| Description | Date | Identifier | |
| Wraith II gearbox extension, rear unit support, and the use of a Silentbloc rubber bush. | 17th Jul 1936 | Box 8 \ 11 11-page036 | |
| Instruction regarding hardened and unhardened surfaces for the Wraith II gearbox splines and shafts. | 8th Aug 1936 | Box 8 \ 11 11-page037 | |
| Frame stiffeners and modifications for the Wraith II Gearbox. | 8th Aug 1936 | Box 8 \ 11 11-page038 | |
| Rearrangement of studs for the Wraith II Gearbox rear top cover. | 10th Aug 1936 | Box 8 \ 11 11-page039 | |
| Oil communication within the Wraith II gearbox and the potential solution of using a cork. | 13th Aug 1936 | Box 8 \ 11 11-page040 | |
| Modifications to the Wraith II gearbox, specifically the gear gate and lever. | 17th Aug 1936 | Box 8 \ 11 11-page041 | |
| Spring rings and bearing grooves for the Wraith II gearbox. | 24th Aug 1936 | Box 8 \ 11 11-page042 | |
| New design for the Wraith II gearbox and the modification of splines on the 2nd motion shaft. | 13th Oct 1936 | Box 8 \ 11 11-page043 | |
| Confirming the task of fitting a Wraith gearbox to an independent suspension Bentley. | 16th Oct 1936 | Box 8 \ 11 11-page044 | |
| The Simplified Speedo Drive for the Wraith II gearbox, discussing savings and design objections. | 24th Oct 1936 | Box 8 \ 11 11-page045 | |
| Design of the Wraith II gearbox and its 2nd speed coupling. | 5th Nov 1936 | Box 8 \ 11 11-page046 | |
| Request to modify the 3rd speed bush and oil hole placement for the Wraith TT Gearbox. | 9th Nov 1936 | Box 8 \ 11 11-page047 | |
| Retaining plate for the Wraith II gearbox change gear gate. | 23th Nov 1936 | Box 8 \ 11 11-page048 | |
| Production hold-up on the Wraith II gearbox and the introduction of new parts to resolve it. | 26th Nov 1936 | Box 8 \ 11 11-page049 | |
| Alterations to the Wraith II Gearbox spline design for cost reduction and manufacturing practice. | 30th Dec 1936 | Box 8 \ 11 11-page050 | |
| Suggesting a change from forging to die-casting for the Wraith II Gearbox selector plunger housing to reduce costs. | 31th Dec 1936 | Box 8 \ 11 11-page051 | |
| Cost-reducing modification to the Wraith II Gearbox reverse shaft bearing. | 11th Jan 1937 | Box 8 \ 11 11-page052 | |
| The material change of plugs for the Wraith II gearbox. | 14th Jan 1937 | Box 8 \ 11 11-page053 | |
| Modification to the Wraith TT Gearbox's central diaphragm to improve oil flow. | 19th Jan 1937 | Box 8 \ 11 11-page054 | |
| Secret memo regarding drawing N.Sch.5006, which shows the centralised lubrication pipes for the Wraith II gearbox and clutch unit. | 19th Jan 1937 | Box 8 \ 11 11-page055 | |
| Modification to the Wraith II gearbox, using an aluminium die-cast cover. | 21th Jan 1937 | Box 8 \ 11 11-page056 | |
| Modification to the first speed selector lever on the Wraith II Gearbox. | 21th Jan 1937 | Box 8 \ 11 11-page057 | |
| Secret memorandum discussing the procurement and manufacturing process for the Wraith gearbox. | 28th Jan 1937 | Box 8 \ 11 11-page058 | |
| Trial of double helical gears for potential gearbox economies. | 2nd Feb 1937 | Box 8 \ 11 11-page059 | |
| Secret memo confirming the fitting of a second Wraith gearbox to vehicle 18.G.1V for dynamometer and road testing. | 2nd Feb 1937 | Box 8 \ 11 11-page060 | |
| Cost-reduction modifications for the Wraith II Gearbox. | 2nd Feb 1937 | Box 8 \ 11 11-page061 | |
| Investigation into a complaint that the Wraith II gearbox cannot be removed due to a temporary, oversized propeller shaft being fitted. | 5th Feb 1937 | Box 8 \ 11 11-page062 | |
| Modification to the Wraith II gearbox second motion shaft, referencing drawing N.Sch.5035. | 9th Feb 1937 | Box 8 \ 11 11-page063 | |
| Modifications to the Wraith II gearbox, specifically a detachable reverse gear fork. | 15th Feb 1937 | Box 8 \ 11 11-page064 | |
| Modifications to the Wraith II Gearbox, including increased clearances and the deletion of a retaining plate. | 17th Feb 1937 | Box 8 \ 11 11-page065 | |
| Suggesting the synchromesh gear actuating stirrups for the Wraith II gearbox be made from cast iron instead of mild steel. | 19th Feb 1937 | Box 8 \ 11 11-page066 | |
| With remarks on suggestions for cost reduction on the Wraith Gearbox. | 24th Feb 1937 | Box 8 \ 11 11-page067 | |
| Point-by-point response to suggestions regarding alterations for components like shafts and plungers. | 24th Feb 1937 | Box 8 \ 11 11-page068 | |
| The use of Wraith plungers on the Phantom and discussing anti-rattle control springs. | 25th Feb 1937 | Box 8 \ 11 11-page069 | |
| Modifications to the Wraith gearbox casing. | 25th Feb 1937 | Box 8 \ 11 11-page070 | |
| The failure of the Wraith II No. 1 gearbox's second motion shaft during a dynamometer test. | 3rd Mar 1937 | Box 8 \ 11 11-page071 | |
| Diagram illustrating the failure of a gearbox after a dynamometer test, showing a broken 2nd motion shaft. | 27th Feb 1937 | Box 8 \ 11 11-page072 | |
| Cost-saving modifications to the Wraith II gearbox. | 16th Mar 1937 | Box 8 \ 11 11-page073 | |
| New gearbox design for the Wraith III model, comparing it to the Wraith II. | 16th Mar 1937 | Box 8 \ 11 11-page074 | |
| Technical memorandum detailing design changes and considerations for gearbox components including oil scoops, synchromesh cones, and actuating rings. | 22th Mar 1937 | Box 8 \ 11 11-page075 | |
| Secret memo regarding a modification to the Wraith III Gearbox, specifically deleting plugs for selector rods. | 22th Mar 1937 | Box 8 \ 11 11-page076 | |
| Modifications to the Wraith III gearbox assembly. | 31th Mar 1937 | Box 8 \ 11 11-page077 | |
| Specification change for the Wraith III gearbox concerning oil holes. | 12th Apr 1937 | Box 8 \ 11 11-page078 | |
| Modifications to the Wraith III Gearbox to make gear wheel bosses flush with the rims. | 24th Apr 1937 | Box 8 \ 11 11-page079 | |
| Positioning of the reverse driving gear on the layshaft. | 6th May 1937 | Box 8 \ 11 11-page080 | |
| Modification to the Wraith III gearbox casing to facilitate the machining of bearings for the 1st speed actuating rod. | 6th May 1937 | Box 8 \ 11 11-page081 | |
| Manufacturing tolerances and material hardness for the Wraith III gearbox 2nd speed coupling. | 21th May 1937 | Box 8 \ 11 11-page082 | |
| The Wraith gearbox, discussing a trial for the toothed coupling comparing 'V' serrations with Fellows involute teeth. | 10th Jun 1937 | Box 8 \ 11 11-page083 | |
| Modification to the speedometer drive for the Wraith III gearbox, replacing an open ended bearing. | 10th Jun 1937 | Box 8 \ 11 11-page084 | |
| Modifications to the Wraith III Gearbox rocking shaft to improve the ease of forging. | 21th Jun 1937 | Box 8 \ 11 11-page085 | |
| Modification to the oil holes in the Wraith III gearbox constant mesh pinion and bush. | 24th Jun 1937 | Box 8 \ 11 11-page086 | |
| Use of a common gearbox and divided propeller shaft for Bentley, Phantom, and Wraith models. | 24th Jun 1937 | Box 8 \ 11 11-page087 | |
| Permanent design for the Wraith III gearbox rear suspension and stay. | 1st Jul 1937 | Box 8 \ 11 11-page088 | |
| Instruction to make and fit parts for the Wraith III gearbox rear suspension and stay for a 10,000-mile test in France. | 7th Jul 1937 | Box 8 \ 11 11-page089 | |
| Analysis of a spongy gear change feel on the Wraith model, proposing an increased diameter shaft to improve stiffness. | 16th Jul 1937 | Box 8 \ 11 11-page090 | |
| Request for experimental details of a new shaft for the Wraith's change speed mechanism to match the stiffness of the 25/30 HP chassis. | 30th Jul 1937 | Box 8 \ 11 11-page091 | |
| Proposed design changes to the Wraith III gearbox to simplify production. | 23th Aug 1937 | Box 8 \ 11 11-page092 | |
| Overdrive gearboxes on the Wraith model. | 9th Sep 1937 | Box 8 \ 11 11-page093 | |
| Rationale for fitting overdrive gearboxes to Phantom III and Wraith models. | 8th Sep 1937 | Box 8 \ 11 11-page094 | |
| Modifying the Wraith's change speed mechanism to a fully-isolated type to eliminate gear lever rattles. | 11th Sep 1937 | Box 8 \ 11 11-page095 | |
| Secret memorandum detailing the deletion of adjustment washers on the Wraith III gearbox. | 13th Sep 1937 | Box 8 \ 11 11-page096 | |
| Two alternative manufacturing schemes for the Wraith III gearbox distance piece. | 15th Sep 1937 | Box 8 \ 11 11-page097 | |
| The deletion of adjustment washers on the Wraith III gearbox to save assembly time. | 13th Sep 1937 | Box 8 \ 11 11-page098 | |
| The fully isolated gear lever modification for the Wraith III. | 11th Oct 1937 | Box 8 \ 11 11-page099 | |
| Modifications to gearbox bearings for the Wraith III model to facilitate diamond boring. | 29th Oct 1937 | Box 8 \ 11 11-page100 | |
| Accompanying blueprints for a modified Gearbox Oil Filler Plug for the Wraith III model. | 5th Dec 1938 | Box 8 \ 11 11-page101 | |
| New gearbox layshaft drawing (PD.82) for Bentley and Wraith models, discussing the grinding process. | 22th Dec 1937 | Box 8 \ 11 11-page102 | |
| Blueprints for the modified position of the interlocking mechanism for Wraith III gearbox selector shafts. | 24th Dec 1937 | Box 8 \ 11 11-page103 | |
| Modifications to the Rear End of the Gear Box for the Wraith III Chassis. | 30th Dec 1937 | Box 8 \ 11 11-page104 | |
| Technical note outlining two methods for implementing an overdrive in the Wraith gearbox. | 31th Dec 1937 | Box 8 \ 11 11-page105 | |
| Parts required for modifications to the Wraith III chassis gearbox and motion shafts. | 6th Jan 1938 | Box 8 \ 11 11-page106 | |
| Modifications to the Wraith III gear change mechanism. | 10th Jan 1938 | Box 8 \ 11 11-page107 | |
| Fault where the Wraith gearbox jumps out of 3rd gear and recommending the fitting of a concertina type coupling. | 12th Jan 1938 | Box 8 \ 11 11-page108 | |
| Proposal to change the orientation of the Wraith gearbox drain plugs from horizontal to vertical. | 15th Jan 1938 | Box 8 \ 11 11-page109 | |
| The Wraith III gear change mechanism, specifically scheme GCD.331. | 20th Jan 1938 | Box 8 \ 11 11-page110 | |
| Replacement of a steel thrust washer with a bronze one in the Wraith gearbox. | 22th Jan 1938 | Box 8 \ 11 11-page111 | |
| Modification to the Wraith gear box sliding piece for top and 3rd speed to prevent disengagement on over-run. | 25th Jan 1938 | Box 8 \ 11 11-page112 | |
| Requesting a new transmission shaft for the Wraith Gearbox based on a previous experiment. | 2nd Feb 1938 | Box 8 \ 11 11-page113 | |
| Urgent request for the manufacture of a specific Wraith transmission shaft. | 11th Feb 1938 | Box 8 \ 11 11-page114 | |
| The measured deflections on the Wraith gearbox transmission shaft when tightening a nut. | 11th Feb 1938 | Box 8 \ 11 11-page115 | |
| Incorrectly marked dipsticks on the Wraith gearbox and the correct oil level. | 22th Feb 1938 | Box 8 \ 11 11-page116 | |
| Request for a one-off stiffened gearbox extension shaft for a Wraith experimental car to eliminate a period. | 22th Mar 1938 | Box 8 \ 11 11-page117 | |
| Confirming a request for three more fully isolated change speed mechanisms for the Wraith III model. | 28th Mar 1938 | Box 8 \ 11 11-page118 | |
| The deletion of an oil scoop from the Wraith gear box due to assembly difficulties. | 13th Apr 1938 | Box 8 \ 11 11-page119 | |
| Covering memo for a drawing detailing a modification to the rubber buffers for the gearbox tie rod. | 20th Apr 1936 | Box 8 \ 11 11-page120 | |
| Disagreeing with the omission of the oil scoop from the Wraith gear box. | 27th Apr 1938 | Box 8 \ 11 11-page121 | |
| Impracticality of installing the B.50 gearbox into the existing Wraith III chassis. | 28th Apr 1938 | Box 8 \ 11 11-page122 | |
| Proposed omission of an oil scoop from the Wraith gearbox. | 7th May 1938 | Box 8 \ 11 11-page123 | |
| Cover note for drawing FD.174 showing overdrive ratios for the Wraith III gearbox, which was deemed unnecessary and sent for filing. | 17th May 1938 | Box 8 \ 11 11-page124 | |
| Request for a sketch and detailed drawing of the experimental Wraith change gear mechanism. | 24th Jun 1938 | Box 8 \ 11 11-page125 | |
| Request for figures regarding the efficiency of an Acme oil thread on a Wraith first motion shaft. | 28th Jun 1938 | Box 8 \ 11 11-page126 | |
| Suggested modification to the 25/30 (Wraith) gearbox synchromesh operating gear. | 27th Aug 1938 | Box 8 \ 11 11-page127 | |
| Modification to synchro-mesh operating cams for a 25/30 HP vehicle. | 22th Jun 1938 | Box 8 \ 11 11-page128 | |
| Failure of a Wraith speedometer drive due to seizure, corrosion, and lack of lubrication. | 15th Oct 1938 | Box 8 \ 11 11-page129 | |
| Modifications to a Wraith gearbox to make it suitable for use on a Bentley lll. | 9th Nov 1938 | Box 8 \ 11 11-page130 | |
| Modification to the Speedometer Drive for the Wraith model to improve lubrication. | 9th Nov 1938 | Box 8 \ 11 11-page131 | |
| Failure of a Wraith first motion shaft and the fitting of replacement parts. | 18th Nov 1938 | Box 8 \ 11 11-page132 | |
| Wraith gearbox failure at 35,000 miles and the proposed design modification. | 18th Nov 1938 | Box 8 \ 11 11-page133 | |
| Trial of a new, cost-reduced change gear shaft for the Wraith model. | 19th Nov 1938 | Box 8 \ 11 11-page134 | |
| Production change for the Wraith change gear mechanism, specifically the GW.1794 gear lever shaft. | 24th Aug 1938 | Box 8 \ 11 11-page135 | |
| | | | |
