do not press the back button…
Enter your VAT number here and click Verify:
Your details have been verified. VAT number registered to:
,
.
Your order will now be zero rated for VAT purposes. We reserve the right to verify these details after your order request has been made and reinstate VAT if required.
Your VAT details were not recognised or were invalid. Your VAT number must be matched to your Billing Country as specified above. This is currently specified as . You do not need to enter the country code part of your VAT number as this has already been selected in your billing address details above.
The VAT number checking service is currently offline. Please supply your VAT details within the comments or special instructions field below and we will apply a VAT discount after placing your order request.
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Synchro Guide Hub 91530240102 1st/2nd Gear – 915 Gearbox
Restore the crisp shifting performance of your classic
Porsche 911 with this OE Match Synchro Guide Hub. Designed specifically for Porsche 911 models fitted with
the legendary 915 gearbox between 1974 and 1986, this precision-engineered
component forms a critical part of the 1st and 2nd gear synchroniser assembly,
helping to ensure smooth gear engagement and reliable transmission operation.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Diagram Ref no 41
Manufactured to OE specifications, this replacement synchro guide hub delivers the correct fit, strength and dimensional accuracy required for professional gearbox rebuilds and classic Porsche restorations. Whether you're addressing worn synchroniser components, improving shift quality or carrying out a complete transmission overhaul, replacing worn guide hubs helps restore factory gear change performance.
What Does the 1st/2nd Gear Synchro Guide Hub Do?
The synchro guide hub is a central component within the Porsche 915 gearbox synchroniser assembly. Located between 1st and 2nd gears, it provides the mounting and guidance structure for the synchroniser mechanism and works in conjunction with the operating sleeve, synchro rings, brake bands and anchor blocks.
Its primary function is to facilitate smooth gear engagement by helping synchronise the rotational speeds of the gears before they lock together.
The guide hub helps:
- Support the synchroniser assembly.
- Control movement of the operating sleeve.
- Facilitate smooth 1st and 2nd gear engagement.
- Reduce gear clash during shifting.
- Maintain accurate gear selection.
- Improve overall gearbox operation and shift quality.
A properly functioning guide hub is essential for preserving the characteristic feel and reliability of the Porsche 915 transmission.
Why Do Synchro Guide Hubs Fail?
Over decades of service, synchroniser components are subjected to constant mechanical stress and repeated gear changes. Wear and fatigue can gradually affect the guide hub and surrounding synchroniser parts.
Common causes of failure include:
Because 1st and 2nd gears are often the most frequently used ratios, the synchroniser assembly in this area of the gearbox is commonly one of the first sections to show wear.
When Should a Synchro Guide Hub Be Replaced?
The synchro guide hub should be inspected whenever the
gearbox is dismantled or rebuilt. Replacement is recommended if you experience:
Difficulty
engaging 1st or 2nd gear.
Most Porsche transmission specialists recommend replacing worn synchroniser components during a gearbox overhaul to ensure consistent performance and maximise gearbox longevity.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91530240102
The product you are viewing cross references to these numbers
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
The OE Match Synchro Shifting Sleeve, 1st/2nd Gear is a high-quality replacement transmission component designed to facilitate the engagement of first and second gears within Porsche manual gearboxes. Manufactured to OE specifications for fit, precision and durability, this shifting sleeve forms a critical part of the synchroniser assembly, ensuring smooth, accurate and reliable gear selection.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Diagram Ref No 42
Working in conjunction with the synchroniser hub, synchro rings and dog teeth, the shifting sleeve slides across the synchroniser assembly to engage the selected gear once rotational speeds have been synchronised. Precision machining and correct fitment are essential for maintaining shift quality, reducing gearbox wear and ensuring dependable transmission performance.
What This Product Does:
- Engages first and second gears within the gearbox.
- Works with the synchroniser assembly to enable smooth gear changes
- Transfers movement from the gear selector mechanism to the selected gear.
- Helps ensure accurate and positive gear engagement.
- Supports proper synchronisation before gear selection.
- Reduces gear clash and transmission wear.
- Contributes to smooth manual gearbox operation and drivability.
Symptoms Of Wear Or Failure:
- Difficulty engaging first or second gear.
- Gear grinding or crunching during shifts.
- Notchy or inconsistent gear changes.
- Excessive resistance when moving the gear lever.
- Gear disengagement or jumping out of gear under load.
- Poor shift quality and reduced transmission precision.
- Increased gearbox noise during gear changes.
- Visible wear, chipping or rounding of engagement surfaces during inspection.
Why Replacement Matters:
- The synchro shifting sleeve experiences repeated mechanical loading every time first or second gear is selected. Over time, the engagement surfaces can wear, become rounded or suffer damage, reducing the sleeve's ability to engage gears cleanly and securely.
- A worn shifting sleeve can compromise gear engagement, place additional strain on synchroniser rings and dog teeth, and accelerate wear throughout the gearbox. If left unresolved, continued operation may lead to increasingly poor shift quality and more extensive transmission repairs.
- Replacing a worn synchro shifting sleeve restores accurate gear engagement, improves transmission performance and helps protect other synchroniser components from premature wear. An OE Match replacement provides factory-style fitment, precision manufacturing and long-term durability, ensuring smooth and reliable shifting performance for your Porsche manual transmission.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93030241103
The product you are viewing cross references to these numbers
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Fits:
Porsche 911 1974-86 (915 Gearbox)
Click "Zoom in" to see the diagram.
Diagram Ref no 13.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91130241128
The product you are viewing cross references to these numbers
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Synchro Guide Sleeve 3rd/4th Gear – 915 Gearbox
Restore the precise shifting performance of your classic
Porsche 911 with this OE Match 3rd/4th Gear Synchro Guide Sleeve, designed
specifically for Porsche 911 models equipped with the renowned 915 gearbox
between 1974 and 1986. As a critical component within the synchroniser
assembly, the guide sleeve helps ensure smooth gear engagement and accurate
gear selection between third and fourth gears.
Fits:
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
Diagram Ref no 12
Manufactured to OE specifications, this replacement synchro guide sleeve provides the correct fit, machining accuracy and durability required for Porsche transmission rebuilds and restorations. Whether you are addressing gear selection issues, carrying out a gearbox overhaul or restoring a classic air-cooled 911, replacing worn synchroniser components is essential for maintaining smooth and reliable gear changes.
What Does the 3rd/4th Gear Synchro Guide Sleeve Do?
The synchro guide sleeve is a vital component within the Porsche 915 gearbox synchroniser assembly. It works alongside the synchroniser rings, brake bands, anchor blocks and operating sleeves to allow gears to engage smoothly and without excessive wear.
When a gear change is made, the guide sleeve helps control the movement of the synchroniser mechanism, ensuring rotational speeds between gears are matched before engagement occurs.
The guide sleeve performs several important functions:
- Guides synchroniser operation during gear changes.
- Supports smooth engagement of 3rd and 4th gears.
- Helps synchronise gear speeds before engagement.
- Reduces gear clash and transmission wear.
- Maintains precise gear selection.
- Contributes to the distinctive shifting feel of the Porsche 915 gearbox.
Without a properly functioning guide sleeve, gear engagement quality can deteriorate significantly.
Why Do Synchro Guide Sleeves Fail?
The synchroniser system experiences constant mechanical loading during every gear change. Over time, wear and fatigue can affect the guide sleeve and associated synchroniser components.
Common causes of failure include:
- Wear from repeated shifting cycles.
- Metal fatigue over high mileage.
- Poor lubrication caused by contaminated gearbox oil.
- Aggressive or incorrect shifting techniques.
- Excessive wear in synchroniser assemblies.
- Gearbox overheating.
- General age-related component deterioration.
As many Porsche 911 models equipped with the 915 transmission are now several decades old, wear within the synchroniser system is extremely common and often contributes to poor shift quality.
When Should a Synchro Guide Sleeve Be Replaced?
The synchro guide sleeve should be carefully inspected
whenever the gearbox is dismantled. Replacement is recommended if you
experience:
Difficulty
selecting 3rd or 4th gear.
Most transmission specialists recommend replacing worn synchroniser components during a gearbox overhaul to restore optimal shift quality and prevent premature future wear.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91130240222
The product you are viewing cross references to these numbers