Gearbox Anchors / Stops / Blocks
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- 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 915 Gearbox 5 Speed
Manual transmission
This kit is comprised of the following items:
- 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 45.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
92830232100
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 45.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
92830232100
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 38.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
92830232200
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
3 per gearbox - sold each.

Fits:
Porsche 911 1974-86 (915 Gearbox)
Diagram Ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91130231701
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
3 per gearbox

Fits:
Porsche 911 1974-86 (915 Gearbox)
Click "Zoom in" to see the diagram.
Diagram Ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91130231701
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
A genuine Porsche transmission thrust piece (sometimes called a transmission anchor block or synchro thrust block) originally fitted in the 915 manual gearbox used on classic Porsche models. This piece is typically replaced when rebuilding or overhauling the gearbox to ensure all internal parts meet the required wear and tolerance standards.
Sold each, 2 required per gearbox.
Fits:
Porsche 911 1974 - 1986 (915 Gearbox)
Diagram Ref no 44.
It is a small yet critical component inside the classic 915 manual gearbox that interfaces with first and second gear synchro assemblies, helping to locate and support internal gears and synchroniser parts
Inside the gearbox, the thrust piece serves as a structural support and alignment block for the first and second gear synchroniser assembly. It helps maintain the proper spacing and alignment of moving gear train components under load, ensuring the gearbox shifts smoothly and reliably into first and second gear.
Transmission internals operate under high loads and precise mechanical conditions. Over time, even small parts like the thrust piece can wear, deform, or lose proper tolerances, causing:
• Gear engagement issues
• Increased synchroniser wear
• Unwanted gearbox noise or shudder
• Reduced shift quality
Replace this thrust piece if:
• You are performing a complete gearbox rebuild
• Internal transmission wear is present
• Synchroniser engagement is not smooth
• Accurate gear spacing and alignment need restoration
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91530231502
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
Supports the synchroniser and gear assembly within the gearbox, particularly relating to first and second gear. It is manufactured as a direct-fit component designed to replicate the form, fit, and function of the factory part.
Sold each, 2 required per gearbox
Fits:
Porsche 911 1974 - 1986 (915 Gearbox)
Diagram ref no 44.
Inside the 915 manual gearbox, the thrust block plays a critical role in maintaining correct alignment and support for the synchroniser assembly, particularly between first and second gears. It helps maintain correct spacing and load distribution on internal transmission components, ensuring consistent gear engagement and smooth shifts.
By accurately positioning and supporting the gears and synchronisers, this thrust block helps reduce internal wear and supports reliable transmission operation - especially under spirited driving conditions common in performance Porsche use.
Transmission internals operate under high rotational and axial loads, meaning even small variations in spacing or fit can lead to friction, wear, or mis-engagement. A worn or poorly fitting thrust block can cause:
• Gear engagement issues
• Increased synchroniser or gear wear
• Rough or imprecise shifting
• Premature transmission component failure.
Replace this transmission thrust block if you are:
• Performing a full gearbox rebuild
• Noticing rough or imprecise shifting in first/second gear
• Reassembling a gearbox with worn internal components
• Addressing synchroniser wear or axial play
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91530231502
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
3 per gearbox

Fits:
Porsche 911 1974-86 (915 Gearbox)
Click "Zoom in" to see the diagram.
Diagram Ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93030232511
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
3 per gearbox

Fits:
Porsche 911 1974-86 (915 Gearbox)
Click "Zoom in" to see the diagram.
Diagram Ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93030232511
The product you are viewing cross references to these numbers
Porsche Gearbox Anchors, Stops & Blocks | Secure Transmission Positioning & Drivetrain Control
Gearbox anchors, stops, and blocks are vital structural components that stabilise and secure your Porsche’s gearbox under torque load. These parts prevent unwanted gearbox movement, maintain proper alignment with the engine and driveshafts, and protect surrounding components from vibration or stress.
At Design911, we supply precision-engineered gearbox anchors, stops, and mounting blocks designed to match or exceed original performance standards. Crafted from high-strength aluminium, steel, or reinforced polymer, these components ensure optimal gearbox stability under both road and performance conditions.
Whether you’re replacing worn anchors on a daily driver or upgrading a track-prepared Porsche, our gearbox anchors and stops deliver improved drivetrain control, reduced vibration, and long-term reliability.
What Do Gearbox Anchors, Stops & Blocks Do?
These components serve as the mechanical connection points that keep the gearbox firmly in place while allowing controlled movement during acceleration and braking.
Core Functions:
- Maintain correct gearbox alignment within the chassis.
- Absorb torque loads to prevent drivetrain movement.
- Support consistent gear engagement and shifting precision.
- Reduce vibration and protect mounts, linkages, and couplings.
Without properly functioning gearbox anchors or stops, the transmission can shift under load — causing excessive movement, misalignment, or even component damage during gear changes or hard acceleration.
Why Do Gearbox Anchors, Stops & Blocks Fail or Wear Out?
Over time, continuous stress, heat, and vibration weaken or deform these components, especially in high-performance or ageing vehicles.
Common Causes of Failure Include:
- Metal fatigue or cracking under torque stress.
- Corrosion or oxidation from road debris or moisture.
- Rubber or polymer degradation in hybrid anchor designs.
- Damage from harsh impacts or poor alignment.
- Loose fittings or worn mounting bolts causing play.
Once compromised, gearbox anchors can allow excess movement — resulting in drivetrain noise, gear misalignment, or premature wear to transmission mounts and couplings.
Why Replace Your Porsche Gearbox Anchors, Stops & Blocks?
Replacing worn or damaged gearbox anchors ensures your transmission remains securely mounted, properly aligned, and free from unwanted movement. Upgraded anchors or reinforced stops enhance stability and control, particularly in modified or high-performance Porsches.
Key Benefits:
- Restores proper gearbox alignment and support.
- Prevents driveline movement and gear misalignment.
- Reduces vibration, noise, and stress on surrounding parts.
- Improves gear change accuracy and drivetrain feel.
- Constructed from high-strength materials for long life.
- Suitable for road, restoration, or track applications.
For optimal performance, anchors and stops should be inspected and replaced during clutch, mount, or gearbox servicing.
Highlights
- Premium Porsche gearbox anchors, stops, and blocks.
- Designed for strength, precision, and long-term durability.
- Minimises drivetrain movement and vibration.
- Perfect fitment for Porsche 911, Cayman, Boxster, and more.
- Reinforced for performance, restoration, or repair use.
- Essential for maintaining transmission stability and balance.