The Difference between Synchronized and Unsynchronized Gearing in Manual Transmissions

By Mister Transmission

There’s a good reason why large commercial vehicles, motorcycles, and race cars still employ an unsynchronized gearbox

For stick-shift adherents, there is no greater joy than driving a car with a manual transmission. But what’s behind the mechanics of changing gears? And from a driver’s perspective, how does manual transmission synchronized gearing compare to manual transmission unsynchronized gearing?

Most modern urban vehicles fitted with manual transmissions likely feature a synchronized gearbox also referred to as a synchro-mesh gearbox. This device keeps the gears in mesh and rotating, or they can be locked to the shaft. In other words, when you change gears, you’re locking different gears to the transmission’s input or output shaft, thereby allowing you to increase your vehicle’s speed or slow it down. The manual transmission’s synchronized gearbox is what helps you smoothly lock gears into place.

It was a remarkable evolution in manual transmissions because the synchronizer did away with the need for motorists to perform double-clutching – releasing and re-engaging the clutch twice whenever changing gears – a requirement to operate a vehicle with a manual transmission unsynchronized gearbox.

Why the Manual Transmission Unsynchronized Gearbox Still Matters

A manual transmission unsynchronized gearbox is an older design (possibly the earliest design of a manual transmission) that required a lot of effort and skill on the driver’s part. It included a sliding-mesh gearbox, and the driver would need to carefully time when to shift gears to ensure the gears were rotating at the same speed, which was no easy feat. Do it improperly, and you’ll hear grinding and other noises.

However, the unsynchronized gearbox continues to exist. You will often find them installed in transmissions for large commercial vehicles such as heavy trucks and farming machinery, as well as in motorcycles and high-calibre race cars. Why? For two reasons: synchronized manual transmissions are more prone to breakdowns, and shifting gears on a synchro-mesh gearbox is slower than the unsynchronized version.

Are you experiencing a problem with your vehicle’s manual or automatic transmission or have questions about transmissions? Visit the Mister Transmission location nearest you and get the expert help and information you need.

image-reviews image-reviews
Customer Reviews
I'm Paul's neighbor and a...
Darryl Dalkeith
I'm Paul's neighbor and a review written about him washing the absorbant down the sewage drain is completely false. I saw him do the clean up of his driveway that got soaked with oil from working on his truck, after he soaked up the oil he shoveled the excess absorbant into the back of his truck then washed the remainder down to the end of this driveway and shoveled that into the back of his truck the only bit that went down the sewer was the dust that could not be shoveled up. It was a completely good professional job he did cleaning up the mess made..I enclosed a picture of the absorbant both wet and dry in the back of his truck to prove this point... read less
Date: September 2, 2024
Website: Google
Best place in town to...
Gushue's Landscaping
Best place in town to have any vehicle serviced and repaired. Honest, dependable and reliable service. Highly recommended.
Date: September 1, 2024
Website: Google
Brought my Honda Fit in...
Matthew Noonan
Brought my Honda Fit in for a clutch replacement, and they got it done quickly. Brian and Allen were both super helpful in the process.
Date: September 1, 2024
Website: Google
Mr. Transmission took my vehicle...
Larry Tetreault
Mr. Transmission took my vehicle in. Had a small leak. New exactly what they were doing. Did the job and did it well?
Date: September 1, 2024
Website: Google
Extremely kind and accommodating service...
Daniel Reichert
Extremely kind and accommodating service Always great experience at this Mr. Transmission
Date: August 31, 2024
Website: Google
This is one of the...
Natasha “Natasha”
This is one of the few repair shops I feel comfortable going to as a person who understands very little about cars. The people at the shop are friendly, they clearly explain your options, they do not charge you simply because they can, and are very fair. They also have a cute dog that is super friendly and helps to relieve stress.
Date: August 31, 2024
Website: Google
Giving a 4 for their...
Dazzler
Giving a 4 for their pleasant service. Nice people to deal with. Was surprised with an appointment it took 9 days to get my car back with 14 hours labour noted, but runs well so happy I'm running well again. $4850 bill hurt huge! Relieved for 1 year warranty.
Date: August 30, 2024
Website: Google
Darren and crew did an...
Gord Beilner
Darren and crew did an excellent job. Very informative and respectful of our concerns. We will not hesitate to recommend their services to others. Job well done.
Date: August 30, 2024
Website: Google
Excellent service and very thorough....
Lisa LoStracco
Excellent service and very thorough. Great job! Cory and Casey absolutely awesome to work with!
Date: August 30, 2024
Website: Google
Giving a 4 for their...
Dazzler
Giving a 4 for their pleasant service. Nice people to deal with. Was surprised with an appointment it took 9 days to get my car back with 14 hours labour noted, but runs well so happy I'm running well again. $4850 bill hurt huge! Relieved for 1 year warranty.
Date: August 30, 2024
Website: Google
Featured Services
Transmission Repair

The evolution of transmissions has made these machines and systems increasingly complex. When transmission repairs are required, determining the cause and cure for what ails can be tricky.

Read More
Transmission Technology

At Mister Transmission we have access to leading-edge diagnostic equipment, enabling us to offer you the fastest and most accurate findings about what’s going on inside your vehicle’s transmission.

Read More
Transmission Maintenance & Service

Just as you have other parts of your car serviced, your transmission needs maintenance to ensure a long life and avoid transmission problems.

Read More
Mister Transmission Blogs
Recent Blogs
The Lifespan Of A Repaired Transmission
Maintaining the health of your vehicle's transmission is crucial for its overall
Read More
August 28, 2024
Why Transmission Repairs Can Be Expensiv...
Transmission repairs are one of the most significant automotive expenses a vehicle
Read More
August 21, 2024
Can Driving With A Bad Transmission Dama...
Driving with a malfunctioning transmission can cause serious damage to your vehicle.
Read More
August 14, 2024
The Costs Of Transmission Repairs: What ...
Transmission repairs can be a significant financial burden for car owners.
Read More
August 9, 2024
Should You Repair Or Replace Your Transm...
When faced with transmission problems, many car owners grapple with the decision of
Read More
July 31, 2024
How Long Does A Transmission Repair Take...
Transmission repair is a critical aspect of vehicle maintenance that ensures your car
Read More
July 23, 2024
Common Signs Of Transmission Trouble
Transmission problems can cause significant issues if left unaddressed, leading to
Read More
July 15, 2024
Is It Worth Fixing A Bad Transmission? A...
When your vehicle's transmission starts showing signs of trouble, it can be a
Read More
July 5, 2024
Why Your Transmission Shop Choice Matter...
In the ever-evolving automotive landscape of 2024, selecting the right transmission
Read More
June 28, 2024
Transmission Repair Vs. Replacement: Mak...
Understanding the condition of your vehicle's transmission is pivotal for its
Read More
June 21, 2024