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STC8577 - Synchro Unit Land Rover Range Rover Defender, Discovery, Range Rover

STC8577 - Synchro Unit

- €270,00
€270,00
€270,00 - €270,00
€270,00
OEM Part
OEM: Made by an Original Equipment Manufacturer. This part is made by an original equipment manufacturer or under their license, ensuring compatibility and quality.
Synchro Unit - the 1st/2nd gear synchromesh assembly carried on the mainshaft of the LT77 five-speed manual gearbox.

The synchro hub is splined to the mainshaft and carries the sliding sleeve that the selector fork moves. As the sleeve advances, the baulk ring brings the free-running gear up to mainshaft speed before the dog teeth engage, giving a clean shift without clash.

Worn synchro components show as a crunch or a baulk when selecting first or second gear, most noticeable on a cold gearbox.
Vehicle Model Land Rover Defender up to 2016
Land Rover Discovery 1 1989-1998 (L318)
Range Rover Classic up to 1994
Fitment Notes DEFENDER 1987-2006 — LT77 5-speed manual, 1st & 2nd mainshaft synchroniser assembly
DISCOVERY 1 1989-1998 — LT77 4-cyl & V8, gearbox suffix H
RANGE ROVER CLASSIC 1992-1994 (from VIN JA610294) — LT77 manual, 1st/2nd/5th mainshaft
Alternative Codes
STC857719941ST/2NDLT77

Available to order 2–3 weeks

Not currently in stock. Order now — typically ships within 2–3 weeks.

Need it faster? Contact us about express import (2–5 business days).

When will my order arrive?

This item is ordered from our supplier on request. Typical lead time is 2–3 weeks from order confirmation.

  • Netherlands / Belgium / Germany: 2–4 working days after dispatch.
  • Other EU countries + UK: 4–8 working days after dispatch.
  • Outside EU/UK: contact us for an estimate.

Need it faster? Express import available in 2–5 business days — contact us before ordering.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What is the STC8577 synchro unit?
The STC8577 is the 1st and 2nd gear synchroniser assembly for the LT77 5-speed manual gearbox. It sits on the mainshaft and lets the gears mesh smoothly when you change between 1st and 2nd.
Which vehicles use this LT77 synchro?
The STC8577 fits the LT77 gearbox in the Defender (1987-2006), Discovery 1 (1989-1998, 4-cyl and V8, suffix H), and Range Rover Classic (1992-1994 from VIN JA610294). It covers the 1st/2nd position on all three.
What are the signs the synchro needs replacing?
A worn 1st/2nd synchro on the LT77 gearbox typically shows as crunching or baulking when shifting into those gears, especially when cold. Replacing the STC8577 restores clean shifts, and it's usually done during a gearbox rebuild.