| Description | Date | Identifier | |
| Opinions and design considerations for a 'Double Top Gear' system. | 7th Apr 1931 | Box 15 \ 5 Scan205 | |
| Brief typed note regarding the functionality of plain jaws and potential gear issues. | 28th May 1931 | Box 15 \ 5 Scan206 | |
| 45HP double top gearbox conversion to an electrically controlled friction type. | 28th May 1931 | Box 15 \ 5 Scan207 | |
| Design and development of 25HP and 45HP car gearboxes. | 2nd Jun 1931 | Box 15 \ 5 Scan208 | |
| Proposed modification to the P.2. Epicyclic 3rd Speed Gearbox. | 4th Jul 1931 | Box 15 \ 5 Scan209 | |
| New filling plug and level stick design for the J.4 gearbox and its potential adaptation. | 14th Jul 1931 | Box 15 \ 5 Scan210 | |
| The J.4 gearbox, detailing a new filling plug, level stick, and cover modification. | 14th Jul 1931 | Box 15 \ 5 Scan211 | |
| Correspondence regarding modifications to a universal joint flange, sheet metal baffle, and cross-member packing. | 23th Jul 1931 | Box 15 \ 5 Scan212 | |
| Requesting sketches and design information for radiator mounting, lubrication systems, and the speedometer drive. | 17th Aug 1931 | Box 15 \ 5 Scan213 | |
| Tests completed on a speedometer drive, specifically concerning slots in the faces of bushes. | 31th Aug 1931 | Box 15 \ 5 Scan214 | |
| Development and implementation of 'easy change' synchro-mesh gearboxes for the 25 HP and Phantom II models. | 20th Oct 1931 | Box 15 \ 5 Scan215 | |
| Expressing concern over gearbox development for the Phantom II, suggesting scaling up the 20/25 HP gearbox as an interim solution. | 20th Oct 1931 | Box 15 \ 5 Scan216 | |
| Requested modification and test for the P. 2 gearbox sliding gears. | 31th Oct 1931 | Box 15 \ 5 Scan217 | |
| The design of a P. 2. gearbox, specifically concerning the reverse gear mechanism and synchromesh. | 7th Nov 1931 | Box 15 \ 5 Scan218 | |
| Layout for the P. 2. Synchro Mesh Gearbox. | 13th Nov 1931 | Box 15 \ 5 Scan219 | |
| Query regarding the progress of modifications to the epicyclic gearbox on car 27-EX. | 20th Nov 1931 | Box 15 \ 5 Scan220 | |
| Sending scheme 3378 for the synchromesh gearbox actuating gear. | 26th Nov 1931 | Box 15 \ 5 Scan221 | |
| Lubrication of the reverse shaft on a synchro-mesh gearbox. | 1st Dec 1931 | Box 15 \ 5 Scan222 | |
| New method for lubricating the reverse shaft on all synchromesh gearboxes. | 1st Dec 1931 | Box 15 \ 5 Scan223 | |
| Change gear lever, speedometer drive, and lubrication of the thrust bearing. | 14th Dec 1931 | Box 15 \ 5 Scan224 | |
| Modifications to a P.2. synchro mesh gearbox and clutch servo damper. | 8th Dec 1931 | Box 15 \ 5 Scan225 | |
| Modifications to the side lever positions for a synchro mesh gearbox. | 14th Dec 1931 | Box 15 \ 5 Scan226 | |
| Methods for achieving silent gearboxes, including gear design and bearing types. | 4th Jan 1932 | Box 15 \ 5 Scan227 | |
| Trial of Vauxhall Cadet and Series 80 models, comparing their synchro-mesh gearboxes and engine mountings. | 6th Jan 1932 | Box 15 \ 5 Scan228 | |
| 25HP Synchro Mesh Helical 3rd Gearbox, focusing on noise, bearing arrangements, and reverse gear improvements. | 9th Jan 1932 | Box 15 \ 5 Scan229 | |
| The testing of a P.2 gearbox with an Epicyclic third gear in a 27-EX car. | 8th Jan 1932 | Box 15 \ 5 Scan230 | |
| Progress on improvements to the 25 HP Synchro-Mesh Gearbox, including noise reduction and testing of modifications. | 8th Jan 1932 | Box 15 \ 5 Scan231 | |
| On the automatic brake adjustment for an epicyclic third-speed gearbox. | 1st Jan 1932 | Box 15 \ 5 Scan232 | |
| The wear of different brake lining materials (Cotton Duck vs. Ferodo) in a P.2 gearbox with an epicyclic third. | 19th Jan 1932 | Box 15 \ 5 Scan233 | |
| Issues with the Phantom 11 gearbox, specifically the brake lining and clutch, and proposing new gear train designs. | 23th Jan 1932 | Box 15 \ 5 Scan234 | |
| Gearbox and braking system designs, comparing different configurations and mentioning sending drawings. | 23th Jan 1914 | Box 15 \ 5 Scan235 | |
| Gearbox ratio data for the Standard Phantom II. | 23th Jan 1914 | Box 15 \ 5 Scan236 | |
| Specification sheet for the Phantom II epicyclic gearbox detailing various gear ratios. | 29th Jan 1932 | Box 15 \ 5 Scan237 | |
| Suggestions for modifications and improvements to the epicyclic 3rd speed gearbox. | 29th Jan 1932 | Box 15 \ 5 Scan238 | |
| Modifications for brake lever inspection and a scheme for gear pre-selection. | 12th Feb 1932 | Box 15 \ 5 Scan239 | |
| Specifications for increased strength clutch and brake springs for an epicyclic 3rd speed gearbox. | 12th Feb 1932 | Box 15 \ 5 Scan240 | |
| Scheme 3417, which details applying a supplementary valve to the oil relay system of an epicyclic 3rd speed gearbox. | 4th Feb 1932 | Box 15 \ 5 Scan241 | |
| Comparing the gear change performance of a synchro-mesh gearbox versus a gearbox with an epicyclic third gear. | 12th Feb 1932 | Box 15 \ 5 Scan242 | |
| Future gearbox improvements, including the application of synchro-mesh and helical gears. | 27th Feb 1932 | Box 15 \ 5 Scan243 | |
| Completion and satisfactory test rig results for the new Phantom II Synchro Mesh Gearbox. | 2nd Mar 1932 | Box 15 \ 5 Scan244 | |
| Testing and proposed standardization of the Phantom II Synchro Mesh Box. | 2nd Mar 1932 | Box 15 \ 5 Scan245 | |
| Recommendation to apply synchro mesh to the second speed on gearboxes. | 2nd Mar 1932 | Box 15 \ 5 Scan246 | |
| The testing of a Phantom II Synchro Mesh Box on experimental vehicles. | 3rd Mar 1932 | Box 15 \ 5 Scan247 | |
| Road test report for the Phantom II Synchro Mesh Gearbox. | 3rd Mar 1932 | Box 15 \ 5 Scan248 | |
| Technical memorandum discussing future possibilities for a silent, easy-change gearbox. | 3rd Mar 1932 | Box 15 \ 5 Scan249 | |
| Schematic diagrams of two proposed gearbox designs, one with gear ratios and selector positions. | 7th Mar 1932 | Box 15 \ 5 Scan250 | |
| Blank document with a 'Print Room' date stamp. | 7th Mar 1932 | Box 15 \ 5 Scan251 | |
| The test schedule for the P.2 Synchro Mesh Box and the preparation of a second unit. | 4th Mar 1932 | Box 15 \ 5 Scan252 | |
| Trial of new cone and cam angles for the Phantom II Synchromesh to improve gear changing. | 11th Mar 1932 | Box 15 \ 5 Scan253 | |
| Fault with a synchro mesh gearbox after a 400-mile road test. | 14th Mar 1932 | Box 15 \ 5 Scan254 | |
| Dynamometer and road test of a Phantom II Synchromesh gearbox. | 17th Mar 1932 | Box 15 \ 5 Scan255 | |
| On-road testing of a P.2. synchro-mesh gearbox for the Phantom II. | 23th Mar 1932 | Box 15 \ 5 Scan256 | |
| Unsatisfactory performance and ongoing modifications to the P.2 synchro mesh gearbox. | 2nd Apr 1932 | Box 15 \ 5 Scan257 | |
| Request to manufacture two new cams based on an accompanying sketch for a Phantom II Synchromesh system. | 6th Apr 1932 | Box 15 \ 5 Scan258 | |
| Blueprint of a 30° Cam for a PII Synchromesh mechanism. | 31th Jan 1932 | Box 15 \ 5 Scan259 | |
| Stamped by the Print Room in Derby. | 5th Apr 1932 | Box 15 \ 5 Scan260 | |
| Held-up instructions from the drawing office for Synchro-mesh Gear Box and other parts for the 'N' and 'U' series chassis. | 12th Apr 1932 | Box 15 \ 5 Scan261 | |
| Recommendation to increase the length of slots in the Phantom II synchromesh outer member G.79872. | 13th Apr 1932 | Box 15 \ 5 Scan262 | |
| Competitive need for a synchromesh gearbox with easy change on all gears. | 19th Apr 1932 | Box 15 \ 5 Scan263 | |
| Criticism of the synchro-mesh gearbox, specifically the difficulty of engaging first gear while the car is moving. | 20th Apr 1932 | Box 15 \ 5 Scan264 | |
| Hydraulic control for an epicyclic change gear with friction brakes to improve passenger comfort. | 26th Feb 1932 | Box 15 \ 5 Scan265 | |
| Relative merits of synchromesh and epicyclic gear systems. | 26th Feb 1932 | Box 15 \ 5 Scan266 | |
| Explaining the cause of sticking top gear cones and a temporary solution. | 25th Apr 1932 | Box 15 \ 5 Scan267 | |
| Technical memo discussing synchromesh and gear changing difficulties in a gearbox. | 25th Apr 1932 | Box 15 \ 5 Scan268 | |
| Troubleshooting issues with gearbox synchronisation, gear crashing, and sticking cones. | 25th Apr 1932 | Box 15 \ 5 Scan269 | |
| Importance of a quiet gear change from second to first, and the decision not to proceed with the current synchromesh arrangement on new models. | 1st Apr 1932 | Box 15 \ 5 Scan270 | |
| Requesting modifications to drawings for the Phantom II synchromesh gearbox. | 30th Apr 1932 | Box 15 \ 5 Scan271 | |
| Design of a reverse pinion for gearboxes, including diagrams and gear ratio considerations. | 5th May 1932 | Box 15 \ 5 Scan272 | |
| Telegram feedback on synchromesh, gearboxes, and servo mechanisms. | 5th May 1932 | Box 15 \ 5 Scan273 | |
| Servo application, a telegram about transmission vibration, and arranging a telephone call. | 2nd May 1938 | Box 15 \ 5 Scan274 | |
| Potential gearbox modifications, including reverse gear, synchromesh functionality, and competitor analysis. | 4th May 1932 | Box 15 \ 5 Scan275 | |
| Design changes and departures from an original sketch for an automatic damper control system on a P.2. S.M. gearbox. | 5th May 1932 | Box 15 \ 5 Scan276 | |
| Modifications to a governor sleeve, an alternative method for oil retention, and adjustments to the handbrake and speedometer drive case. | 6th May 1932 | Box 15 \ 5 Scan277 | |
| Addition of an air release hole to the synchromesh 3rd and 4th sliding piece. | 6th May 1932 | Box 15 \ 5 Scan278 | |
| Telegram about the operation of synchromesh and clutch brakes in 20/25 and 40/50 gearboxes. | 6th May 1932 | Box 15 \ 5 Scan279 | |
| Report investigating gear change resistance and oil friction on the Phantom II synchromesh gearbox. | 7th May 1932 | Box 15 \ 5 Scan280 | |
| Testing stronger plunger springs and alternative synchronizer modifications for gear changes. | 1st May 1932 | Box 15 \ 5 Scan281 | |
| Graph showing power losses due to 1st and 2nd motion shafts for a PII Synchromesh gearbox under different oil conditions. | 7th May 1932 | Box 15 \ 5 Scan282 | |
| Blank page with a Print Room stamp from Derby. | 7th May 1932 | Box 15 \ 5 Scan283 | |
| Graph of power losses versus RPM for the 20/25 Synchromesh 1st and 2nd motion shafts under different oil conditions. | 7th May 1932 | Box 15 \ 5 Scan284 | |
| From the print room with a date stamp from Derby. | 7th May 1932 | Box 15 \ 5 Scan285 | |
| Performance and development of the synchro-mesh gearbox. | 7th May 1932 | Box 15 \ 5 Scan286 | |
| Proposal to remove the clutch brake on the Phantom II model when using synchromesh, similar to the 20/25 model. | 7th May 1932 | Box 15 \ 5 Scan287 | |
| Arrangement and detail drawings for a method of using rubber synchromesh plungers for the Phantom II Synchromesh. | 9th May 1932 | Box 15 \ 5 Scan288 | |
| Blueprint showing two views of a mechanical component with a roller and dimensional annotations. | 9th May 1932 | Box 15 \ 5 Scan289 | |
| Page stamped by the Print Room in Derby. | 9th May 1932 | Box 15 \ 5 Scan290 | |
| Blueprint drawing of a plunger component. | 9th May 1932 | Box 15 \ 5 Scan291 | |
| Blueprint drawings for a Roller and a Roller Pin. | 9th May 1932 | Box 15 \ 5 Scan292 | |
| The reverse side of a document showing a 'Print Room' stamp. | 9th May 1932 | Box 15 \ 5 Scan293 | |
| Synchromesh Gearbox issue regarding insufficient clearances on the driving dogs. | 9th May 1932 | Box 15 \ 5 Scan294 | |
| Necessity of retaining the clutch brake on the Phantom II model despite the introduction of synchromesh. | 11th May 1932 | Box 15 \ 5 Scan295 | |
| Addition of a clutch brake to the synchro-mesh gearbox. | 11th May 1932 | Box 15 \ 5 Scan296 | |
| Reverse pinions and jaw clutches in gearboxes, including a design suggestion with a diagram. | 20th May 1932 | Box 15 \ 5 Scan297 | |
| Method for testing synchromesh on the second gear in a Ph.II gearbox. | 13th May 1932 | Box 15 \ 5 Scan298 | |
| Necessity of a clutch brake with a synchromesh gearbox following a trial. | 20th May 1932 | Box 15 \ 5 Scan299 | |
| Requesting the preparation of synchromesh parts and a new type of third motion shaft. | 23th May 1932 | Box 15 \ 5 Scan300 | |
| Decision not to fit a clutch brake on the Phantom II model with a synchromesh gearbox. | 23th May 1932 | Box 15 \ 5 Scan301 | |
| Technical report on synchromesh gearbox issues, focusing on top and 3rd gear engagement, and experiments with cone angles. | 3rd May 1932 | Box 15 \ 5 Scan302 | |
| Tests and proposed modifications to a Phantom II synchromesh gearbox's first gear to prevent over-meshing. | 23th May 1932 | Box 15 \ 5 Scan303 | |
| Gearbox sideshaft failure on a 25-EX left-hand chassis. | 24th May 1932 | Box 15 \ 5 Scan304 | |
| | | | |
