Speedometer Gear

Can anybody tell me why I keep breaking a speedomter drive gear (2 in 500 miles). Running a th-400 behind a 450hp small block.

 

Is the gear on the output shaft in the correct place ??

This is a photo of a 700R4 speedometer setup but a Turbo 400 has the same basic setup.
Is the green gear in the correct place ??




The right bullet is also required ... and be all the way IN.



There are two different ones ...

One for the 34 to 39 gear and one for the 40 to 45 gear.

I actually like to use a metal gear ( instead of the green plastic ) but they are only available in a 15 and a 17.

 

How do you replace the (green) gear on the output shaft? Remove the nose cone?

 

thanks, and yes everything is in the right place. Its a hughes built 400 and electronic stewart warner guage. also have an orange drive and a brown 39 tooth driven. I will try a different lube in housing.

 

Remove the tailhousing ...



The stell gears ( 15 tooth and 17 tooth ) have to be pulled off with a puller. The Plastic ones are held on the shaft with a little clip. Remove the clip and the gear should slide off. SOMETIN+MES they require a little tapping action