Synchroniser Ring Gearbox | 3rd Gear | 4th Gear

Synchroniser ring for gearbox.
Sold each.
VW Beetle 3rd and 4th gear - from 10/61 onwards.

Synchroniser rings are used to ensure smooth engagement of the gears. The synchroniser rings ensure that the speeds of the shaft and gear are equal when engaging. From 8/1960 Volkswagen offers a fully synchronised gearbox for most versions, except for reverse gear. This is also noticeable because the gear sometimes wants to crunch when shifting into reverse. The gears of the disengaged cogs turn freely around the output shaft. Engaging a gear therefore means coupling a freely turning gear to the output shaft. When a gear is engaged, the speed of the output shaft must match the speed of the gear to be engaged. The gear to be engaged has a different speed from the output shaft, so also a different speed from the synchroniser hub. As the shift fork moves, it takes the synchroniser along and the conical part of the synchroniser ring is pressed against the inner conical surface of the gear. The conical parts of the two are pressed against each other, balancing the friction between the conical surfaces. When there is no longer a speed difference between the two gears, the gear sleeve can be pushed through, so the teeth slide together and the gear is engaged. The synchronisation works not only when shifting up but also when shifting down. It is very bad for the synchroniser rings to change gears very quickly, i.e. pushing the gear lever very hard into a gear. The synchroniser does not get time to synchronise. It is therefore best to push the gear lever gently against the resistance when shifting and only push it through when it is almost in gear by itself. A synchroniser ring is a wear part. During shifting friction occurs, so the part wears over time. When dismantling the gearbox the synchroniser rings can be checked for wear. With a feeler gauge the gap between the synchroniser ring and the gear can be measured. The gear should not be engaged. If the synchroniser ring is worn, the gap between the synchroniser ring and the gear decreases. Your workshop manual describes the wear limit of the synchroniser ring. If the measured value is smaller than the maximum wear value in the workshop manual, it has to be replaced. Supplied individually.

Caution: only suitable for fully synchronised gearboxes.

4001422 Application: for first and second gear
Beetle: all years
Karmann Ghia: all years
Bus: from 8/1967 to 7/1975
Type 3: all years
Type 181 (Thing): all years

4001423 Application: for third and fourth gear
Beetle: from 1961 (chassis no. 4 274 401) onwards
Karmann Ghia: from 1961 (chassis no. 4 274 401) onwards
Bus: from 8/1967 to 7/1975
Type 3: all years
Type 181 (Thing): all years