enthusiast ive been looking for such a thing since quite a long time. Good Work Bro....Keep that coming.

[@EngineeringExplained]

I would agree that hands-on is a great way of learning. I've spent many days in junkyards tearing things apart to figure out how they work. But these resources are not always available, hence I have videos explaining the basics, so that anyone can learn it.

[@EngineeringExplained]

Sounds like you've built up some hatred for manuals. Have you driven one? Yes, dual clutch transmissions and sequential gearboxes will shift more quickly, but quick shifts isn't exactly what everyone in the world wants. Also, on low end cars, it's hard to find a good gearbox with paddle shifts. Manual transmissions on low end vehicles are great, and a cheaper option. It's not ideal for racing, but for spirited driving it's a lot of fun.

[@EngineeringExplained]

My website FAQs should help answer these questions, check my channel page or the description for a link. Also, you CAN know as much as I know; all you have to do is watch of my videos! That's my knowledge, open and available to all! :)

[@literallyapotato]

Same here. 3rd year into a mechanic apprenticeship and i knew the basics as to how all this happened, but this is explained in such a detailed yet simple way it makes it very easy to learn and remember. Definitely two thumbs up from me :)

[@EngineeringExplained]

@joeslimon Correct; with the use of synchronizers the moving collar can equate the speed of the non-moving forward gear. Many times, reverse has no synchromesh, so the speeds of the rotating collar and the reverse gear need to be equal (typically not moving).

[@kleinj881]

Great videos, appreciate you taking time to make them.

[@EngineeringExplained]

Thanks for watching!

[@austinbeaufeaux1756]

j i totally agreec these videos are great, and help a lot with understanding how many different parts work. thanks man!

[@cboria148]

@@EngineeringExplained if we really don't know too much about how the mechanics work is there a video before this that you recommend watching?

[@EngineeringExplained]

Haven't been quite that fast in my Integra, but close, and that was quite some time ago. I wish you the utmost self control!

[@markbeebe4388]

Manual is fun. I actually paid about $50 extra to have a stickshift instead of automatic when I bought my Saturn back in 2002. Still driving it 11 years later, and it's still a lot of fun to drive. Stick shifters with a clutch pedal are more fun that paddle shifters, in my personal opinion.

[@EngineeringExplained]

It's simply explained in a way that makes it understandable for everyone. I wouldn't say the basics of automotive engineering are "for dummies." There is likely information you could still learn from my videos.

[@EngineeringExplained]

Some people don't like driving. If I didn't like driving I would want it to require as little involvement as possible. That's what auto's do. The require little involvement - just steer and press a pedal. No thought required, it's mindless, perfect if you just want to get somewhere and don't care about the journey. That said, plenty of people who enjoy driving drive automatics, to them I say give it a try, you'll be glad you did. Love my 5 speed.

[@EngineeringExplained]

You have to start somewhere, don't you? If you want a detailed explanation of the stresses and forces involved pick up a text book. I've recommended a few on my website, the link is in the description.

[@EngineeringExplained]

I have a separate video on flywheel's if you'd like to check it out. Yes, it plays an important role with both transmissions, but I was trying to keep the overall video length down.

[@EngineeringExplained]

You simply control a program and tell the computer when to switch gears, it can be done with a traditional automatic gearbox, which is usually the case in cheaper vehicles. Can also be done with CVTs, sequentials, and dual clutch transmissions. I have videos on each if you're interested.

[@EngineeringExplained]

No, you could have dog collars without synchros. The synchros are on the collar to make a smooth transition between a rotating gear and a rotating shaft.

[@ECCvideo78]

Thanks for these lessons about clutch, clutch disc etc.. I've learned a lot ! Thank you very mutch, you are a good teacher !

[@EngineeringExplained]

You're welcome, thanks for watching!

[@AR1G3]

You sir, can be proud! You are an American who prefers manuals, and from what I have heard Americans tend to like automatics more. And secondly you explain all these things that happen under the bonnet so good that I can actually learn from it. So realy realy thanks for that! I see you don't have a video about syncromesh, maybe that's an idea for next week? :)

[@EngineeringExplained]

Yes, you probably have warn synchros. The synchros allow for the gear and the collar to mesh together, but they wear over time. As they wear off, you're basically forcing a collar right into the gear, with no way of matching the speeds, so you simply hear a grinding sound. When you get the RPM close enough, it can still happen, which is what is happening when you rev up to engage the gear.

[@EngineeringExplained]

I appreciate criticism, especially when I've misspoken. And if I had a problem with your comments I'd just delete them or something haha. But when you're going to tell me that I'm explaining this at a 3rd grade level, you can expect me to voice my opinion back.

[@EngineeringExplained]

Sorry you're confused, could you clarify what your question is? I'll try to explain my best.

[@FarmYardGaming]

Always crazy to think someone - or rather many different people - designed all of the components that make up machines that can drive.

[@1Dblade333]

Thanks man. Very happy to talk to someone as cool as you sir. Stay well and have fun!

[@EngineeringExplained]

By direct are you saying 1:1 gear ratio? Depends on what the manufacturer wants to do. Yes, there are 4 speed manuals and 6 speed autos.

[@Bangers_mostly]

please remake this video! maybe with some more visual examples. also, it would really help explaining manual 1st (& how it came to be), THEN explain automatic. Also, it would help clear a lot up if you explain how “manual” mode in automatics differs from an actual manual. LOVE your channel.

[@crosstolerance]

Wow, this was exactly what I wanted to know in great detail. I will be viewing more of your videos in the futurr

[@EngineeringExplained]

Anything and everything can break. Manuals don't have fluid for cooling like the automatics do, and no fluid in the clutch housing if it's a dry clutch. Auto's have fluid for the torque converter and the transmission. I would say manuals tend to seem more robust over time, but in good condition both are pretty reliable.

[@african007stuff]

you are better than many lecturers that teaches these stuff. "Mr. mechanical prodigy"

[@EngineeringExplained]

@thehossman1 Lexus and Chrysler also have 8 speeds now, 6+ seems common now, thankfully. Just need to get them on high torque motors now for a major gain in fuel economy.

[@EngineeringExplained]

Yes, it's quite complex and I had hoped to get around to it eventually.

[@EngineeringExplained]

@villeneuves2 Actually, working with manual transmissions is typically easier than planetary gearboxes, so the cost is generally cheaper. Manual transmission used to last longer, although now a days it's more dependent on the company you're buying from than the transmission you choose. Replacing the clutch is a big cost if you're an aggressive driver, but automatics generally cost about $1000 extra or so initially over a manual.

[@EngineeringExplained]

Power losses through the torque converter. Also, with a manual you can choose when to shift so if you know the most efficient shift points you can get better mpg.

[@EngineeringExplained]

It just means the gears used are straight rather than helical. It's cheaper, but much louder, hence mainly used in racing where noise isn't a concern. If you have a manual car, typically reverse will be a spur gear (google image spur gear and helical to see the difference) and so it will be loud as you back up. Spur gears also don't have an axial load, as opposed to helical gears. Helical gears have greater surface area though, meaning they can deliver more torque, on top of being quieter.

[@DhavalMomaya]

i know this is a car-oriented channel but I'd love for you to do a video on motorcycle transmissions and how they allow for clutchless shifting if one knows how

[@GeneralNOH]

You can do it in cars fine (If you do it properly), especially cars with straight gears (only really seen on track orientated cars). Most truck drivers actually shift without the clutch as they have straight gears, they float the clutch because it doubles as a transmission brake (for matching rpm) The main problem with clutchless shifting on cars is that you have synchro/helical gears, which allow for there to be a mismatch in revs and transmission speed as they engage; they don't engage instantly (there is some slip) which means there is wear as they go from not being engaged to being fully engaged to put it plainly. This means synchros are sacrificial, and you will notice older cars/flogged cars will take more effort to shift or require to be rev-matched because the synchros are going out. Now synchros are fine when you use a clutch as it takes away excessive load which wears the gears, they also make shifting easier and quieter, but without a clutch, they tend to wear excessively as they engage unless you match RPMs. With straight cut gears, they won't actually engage unless the RPMs are matched, or they will engage but create a massive clunk as they forcefully engage and match the revs. Lots of truck drives dont use the clutch for shifting either, as they have straight cut gears. They use it more as a transmission brake Since motorbikes have straight cut gears, you do not NEED the clutch, (Its still a good idea to reduce wear) You can simply let off the throttle (unload) and click it up, similar to a truck driver or someone racing a car with a straight cut gearbox (Dogbox/crashbox tranny). Motorbikes also tend to do this quite easily compared to trucks or cars (which sometimes need encouragement) as the gearbox is smaller and lighter. You will notice if you downshift a bike without a clutch without slowing down, you will hear or feel a bang, this is because the revs arent matched and the gears are forcing them to match; so you still have to take care clutchless shifting a bike especially when going down TL;DR the difference between helical gears and straight cut gears allows safe clutchless shifting on a bike (If done right), combined with the fact that motorbikes have light transmissions with less load which makes it even more seamless.

[@EngineeringExplained]

With modern fuel injection, the injectors can be shut off if you're in gear and not on the gas; so long as your car continues to move, it won't use fuel as the momentum of the car moving is enough to continue rotating the engine. It's not a dumb question; don't feel silly asking, we're all just trying to learn! :)

[@EngineeringExplained]

I've been planning on cranking out a video on how the gear selection process works, it will just take some time. It's fairly complicated to explain, so I'll have to sit down and really think it out so that it's easy to understand. But eventually, I will get around to it. Didn't include much on it in this video, since it's lengthy as is.

[@Cobra4993]

I'm sorry I love your videos but this one in particular sounds like someone was sleeping in your house so you didn't want to talk too loudly and wake them up. lol

[@EngineeringExplained]

This is because many times reverse doesn't have a synchro, so it won't match speeds. Make sure your car is completely stopped when switching to reverse, or it's likely you'll hear some grinding.

[@EngineeringExplained]

The purpose of gears is equal in both styles of transmissions. Autos use lower gears at lower speeds, just like you would with a manual.

[@EngineeringExplained]

Manual, easily, since the driver can choose which gear they would like to be in. That said, there are many types of transmissions. The "best" is difficult to say, but it would definitely allow for selecting the gear the driver would like to be in.

[@Igniter95]

You are a genius dude. I have never met a guy that has known that much about cars. I have been watching all of your videos, and I am extremely impressed. I have learned so much about cars because of you! Keep it up man! Did you ever go to college to learn all of this? Or did you learn it all from experience?

[@EngineeringExplained]

Skyactiv, yes great stuff. I can't say which is ultimately better, but manual is way more fun so that's what I'd go with.

[@EngineeringExplained]

1st and 2nd gear; sometimes useful for example when going down a long decent (mountain road) and you don't want to overheat the brakes.

[@EngineeringExplained]

It's a manual transmission that uses dog engagment. These are basically cogs on a slider (spline) that can engage the gears. It's very similar to what I've explained above.

[@EngineeringExplained]

@tnphysics Automatic gearboxes are simply just more complicated. More precision involved, more pieces that have to be perfect. Fluid pumps, actuators. There's more research that has to go into it. Manual transmissions are far less complex, and can perform the same actions just as well.

[@mickeyhume7600]

Wow, you are better at explaining than all my lecturers. Thanks so much

[@kevynsears7908]

What a blast from the past! Love the channel

[@EngineeringExplained]

Instead of a computer telling the transmission when to shift gears, the driver does, with a signal (pushing a button). It can use the same transmission and hardware that's already in an automatic car. That said, it's getting more common, especially in sports cars, to use a dual clutch transmission with the gear selectors.

[@Ternburn]

not sure how i ended up here... but this guy wins. 8 minutes well spent :)

[@EngineeringExplained]

The younger the better, they'll be even more comfortable with the material when they're older! I've taught a class on internal combustion engines to 11 year olds before, as long as it's interesting to them, it's worth a shot.

[@SimonMbuthia]

Great videos. Just a tip: I think though, that a brief intro of what the part you are about to talk about does would be good, e.g. In this video, we talk about the difference between manual and automatic transmission. *Transmission in a car is what causes the car to... blah blah blah* get the drift? That would make it easy for a layman to understand. I appreciate the effort and time taken to do these videos though :-)

[@EngineeringExplained]

Yep, spur gears are much louder, and reverse is typically a straight cut gear.

[@EngineeringExplained]

Glad you found it!

[@houshidar558]

hey great video really helped me understand how an automatic transmission works or the whole planetary gear system.

[@EngineeringExplained]

That's not necessarily true. There may be more mechanical losses (through friction) in an automatic, so this may be your answer. As far as racing, manuals are used (or selectable gearboxes) so that the driver can choose the optimal gear to be in. Computers can't do that.

[@EngineeringExplained]

Yes, that is a main advantage.

[@EngineeringExplained]

@MK3504 Certainly. In the US it's rare for anyone to drive manual. And in Europe automatics are starting to become more and more prevalent. It's sad indeed, and I think people who drive manuals actually drive better. It requires you to learn how to drive before you can get on a 45+ mph road, unlike automatics.

[@EngineeringExplained]

It would require a video, as I couldn't describe it well with words. It's rather complex, but I do hope to get around to this eventually.

[@ManwaMasterPlan]

I love this channel. If I was you I would make multiple videos explaining how to drive a manual transmission and tips for noobs. Every year thousands of people learn how to drive a manual and go to youtube for information on the subject, could lead to you getting a lot of views. I am looking for information on "lugging" an engine and shifting smoothly

[@EngineeringExplained]

If the engine speed and the transmission speed (which results from the speed of the tires) is the same, then you can shift without using the clutch, because your connecting two things that (relative to eachother) are not moving. Obviously they are moving, but moving together. So if you know at 60 mph your engine is at 2500 rpm in 5th gear, you can rev your engine to 2500 rpm (while going 60) and put it in gear without a clutch. Good practice? Not really, youll grind your gear collars eventually.

[@EngineeringExplained]

@ajpanton Put simply, it would not work well. Automatic transmissions have multiple clutches and bands which could not be operated by a single foot like a simple single clutch manual transmission. I suppose it may be possible to put a tradition manual trans. in an automatic, but it would be rather complicated. A torque converter is a clever replacement to a clutch, and automating a clutch, plus 3 or more selector arms to switch gears would be a challenge.

[@EngineeringExplained]

Glad you like the videos! Search my channel for "Transfer case" I've got a video on it, cheers!

[@EngineeringExplained]

It's the third pedal, the one all the way on the left, in a manual transmission car.

[@EngineeringExplained]

Shouldn't cause any problems, no. Transmissions should be designed this way specifically for emergency purposes as well. If you can't stop accelerating, just pop it in neutral and use the brakes.

[@EngineeringExplained]

Well, for example, you can't simply crawl in traffic with a manual (without slipping the clutch) like you can with an auto, so the first gear may be a bit higher gear ratio. They may also place the gears closer together, since manuals tend to be for more enthusiastic drivers.

[@alexandrak.2391]

Yay now I know why the car makes these weird grinding sounds whenever you change speed. Thanks!:)

[@EngineeringExplained]

Glad to help!

[@rgeghetyhruheuyu5682]

well said. a survey in western europe prooved that driving with manual trans increases the risk of accidents in comparaison with auto transm

[@jesusmartinez9459]

Great explanation of the automatic with the planets

[@EngineeringExplained]

If there is less friction, then yes. But also the GTR is AWD so it will likely have more losses than most 2WD vehicles.

[@JasonGafar]

Hey man, just wanted to extend my thanks for this video. And I thought I was a loser or 'nerd' for having an erasable board in my study room. Best of luck with all your endeavors within engineering.

[@2151abell]

You said it.... Manuals are JUST FUN TO DRIVE ! Amen... Love your vids man... you do a great job with simple explanations. How about a vid on Transfer cases in 4X4s... just throwing that out there ! THANKS !

[@kupaksulja]

Thanks a lot man. I'm learning to drive a manual and I agree its more fun than an auto I would imagine. However i never seem to get the concept of how it works and this helped a bit.

[@EngineeringExplained]

Interesting question, perhaps so. Or it disconnects at low enough speeds.

[@LordHyren]

You can tie into your AT wiring in your car and use a switch to force lock your converter clutch. This will help your AT mpg a good bit, your transmission will do it much slower than necessary, especially under load.

[@LordHyren]

The clutches in the transmission are control by a pressure valve unit and a pump on the input of the transmission. As the input speed of the transmission increases so does the pressure of the pump. When the pressure reaches a 'shift point' it forces a valve open and follows a channel to the next clutch you are dis/en-gaging. This channel changes depending on the position of all other clutches. And sometimes multiple clutches change positions in a given shift.

[@EngineeringExplained]

Yeah, what I'm saying is it more than likely works like an automatic, using a torque converter still rather than a clutch for the "manual" shifting.

[@EngineeringExplained]

Thanks Kenny!

[@EngineeringExplained]

@modelearth Personally when I've been over there I've seen mostly manuals, but people I've spoken with abroad say autos are becoming more popular.

[@ultimatevideowatcher]

That is true, I never said dual clutch gearboxes had torque converters. Most racing transmissions are electronically controlled you are correct.

[@EngineeringExplained]

Interesting. In my experience it seems automatics drop dramatically in RPM when going downhill, thus entering some form of "neutral." When you step back on the gas, the RPM has to rise a certain amount before you begin to accelerate. So it would seem there is no purpose to shift into neutral regardless of the situation (for the purposes of saving fuel).

[@EngineeringExplained]

Yes, clutches are still used in automatics.

[@jazzy2928]

Extremely thorough explanation! Easily understood. Thanks!

[@oldfashionedwrx3574]

Ok thanks, I heard something like that and what you said actually confirms it. I agree with you.

[@EngineeringExplained]

@skaterman1q2 I wish I could say class, but mostly just reading on my own. Books, the internet, magazines. Anything car related I probably read.

[@Islander39er]

yeah thanks man, i wonder if i need to see it actually in front of me in super slow to understand. it's the one major thing about vehicles I cant seem to fully get like i said. and i'd really like to. thanks.

[@EngineeringExplained]

Yep, same idea and purpose though.

[@1Dblade333]

Thanks for the response man, I love your videos! I myself got addicted to driving fast in mom's Toyota Matrix (haha) and bought myself a 99 civic si for college where that habit only worsened. 135-140's the fastest I've ever driven (how fast have you been?) and after 130 it's honestly begging for death at even the slightest mistake. I've since then found an amazing partner and decided to slow it down, but I'm going to invest in a bike and ride safely! Wish me luck and much self control!

[@pratyushbhattacharya9527]

it would be great if u make a video on automatic trans alone..... u r a great teacher... thnx fr teaching us!!!

[@jonesmat]

I'm very unsure of my future as far as education goes, but I admire your knowledge and ability to explain the workings of cars, as well as your voice, as a result I'm kinda leaning towards a mechanical engineering degree now, but what exactly does mechanical engineering cover? Also did you learn more about cars from college or by yourself?

[@EngineeringExplained]

Thank you, kind one!

[@MrTruth111]

I agree with Engeneering explained, perhaps it has to do with shifting style. Use low throttle in first and only give gas when completely locked. And some transmissions need regular fluid replacements, also depending on usage. I always drive Volvo's and an original clutch will last 200.000 km easily, some people even manage to drive 300.000 with one!

[@EngineeringExplained]

Many electric vehicles are geared directly to the tires, the transmission is a single speed, so manual wouldn't really exist. Torque converters aren't needed because electric motors don't stall like IC engines.

[@EngineeringExplained]

If you're talking about about the "manumatic' type transmissions, it's more like an auto except you flick a paddle and a computer does the work of changing the gear.

[@mohammedbinopata9977]

Question for ya Jason, first of all huge fan! I'm studying Mechanical Engineering at Auckland Uni, you are about ten times more efficient and a hundred times more interesting than our lecturers ya legend. Back to the question, lets say the car has been put into neutral, the clutch has been disengaged and in a previous video you said that the disc is spinning freely Now if the output shaft is spinning at the speed of the wheels, how does the car match the revolutions of the outer shaft to that of the input & countershaft when a gear is selected? And is it because of that difference in speeds between shafts that you cant go directly from second to fourth gear say, if your not at a high enough speed?

[@hmm2928]

see his video on clutch plates. u will understand.

[@EngineeringExplained]

Yes; see next comment.

[@EngineeringExplained]

Thanks!

[@Freshbott2]

Awesome, your videos are the best out there by the way.

[@EngineeringExplained]

Bad transmissions, there's a system of clutches and belts in there; could be electrical as well. Have it checked out.

[@RedWrongDog9]

Can you do a video or just quickly explain how exactly automatic transmission switches gears? Like the physical motions of all the clutches and inner parts that get you from 1st to 2nd etc. and how that occurs? Thanks

[@EngineeringExplained]

Yes, the autos typically have a better rating, but real world it's possible to do better with the manual. The average driver may see no difference.