Changi558

Hey guys,

So I have a 1991 Nissan 1via with an RB25DET engine swap (believe it's a series 1 RB25det). I've been trying to get the speedo in the dash working. I've put two rb25det speed sensors in the gearbox now and both times it's been getting chewed out in a concave shape centrally on the sensor gear.

The only reason I can think of the reason is that the gear box I have either isnt an RB25det gearbox, it is a different RB gearbox from a different car, or is there a difference in an RB25 series 1 and 2 gearbox that might be the cause of my sensor gear getting chewed up.

Is there a way to identify the different types of RB gearboxes from the outside with cracking them open?

Any help or advice is appreciated!