| Description | Date | Identifier | |
| Proposals for the New Departure bearing and oil retaining devices on the 1' offset hypoid rear axle. | 2nd Feb 1928 | Box 136 \ 5 scan0156 | |
| Pinion, bearing, and oil retaining for a 1' offset hypoid gear. | 3rd May 1928 | Box 136 \ 5 scan0157 | |
| Debit from Springfield for special Hypoid Gears and requesting comments before payment. | 7th Mar 1928 | Box 136 \ 5 scan0158 | |
| The final revision of a thrust bearing for an 'SS' 1' offset hypoid pinion. | 10th Mar 1928 | Box 136 \ 5 scan0159 | |
| Invoice from the Gleason Co. for 3 pairs of special Hypoid Gears ordered for experimental purposes. | 12th Mar 1928 | Box 136 \ 5 scan0160 | |
| The payment for three hypoid gears ordered from the Gleason Company. | 14th Mar 1928 | Box 136 \ 5 scan0161 | |
| Frame height modifications, including front axle changes and the potential use of hypoid gears. | 1st Jun 1928 | Box 136 \ 5 scan0162 | |
| The satisfactory performance of a hypoid rear axle and an investigation into wing clearance issues. | 7th Jun 1928 | Box 136 \ 5 scan0163 | |
| Modifications and ratios of rear axle hypoid bevel gears. | 14th Jun 1928 | Box 136 \ 5 scan0164 | |
| Letter to C.C. Wakefield Ltd. regarding experiments with Hypoid bevel gears and the required special oil. | 27th Jun 1928 | Box 136 \ 5 scan0165 | |
| Letter from C.C. Wakefield & Co. acknowledging correspondence and promising to follow up with The Gleason Co. and their agents. | 28th Jun 1928 | Box 136 \ 5 scan0166 | |
| Alterations to a car, including fitting a Hypoid rear axle, and arrangements for its testing and investigating a separate vehicle's vibration issue. | 28th Jun 1928 | Box 136 \ 5 scan0167 | |
| Cancellation of an order for three pairs of Gleason Hypoid Bevel Gears. | 2nd Oct 1928 | Box 136 \ 5 scan0168 | |
| Alterations to the rear hub and brake drum for the 'India 4' rear axle to accommodate rebuilt wire wheels. | 7th Nov 1923 | Box 136 \ 5 scan0169 | |
| Use of standard English oil, specifically Castrol 'R', for hypoid gears. | 20th Nov 1928 | Box 136 \ 5 scan0170 | |
| 'Hs.' to 'Mr. Alvey O.O.' requesting an order for 2 gallons of Whitmores No.O oil. | 21th Nov 1928 | Box 136 \ 5 scan0171 | |
| Contingency plans for potential machinery delivery delays from Gleason's for the production of hypoid gears. | 27th Nov 1928 | Box 136 \ 5 scan0172 | |
| Communication confirming a satisfactory delivery schedule for six sets of hypoid gears. | 20th Dec 1928 | Box 136 \ 5 scan0173 | |
| Delayed shipment of six sets of 40/50 HP Hypoid Gears arriving on the 'AMERICAN MERCHANT'. | 18th Jan 1929 | Box 136 \ 5 scan0174 | |
| Transportation of six sets of 40/50 HP Hypoid Gears from the 'AMERICAN MERCHANT' ship. | 22th Jan 1929 | Box 136 \ 5 scan0175 | |
| Request to increase an order for hypoid gear forged blanks from 200 pairs to 250 sets. | 22th Jan 1929 | Box 136 \ 5 scan0176 | |
| Secret report on dynamometer tests of Hypoid gears on an 'SS' chassis. | 1st Feb 1929 | Box 136 \ 5 scan0177 | |
| Issues with joints, gearbox performance, and petrol consumption during vehicle testing. | 1st Feb 1929 | Box 136 \ 5 scan0178 | |
| SS and Phantom power curve comparisons, dynamometer figures, and the fitting of a new dummy hub type rear wheel carrier. | 7th Feb 1929 | Box 136 \ 5 scan0179 | |
| Graph plotting Horse Power at the road wheels against Engine RPM for Phantom and S.S. chassis models. | 7th Feb 1929 | Box 136 \ 5 scan0180 | |
| Comparison of different types of trunnion bearings. | 8th Feb 1928 | Box 136 \ 5 scan0181 | |
| Modifications to improve oil supply to the rear axle hypoid pinion thrust bearings. | 20th Feb 1929 | Box 136 \ 5 scan0182 | |
| Modifications to a hypoid rear axle casing to overcome distortion from a full throttle test. | 19th Mar 1929 | Box 136 \ 5 scan0183 | |
| Go-ahead for experimental parts and an urgent request to lower a car's rear floor. | 13th Apr 1929 | Box 136 \ 5 scan0184 | |
| Secret memorandum discussing weight reduction and performance improvements for the future 20 HP model. | 16th Apr 1929 | Box 136 \ 5 scan0185 | |
| Design of a hypoid rear axle casing for a 20 HP model. | 29th May 1929 | Box 136 \ 5 scan0186 | |
| Notice specifying Whitmore's compound No. 'O' as the correct lubricant for Hypoid bevel gears. | 19th Jun 1929 | Box 136 \ 5 scan0187 | |
| Reduction of the offset on the 'Japan' hypoid rear axle and correcting a naming error on a scheme. | 28th Jun 1929 | Box 136 \ 5 scan0188 | |
| Proposal to test Castrol 'R' oil in 40/50 HP Chassis hypoid axles instead of Whitmore's compound. | 5th Jul 1929 | Box 136 \ 5 scan0189 | |
| Type of oil for lubricating hypoid axles before vehicle despatch. | 9th Jul 1929 | Box 136 \ 5 scan0190 | |
| Letter to C.C. Wakefield & Co. regarding the unsatisfactory performance of Castrol 'R' oil in Hypoid rear axles compared to Whitmore's oil. | 19th Jul 1929 | Box 136 \ 5 scan0191 | |
| Directive on the mandatory use of Whitmores Compound for lubricating hypoid axles during the running-in period. | 30th Jul 1929 | Box 136 \ 5 scan0192 | |
| Failed test of an alternative gear oil for a Hypoid Axle. | 22th Aug 1929 | Box 136 \ 5 scan0193 | |
| Failure of hypoid axle gears and the proposed testing of a new castor oil-based gear oil. | 5th Sep 1929 | Box 136 \ 5 scan0194 | |
| Letter to Gleasons Works in the USA regarding the testing of a newly developed oil for hypoid gears. | 6th Sep 1929 | Box 136 \ 5 scan0195 | |
| Confirming that 2 gallons of special lubricant are being sent for testing on a hypoid axle. | 17th Sep 1929 | Box 136 \ 5 scan0196 | |
| Revision to the Sports Phantom II rear axle, with modifications to strengthen the hypoid axle casing. | 23th Oct 1929 | Box 136 \ 5 scan0197 | |
| The decision on hypoid gears for the Sports Phantom rear axle. | 25th Oct 1929 | Box 136 \ 5 scan0198 | |
| Sending a drawing of a standard 11/41 hypoid rear axle for record-keeping purposes. | 26th Oct 1929 | Box 136 \ 5 scan0199 | |
| Back axle and gear requirements for the Phantom II Sports Car. | 26th Oct 1929 | Box 136 \ 5 scan0200 | |
| Progress on development projects codenamed 'China' and 'Japan', detailing cylinder heads, manifolds, and a hypoid axle. | 11th Nov 1929 | Box 136 \ 5 scan0201 | |
| Development challenges and production delays for the 20 HP. Hypoid Axle. | 13th Nov 1929 | Box 136 \ 5 scan0202 | |
| Agreeing to make a subframe for a Park Ward Twenty limousine to suit a hypoid axle, with details on the required modifications. | 3rd Dec 1929 | Box 136 \ 5 scan0203 | |
| Letter from the Vacuum Oil Company concerning the lubrication of rear axle hypoid gears and the provision of a sample for testing. | 4th Dec 1929 | Box 136 \ 5 scan0204 | |
| Screwed backing nut for the Phantom II hypoid pinion thrust bearing. | 5th Dec 1929 | Box 136 \ 5 scan0205 | |
| Proposing a testing protocol for a new Hypoid rear axle fitted to a 20 HP car before its standardisation. | 16th Dec 1929 | Box 136 \ 5 scan0206 | |
| Proposed testing of a hypoid rear axle for a 20 HP car. | 18th Dec 1929 | Box 136 \ 5 scan0207 | |
| Testing procedures and standardization for the Hypoid Rear Axle 20/25 HP | 19th Dec 1929 | Box 136 \ 5 scan0208 | |
| Letter concerning oil deterioration and gear wear in a Hypoid rear axle. | 19th Dec 1929 | Box 136 \ 5 scan0209 | |
| Letter from a supplier, Buck & Hickman Ltd., responding to a complaint about a product, likely a lubricant for hypoid gears. | 23th Dec 1929 | Box 136 \ 5 scan0210 | |
| Chasing progress on finding alternative oils to Whitmore's Compound for Hypoid Axles. | 30th Dec 1929 | Box 136 \ 5 scan0211 | |
| Testing of various oils for hypoid axles. | 30th Dec 1929 | Box 136 \ 5 scan0212 | |
| The results of a 3,000-mile road test using ordinary oil versus Whitmore's oil on a dynamometer. | 3rd Jan 1930 | Box 136 \ 5 scan0213 | |
| Micro-examination report on a failed hypoid gear from an axle. | 3rd Jan 1930 | Box 136 \ 5 scan0214 | |
| Letter to Messrs. C.C. Wakefield & Co. Ltd. requesting a sample of aged axle oil for further testing. | 13th Jan 1930 | Box 136 \ 5 scan0215 | |
| Comparative laboratory tests on oils for hypoid rear axles. | 16th Jan 1930 | Box 136 \ 5 scan0216 | |
| Enabling the withdrawal of the 20HP hypoid rear axle pinion for inspection. | 21th Jan 1930 | Box 136 \ 5 scan0217 | |
| Oil for hypoid rear axles and investigating gear trouble on a Phantom I car from the London Trials. | 28th Jan 1930 | Box 136 \ 5 scan0218 | |
| Failure of hypoid rear axle gears due to insufficient oil. | 28th Jan 1930 | Box 136 \ 5 scan0219 | |
| Causes of tooth-surface breakdown in hypoid rear axles, suspecting cavitation in cold weather. | 29th Jan 1930 | Box 136 \ 5 scan0220 | |
| Potential replacement of Whitmore's Compound with a lubricant from Messrs. Price for rear axle lubrication. | 31th Jan 1930 | Box 136 \ 5 scan0221 | |
| The ordering and availability of hypoid gears for 20 HP and 40/50 HP chassis. | 31th Jan 1930 | Box 136 \ 5 scan0222 | |
| On the testing and proposed standardisation of Price's Hypoid axle oil. | 4th Feb 1930 | Box 136 \ 5 scan0223 | |
| Letter from Vacuum Oil Company, Ltd. arranging an engineer's visit to Derby. | 15th Feb 1930 | Box 136 \ 5 scan0224 | |
| Standardisation of an alternative gear compound oil for Phantom II Hypoid Rear Axles. | 17th Feb 1930 | Box 136 \ 5 scan0225 | |
| Testing and performance of alternative gear oils for hypoid rear axle gears. | 14th Feb 1930 | Box 136 \ 5 scan0226 | |
| Compatibility of mixing different lubricant compounds for axles. | 18th Feb 1930 | Box 136 \ 5 scan0227 | |
| Request for urgent tests regarding a price alternative to Whitmore's Compound. | 19th Feb 1930 | Box 136 \ 5 scan0228 | |
| Dynamometer testing of Phantom II hypoid rear axles with an alternative compound gear oil. | 21th Feb 1930 | Box 136 \ 5 scan0229 | |
| Pinion bearing issue on a hypoid axle during a 20 HP 10,000 miles test. | 1st Mar 1930 | Box 136 \ 5 scan0230 | |
| Trouble with the pinion bearing on the hypoid axle during a 20 HP 10,000-mile test. | 3rd Mar 1930 | Box 136 \ 5 scan0231 | |
| Compatibility and testing of different Hypoid Axle Oils. | 3rd Mar 1930 | Box 136 \ 5 scan0232 | |
| Hypoid axle failure during a 20 HP 10,000 miles test. | 4th Mar 1930 | Box 136 \ 5 scan0233 | |
| Hypoid axle and exhaust system failures during a 25 HP car's 10,000-mile test in France. | 14th Mar 1930 | Box 136 \ 5 scan0234 | |
| Modifications after failures, sending new parts to France for extended testing, and arranging official reports. | 14th Mar 1930 | Box 136 \ 5 scan0235 | |
| Supply of cheaper and simpler hypoid axle oils. | 14th Mar 1930 | Box 136 \ 5 scan0236 | |
| Laboratory report comparing the properties and carrying out ageing tests on three different lubricating compounds for a hypoid axle. | 24th Mar 1930 | Box 136 \ 5 scan0237 | |
| Design committee report on the 10,000-mile test of model 14-G4, discussing modifications to the exhaust pipes and issues with exhaust valves and the rear axle. | 1st Apr 1930 | Box 136 \ 5 scan0238 | |
| Cover note for a letter from Gleason Works listing oils that passed tests for Hypoid axles, with a suggestion to test one on aero engine gears. | 4th Apr 1930 | Box 136 \ 5 scan0239 | |
| Letter from Gleason Works enclosing a list of oils which have passed tests with their specifications. | 20th Mar 1930 | Box 136 \ 5 scan0240 | |
| List of lubricants that passed a mechanical running test of a hypoid geared axle. | 18th Mar 1930 | Box 136 \ 5 scan0241 | |
| Continued list of test conditions, detailing load application, pressure, and the use of a cooling fan. | 4th Apr 1930 | Box 136 \ 5 scan0242 | |
| Development and testing of alternative oils for hypoid axles. | 4th Apr 1930 | Box 136 \ 5 scan0243 | |
| Letter to C.C. Wakefield & Co. Ltd. requesting the address of their New York representative for an oil supply. | 4th Apr 1930 | Box 136 \ 5 scan0244 | |
| Strategy for gathering information on hypoid rear axle failures from customers. | 15th Apr 1930 | Box 136 \ 5 scan0245 | |
| Arranging a meeting with Capt. Malcolm Campbell regarding the failure of hypoid rear axles. | 17th Apr 1930 | Box 136 \ 5 scan0246 | |
| Dynamometer tests of a hypoid rear axle to induce failure under extreme conditions. | 1st Apr 1930 | Box 136 \ 5 scan0247 | |
| Axle oil levels, oil types, and investigations into pinion tooth failures. | 29th Apr 1930 | Box 136 \ 5 scan0248 | |
| Verification of oil level in the rear axle of several Phantom II chassis. | 29th Apr 1930 | Box 136 \ 5 scan0249 | |
| Rear axle failures on dynamometer tests due to the type of lubricant being used. | 29th Apr 1930 | Box 136 \ 5 scan0250 | |
| Ongoing investigation into rear axle failures, specifically concerning Hypoid gears and testing methods. | 9th May 1930 | Box 136 \ 5 scan0251 | |
| Gleason's hypoid axle and the metallurgy of gear sets. | 9th May 1930 | Box 136 \ 5 scan0252 | |
| Fault and proposed modification to the 20/25 HP Hypoid Rear Axle. | 7th May 1930 | Box 136 \ 5 scan0253 | |
| Request to manufacture two experimental nitralloy steel wheels for a Hypoid axle, noting a warning about their performance. | 12th May 1930 | Box 136 \ 5 scan0254 | |
| Recommending the laboratory examination of failed gears from a hypoid back axle. | 28th May 1930 | Box 136 \ 5 scan0255 | |
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