M32 Gearbox 3rd / 4th Gear Synchromesh Hub Gen 1 & 2 55570102 Vauxhall

M32 Gearbox 3rd & 4th Gear Synchromesh Hub (Gen 1 & 2) – Vauxhall, Opel, Fiat, Alfa Romeo, Chevrolet & Saab

This is the 3rd & 4th gear synchromesh (synchro) selector hub for the M32 6-speed manual gearbox, fitment location 24 on the gearbox diagram. The synchromesh is one of the most common wear items on the M32 — a worn or faulty synchro causes a crunching or grinding noise when changing gear and, left unrepaired, goes on to damage the gear and hub. This assembly contains one synchromesh with detents for use on 3rd and 4th gear.

Important – generation fitment: This part fits the Gen 1 & 2 M32 only. The Gen 1 & 2 gearbox uses a different tooth cut, synchromesh and hub design and is not compatible with the Gen 3 M32 gearbox (2016 onward).

Fits transmission: M32 6-speed manual gearbox (Gen 1 & 2)

OE / part number: 55570102

Fitment location: 24 on the M32 exploded diagram

Vehicle Compatibility

Abarth

• Grande Punto (199), 2007–2009
• Punto (199), 2012–2014
• Punto Evo (199), 2010–2012

Alfa Romeo

• 147 (937), 2000–2010
• 156 (932), 1997–2007
• 159 (939), 2005–2011
• Brera (939), 2006–2011
• Giulietta (940), 2010–2021
• GT (937), 2004–2011
• Mito (955), 2008–2020
• Spider (939), 2006–2011

Chevrolet

• Cruze (J300/J305/J308), 2009–2014
• Orlando (J309), 2010–2014
• Trax / Tracker, 2013–2014
• Aveo (T300), 2011–2014
• Malibu (V300), 2011–2015
• Cruze USA/CAN (J300), 2010–2016
• Cruze USA/CAN, 2016–2020
• Sonic (T300), 2012–2020

Opel

• ADAM (M13), 2013–2019
• Astra H (A04), 2004–2010
• Astra H TwinTop (A04), 2006–2010
• Astra J (P10), 2009–2018
• Astra K (B16), 2015–2022
• Cascada (W13), 2013–2019
• Corsa D (S07), 2006–2015
• Corsa E (X15), 2015–2019
• Insignia A (G09), 2008–2017
• Insignia B (Z18), 2017–2022
• Meriva A (X03), 2003–2010
• Meriva B (S10), 2010–2017
• Mokka (J13), 2012–2016
• Mokka X (J13), 2016–2019
• Zafira B (A05), 2005–2014
• Zafira C (P12), 2012–2019
• Signum (Z03), 2003–2008
• Vectra C (Z02), 2002–2009

Vauxhall

• ADAM (M13), 2013–2019
• Astra H (A04), 2004–2010
• Astra H TwinTop (A04), 2006–2010
• Astra J (P10), 2009–2018
• Astra K (B16), 2015–2022
• Cascada (W13), 2013–2019
• Corsa D (S07), 2006–2015
• Corsa E (X15), 2015–2019
• Insignia A (G09), 2008–2017
• Insignia B (Z18), 2017–2022
• Meriva A (X03), 2003–2010
• Meriva B (S10), 2010–2017
• Mokka (J13), 2012–2016
• Mokka X (J13), 2016–2019
• Zafira B (A05), 2005–2014
• Zafira C (P12), 2012–2019

Fiat

• Bravo (198), 2007–2015
• Croma (194), 2005–2010
• Grande Punto (199), 2005–2011
• Linea (323), 2007–2014
• Punto Evo (199), 2009–2012

Saab

• 9-5, 2010–2011

FAQs

How do I know if my M32 synchro hub needs replacing?

Crunching or grinding when selecting 3rd or 4th gear, or the gear baulking or popping out, usually points to a worn synchromesh. Left unrepaired it can damage the gears and hub.

Will this fit my M32 gearbox?

It fits Gen 1 & 2 M32 6-speed gearboxes. It does not fit the Gen 3 M32 (2016 onward), which uses a different tooth cut and hub design.

What is included?

One 3rd & 4th gear synchromesh selector hub assembly with detents (OE 55570102).

Is this a genuine part?

Yes — this is a genuine OE-specification synchromesh hub.

Why Choose Eco Torque?

As specialists in gearbox rebuilds and repairs, Eco Torque takes pride in offering genuine gearbox parts, high-quality aftermarket alternatives and competitive pricing.

Need Help Finding the Right Part?

If you are unsure whether this part is compatible with your vehicle, send us your UK registration number or VIN and we will help you find the correct part.

Reference Number: ET2339