Grinding Gearshift Explained 

My life makes sense now.

I just got done with a transmission class and I still didn't understand how the synchros exactly engaged gears and where the 'grinding' sound comes from if the gearsets are always in mesh already. My teacher failed to explain this, but you did it perfectly well. Just wanted to thank you. Great video, perfect length too.

It's refreshing to see a video this clear in what's actually happening. Thank you for explaining

Thanks to the engineer and camera person for a real life demonstration and commentary of what happens during a grinding gearshift.

Done two years in college studying motor vehicle, and one of my main assessors failed to explain why sometimes the gears screech or find it hard to connect, but your explanation was Brilliant, thanks for sharing this video buddy.

This channel really grinds my gears

Thank you Dave! After all these years this video is the one that makes sense with almost all types of cars, not just our favorite old Mini Coopers! I always try and explain things in a way that does not require the viewer to be a professional mechanic!

This has to be the best video for describing the function of a syncromesh, and I've seen a few. Top video mate.

Super thanks for your video. This is the best video about how behave a syncro worn out

This is the best video on RU-vid for an explanation on how transmission gears and synchro rings function... Thank you

Best explanation of how synchro rings work. I've watched others tell what they do, but explanation was lacking. Great job.

Uncle had better video quality 10 years ago than most instruction videos today. Also uncle is still doing youtube and he doesnt look a day older mashallah, may Allah give him more and everybody leave a sub!

I have a 2002, 3000 Mule I purchased a week ago. High gear grinds so I lowered the idle thinking that was the problem. Although lower idle made a less severe grinding. Now I know the problem. Thank you for your passion explaining synchronization of gear shift. Now it's my move...Thank you my friend...

Great Job explaining the synchronizers. I did understand the concept but didn't know you could see a gap between the cone and gear, always interested in learning more. Thanks!

I didn't even need this video but you did such an excellent job that I all of a sudden wanted to know. I now understand something I wasn't looking to learn only because you were so very brilliant in the simplicity of your explanation. Your camera lady was equally BRILLIANT with her steady hands and angles so what you were saying was easy to see visually. Well done!!

Very very very nice video, layman terms well explained, thank you

Absolutely brilliant. You genuinely taught me something today. THANK YOU. So is this where/why double de-clutching to match the gear speeds stops the crunching??

best and fastest explanation of synchromesh I've seen on here. awesome vid

Great job explaining how the gears work to provide for a smooth shift. I won't be able to perform the work on my car but at least I have a better understanding of what I'm up against. Terrific

Best video I've seen on syncro wear and gear grind. Thanks!

This finally made me understand exactly how the synchro ring do their thing.

very good explanation and for the first time i actually get why my car's 5th gear grinds like it does. now just to try and get it repaired..

This video really helped me out last night my bike was making that same noise in third gear

I just got a manual car, have absolutely no experience driving them but my entire family does XD. My dads wife ended up grinding her gears and it broke the car so I'm trying to learn everything I can before someone teaches me how to drive it. This video was very simple and easy to follow on what's going on with the car. Thank you!

Thank you! Short, sweet and to the point! I see alot of videos who drag off into never never land with info that even for a new shade tree mechanic its a waste of time! =]

Great explanation for why my 1958 MGA gears grind when down shifting from 3rd to 2nd gear except when I am at 15MPH or less.

Thank you! That was a most elegantly simplified pathway through complexity. I truly appreciate your presupposition of our common-sense. You set me at - ease within moments of your opening. Me thinks it makes an already articulate explanation much easier to grasp, by perhaps the widest range of viewers possible.

My B5 Audi has a 2nd gear crunch in cold weather, I have alreay read about the synhros and understood the problem, but never found and explanation what mechanical process actually happens. Thanks mate! :)

Grinding gear changes equals worn out synchros usually. Life makes sense now! Thx

That was a nice explanation. Very easy to understand and helps me know what to look for when I go to rebuild my transmission soon. Thank you.

Now i understand why you have to pull your leg off of the clutch slowly. the clutch part is to make it so it got up to speed slowly while applying gas to it all. it makes sense now. thanks for the tip.

Man what a great explanation! Thank you so much!

This is just an awesome explanation of how syncros work. Thank you!

thank you very much for breaking this down to my level lol

What a great expxlanation and demonstration. I never understood it but but this make perfect sense, thank you sir.

I feel like I just got smarter after watching this video. Thanks !:

That's the best explanation I've ever seen on how a synchromesh works ;)

straight to the point I love it.. great video. if someone can't understand that they shouldn't be watching any car videos lol

Thank you for this video. Now I know what is wrong with the transmission. I know a lot about cars, not tansmissions. You do a fantastic job of showing, and demonstrating, the problem. Easy to watch for a person with intelligence. And, it's a problem I don't have the ability to fix. However, I won't sound stupid when I take it in. Thank you for this vdeo.

You have explained this very well. There are youtubers with 500x your subscribers that dont explain it as well.

I'm watching this because I've just done it in my car and I feel guilty .... Very well explained 👍

An excellent explanation and demonstration. Thanks mate !. It would have been a real saviour back in the early 1980s when every old clunker I owned had roached synchro cones. I probably would have had a crack at replacing the cones and bearings rather than buying similarly used gearboxes and installing them myself.

This is the best video on RU-vid. My 2011 has this problem on my manual transmission. Wtf

I take my hat off to you. Fantastically explained as to why my Mini gearbox crunches. But why does this seem to happen so much with Mini gearboxes between 2nd/3rd?

Nice. Simple and easy to understand. Thank you sir.

Great Demonstration!

Great demonstration with a clear explanation. Fantastic job and thank you.

Perfect explanation! that hand held gear explanation was perfect. Thanks!!

well explained and talked through properly thanks, my vans gearbox is needing the synchro fixed now I know what they will be doing thanks

Good job explaining, I've changed my clutch 3 times already, because my fth gear is grinding.

great video. jumped straight to the point and was perfectly clear.

Great video and I noticed you have an Optonica RT7070 cassette deck too ! They were great back in the day !

Wasn’t expecting new age Mr.Bean.

3rd gear always grinded, would just double clutch to avoid it. New rings did the trick, thanks.

Automatic transmissions work quite different, using constant hydraulic pressure. It's unusual to hear grinding, because they will usually fail before that, and you just get all neutral. I'm not an auto trans expert, but it should be easy to find info on your issue. Try some of the Mustang forums. Most transmissions can be rebuilt, although sometimes, a "factory replacement" can be cheaper!

Most people do not understand why 2nd gear synchros get destroyed so often. The reason is simple. Transmission designers at their drawing board reason that you have enough torque to have a big jump (wide ratio) into 2nd gear. That is correct, BUT what they don't realize is that nobody wants to wait and rev match that shift, so they just jamb it into 2nd gear and wear out the syncros in 2nd. Unfortunately most designers are not manual enthusiasts, and so this is a common design error in many manual transmission cars. My transmission never grinds even when the car is old, because I always rev match, and wait for it in all gears. Progessive wide ratio 1st to 2nd gear transmissions keep the shops busy and maybe that is the name of the game. How can we convince them to make all modern 6 speed transmissions close ratio all the way up?

finally someone that knows what hes talking about

Well that answers my question. At high engine speeds, shifting into 3rd gear is hard. But when I drive normal it shifts fine

Thank you for the video. In the winter months (or when it's say 40* F or below out) I will get a slight crunch when shifting from 1st to 2nd. Over ~40*F I have zero crunch at all. Obviously the fluid temperature is directly related to said crunch but I'm wondering why exactly said crunch is happening. Could the cold, thick fluid be causing the the synchro to spin slower than it should be, thus causing said crunch?? It's odd, but the crunch is ONLY on 1st to 2nd shifts when cold.

Thank You for uploading. Needed to see it to better understand.

Now I finally understand what's going on with my T56 when cold... makes sense.

This was an awesome explanation I appreciate it a lot!

Thanks for posting this! I was wondering, when you have a grind, does it cause metalk shavings or is the metal hard enough to prevent that?

I agree with everyone else. You did a great explanation I had seen some other ones and had no idea what they meant but you did it very well. Thank you.

Makes sense.. Thanks.. My 2nd & 5th gear grinds - im using an Opel astra F20 gearbox..

Thank you for this! I would love to know WHY my trans sometimes doesn't ingage into 2nd, and falls into false neutral, ESPECIALLY with how you just explained syncros. Thank you for what you do!

I bought a used car with 2 gear grinding problem. I thought it was the shift stick got problem. Now I know it is a sync problem in transmission. Although it is a bad news, yet still good to know. Maybe I could rev match better to get around it.

That was a beautiful explanation!

Ah, nice to finally understand what exactly is going on with the problematic 2004-2008 era Honda 6-speed transmissions in third gear.

Great explanation Jemal!!

Nice explanation

Thank you for the informative video. It's pretty simple. I thought it was something really complicated!

Very well detailed explanation and informative. Thanks

Solid video. Thank you! My 998A+ engine doesn't shift smoothly to 2nd. I presume that this is exactly what's going on.

Very good and simple explanation.

Wow! Nice explaination!

the best explanation on youtube, thank you!

How much typically to get new synchros installed? (2nd and 3rd mainly)

It is a pity that you kept pointing to one of the three pins on the outer periphery of the synchronising ring as at 0:33. The synchronising ring cannot be left floating in between the two adjacent rotating wheels and it MUST be always engaged to one of the wheel with those sliding pins as the synchronising collar/ ring cannot have affixed location with respect to both wheels, It would have been clearer to first explain the taper in the synchronising cones and then explain why the ring needs to be kept continuously engaged to one of the wheels where in addition to friction on the taper there may be a turbine effect where the rotating teeth would be reacting on the other set of teeth, but eventually it is " Friction" or the cone clutch which takes over the final action but as you said there must be that gap for the cone to bite home,

Perfect explanation. Thank you.

Awesome video. My 370Z just started grinding going into 5th. 160K miles on Z's never had something like this happen. This one only has 20K on it.

very helpful video! Yesterday my wife who drives an automatic all the time (but she knows how to drive manual basically and has done it before) sat in my VW Golf and when pushing the brake (as you do in AT) pushed it into reverse gear!! of course the car made a bad popping sound and stalled. I have been driving it normally since this happened and it seems OK and I cannot detect anything unusual yet. How worried should I be?! What should I be looking for?

Now I get it = Great job explaining!

now if only this guy could teach me heel toe as fast as he explained what happens when people grind gears

Wow awesome video I’m having this issue with my 10R80 transmission on low RPMs I’ll have to get it fixed asap

Thank you so much. Explained very well.This is the exact problem which i am facing.

I have no idea what any of this means but I watched the whole thing.

I seem to be getting some weird grinds on my RX-7 FC now and then on upshifts for no reason. Clutch is all in too. They've stopped happening lately. Currently it happens when I mess up on downshifts because I go too fast through the motions and sometimes the gear stick doesn't go into place as fast asI expect it to. I usually get them right though. Gonna take it a bit slower.

Nice and straightforward. Thanks.

thank you it's so clear now i have a problem withe my car chevrolet aveo 1.5 whene i put the 5 gear and i park the car the revers gear don't worck do you think i have a problem with the synchro ??

I have a 2014 Mazda 3, 6 speed which does that exact thing when changing from 1st to 2nd. It's only done 74000 kms. It's good to know why it's doing it!

This is absolutely great, thanks for sharing this.

Fantastic video and explanation , thank you

How can the collar push the ring in the first place if it slips all over the ring? And so all of the power to the wheels is transmitted through the small teeth?

Great explanation! I was having some transmission problems in my vehicle, getting an intermittent crunch when shifting from 3rd to 4th initially. Took it to a shop, they claimed to have fixed it, but even after returning to the shop for adjustments two separate times the crunching still persists. Now it likes to crunch sometimes when down shifting from 4th to 3rd and sometimes from 4th to 5th. It's strange because the shop can't replicate it and it only seems to happen after I've driven around town for at least 30 mins to an hour. I've tried to dwell longer between the clutch being depressed and moving the gear lever and tried being fast and precise while rev matching, same, sometimes a crunch sometimes no crunch. Any ideas? (They gave me the old syncros from the first shop visit.)

wow amazing video great description! now i know whats wrong with my bmw 6 speed transmission grinding in 3rd

ok so i have a 98 honda civic and it grinds constantly while in gear. would this be the same problem? can any one help?

I am as dumb as fuck and this video made sense to me......well explained dude, 🙏

thanks for the explanation. . my 4th gear synchronizer is shot.. by which I'm mean its nonexistent ,grinds and never engages so I go from 3rd to 5th.. my mechanic is working on it so I would like to know the cost of something like this.. my warranty cover the labor to bring down n put back the trans but it wont cover fixing the synchronizer.. what does a synchronizer repair cost n what's the wait time

That explains alot... makes sense... thanks for explaining 👍👍