172 Gearbox problem and vibration

[lukeallen]

Well i had my first race at snetterton yesterday and was running 6th overall. braked for a corner downshifted 5th to 4th nothing out of the ordinary but it woudnt go in to gear. tried all the gears and it will only go in to 5th. There was a serious vibration from the start of the race but i carried on, i have checked the gearbox mounts but they look fine. any ideas chaps? I have a video of the car with the vibration, ill get it uploaded.

 

[Scotty-boi]

Diff? Caused crazy vibrations when mine shat itself

 

[lukeallen]

Hmm i think its going to be a new gearbox/diff jobbie then!

 

[Scotty-boi]

Lol, don't take my word for it straight away. Could be something else, maybe something else in the box that is cheaper to replace than the diff,
When my diff went I did get another box and have it rebuilt though!

Is the shaking felt through the drivetrain, or throughout the whole car,
Mine was quite violent. And only shook under heavy load

 

[lukeallen]

Yeah it was fairly violent shaking the whole car. Ive just started looking over it and the drivers side cv joint is very loose. so thats for sure the cause of the vibration but im not sure how this would of affected the gearbox as the bearing before the gearbox is fine.