Aston Service Dorset : DB2/4 MkIII Transmission
      Aston Service Dorset : Aston Martin DB2 + DB2/4 MkI - MkII  

     Clutch (Plate H)
     Gearbox, Gears (Plate J)
     Gearbox, Overdrive (Plate K)
     Gearbox, Top Cover (Plate L)
     Rear Axle (Plate N)


  Fuel, Cooling + Exhausts

  Suspension + Steering

  Brakes + Pedal Gear

  Electrical + Instruments

  Chassis, Frame, Body, etc.
    For all Parts Catalogues, Workshop Manuals and Instruction Books please follow the link to the technical publications page.

Aston Service Dorset : Transmission

A selection of the most frequently asked for Transmission parts are shown below as they appear in the Parts Book (Part Number 90222), anything that is not there, contact us and we will be happy to advise on stock and availability:

Aston Service Dorset : The Clutch

The clutch is a 9" single dry plate Borg and Beck with carbon ring thrust pad which is hydraulically operated that requires little or no attention until considerable mileage has been covered, replacements are available as detailed below.

Aston Service Dorset : Clutch Cover Assembly   74840



  Cover Assembly

Release Bearing Assembly

Retaining Spring

Driven Plate Assembly

Back to top

Aston Service Dorset : Gearbox

The David Brown four-speed synchromesh gearbox is mounted integrally with the clutch housing and is supported at the rear rubber mounting.

A Laycock de Normanville overdrive unit was an optional extra that could be fitted to the car, a final drive ratio of 4.09:1 was recommend for cars fitted with the overdrive.

One of the following two boxes may be fitted and they are distinguished by the following four letter codes:

DBCC - Close Ratio (Centre change)

DBCW - Wide Ratio (Centre change)

There are a few replacement parts available and the more frequently asked for ones are below:

Aston Service Dorset : Bearing Ball Hoffman   51019   Bearing, Ball, Hoffman, Rear
Aston Service Dorset : Gearbox Oil Seals   55963

  Oil Seal Rear

Oil Seal Front
Aston Service Dorset : Tab Washer   55905   Tab Washer

Back to top

Aston Service Dorset : Gearbox

Aston Service Dorset : Overdrive Conversion   54354C   Overdrive Conversion for MkIII cars not already fitted.

Cars with chassis numbers AM300/3/1300 to 1400 will require modifications to the chassis to accept the conversion

Back to top

Aston Service Dorset : Gearbox

Aston Service Dorset : Gear Knob   56004   Gear Knob with 5/16" BSF thread to fit original gear shaft
Aston Service Dorset : Gear Lever Retaining Plate Bolt and Spring   56002

  Gear Lever Retaining Screw

Gear Lever Retaining Plate Spring

Back to top

Aston Service Dorset : Propellar Shaft

Power is transmitted to the rear live salisbury axle through an open type Hardy Spicer shaft with both propeller shaft universal couplings being needle roller types.

Availability of parts for the 4HA is good, contact us for further details and prices.

The following is a selection of replacement parts that are available for the 4HA Axle.

Aston Service Dorset : Axle Shaft   20-26-743




  Axle Shaft

Bearing, Taper Roller

Seal, Oil, Axle Shaft

Bearing, Axle Shaft
Aston Service Dorset : Nut and Key Axle Shaft   56858


  Nut, Axle Shaft

Key, Axle Shaft

Split Pin 5/32"

Aston Service Dorset : Rear Hub and Studs   77660



  Hub Assembly, Rear (Nearside)

Hub Assembly, Rear (Offside)

Stud, Brake Drum

Nut, Self Locking
Aston Service Dorset : Gasket Gear Carrier and Oil Seal   55133

  Gasket, Gear Carrier Cover

Seal, Oil, Pinion Bearing
Aston Service Dorset : Differential Case Crown Wheel and Pinion Assembly   20-26-789


  Case Assembly, Differential

Crown Wheel and Pinion Assembly 3.77:1 ratio

Screw, Set, Wheel to Differential Case
© 2009 Aston Service Dorset   Back to top