Jaguar Repair: Jaguar XKE gearbox, jaguar xke, thrust washers

Question
Thanks for the help with the Spitfire brakes, took a ride last night and things are working as they should.
Do you have experience with Jaguar Transmission? I have a '63 E type coupe with the original Jaguar gearbox. Its got the non-sychro 1st gear. My problem is in first gear I get the characteristic whine from the straightcut gears, but on top of that I get a periodic bang, as if its missing a few teeth. I opened the box and ran the car with the wheels off in first gear, the bang seems to be from excessive endplay on one of the shafts, it sort of pulls forward while the gears are turning, and then releases, when it does that the shaft bangs against the rear of the box. I put up with it last summer, having plenty of other things on my todo list. Plan for this winter is to pull the motor and box and fix the ailment. Have you ever heard of something like this? Does it make sense that excessive endplay in the gearbox would cause such a problem? I would think the problem is more likely a bearing, causing the shafts to angularly misalign, allowing a thrust load on the shafts.

Answer
Hi Jeff,
The gearbox should not enough end play in the mainshaft gears to cause a noise when accelerating and decelerating. If you note an excess end play then something is badly worn or the nut on the rear end of the mainshaft is loose. To check it you must remove the driveshaft “U” joint flange to access the nut. How much end play do you see????

The layshaft is also subject to end play movement if the thrust washers are worn or the wrong washers were installed.
Howard