Synchromesh unit (Manual Car Transmission) - How it works

This video explains the operation of a synchromesh unit in a typical manual transmission, detailing synchromesh (blocker/baulk ring) operation.
The Synchromesh AKA Constant Mesh gearbox is an improvement on the older sliding mesh gearbox which relied heavily on driver skill and double-clutching to not grind or crunch the gear change. The sliding mesh box was also known as a "crash box" due to the gears making lots of noise when changing.

The particular synchro unit used in this video is from a Land Rover LT77 manual gearbox but the information applies to most synchromesh manual shift transmissions in vehicles today. Synchro rings.

Camera gear used in this video:

[jamessparks]

It's amazing that humans are capable of making such complicated machinery. You have to be a genius at this kind of stuff to come up with a system like this.

[outcast]

As much as I love 3d Animations, it is nice to see the components in action and this was honestly the first time that I got to see a working manual transmissions go through the motions with a cutaway so that you can see...Thank you for posting...

[franic_scopes]

You have explained what absolutely nobody has done in any other video I have found. Thank you.

[AlexTheGreatish]

I am really high and this just blew my mind.

[Kitteh.B]

Got curious about synchros after midnight and this video was the best of the bunch for explaining AND visualizing what was going on. Thank you!!

[ColinMill]

Very good. Should be recommended viewing for anyone learning to drive a manual transmission car.

[TheNicky]

Awesome! My young nephew asked me how syncro worked and I struggled to explain it, your simple but understandable explanation was a godsend, well done and thanks for your great description and video of how it works, in fact I learnt a thing or two as well :)

[jetmr_]

I’m in the process of rebuilding my brother’s ‘51 ford 3 speed with a borg Warner t10 overdrive. I wasn’t completely sure how his syncro’s worked, but this video makes perfect sense to me! Thank you!

[jetrider]

Awesome amazing easy way to explain a complex machine.
My son is starting to drive my car and your video was the very 1st one to make him understanding how magics works inside the gearbox. Thanks mate.

[TheOgre]

Fantastic explanation and demo of how this works!! Couldn't quite understand how it worked until finding this video.

[HelenaOfDetroit]

That's a brilliant explanation. Thanks for the video!

I own a 2017 Jeep Wrangler, and the transmission has had issues going into reverse. I took it to a mechanic, and he mentioned that it's a common problem with manual transmissions from Jeep at the time. He said it was due to the way they designed the Synchromesh.

Now I just have to redesign it so I can make new parts and fix the issue. One day....

[leodooley]

Brilliant short, clear and to the point visual and audio presentation. Now I understand.

[adrianpolley]

A really straightforward and easy to follow explanation. Many thanks .

[mtvoeyn]

dude sounds just like the Geico lizard.

[mustaphabouchnita]

The most wonderful simple and easy explanation I have ever seen. Thank you very much.

[kiwzich]

I have rebuilt a couple of these transmissions successfully and I still am not sure if I understand just how they work. Thanks for the video. Amazing how someone or a team came up with the original design.

[EB_]

Best way to learn is seeing it happening. Thank you for the video.

[RaviPatel-fvhu]

please make more videos like this sir 🙏🙏 this was the best explanation for synchromesh gear box 👍

[JossPretty]

thanks so much for the slo mo shots! really helps understand the whole process

[TheTonester]

What a complicated thing to break down. Very nice 🙏🏽