What do the numbers on this pinion mean?

[Dodgeboy]

This is a 2.76 ratio pinion from a 742 housing. It is getting replaced with a 4.30. I know the #s have something to do with pinion depth but I cant't make sense of them. The way I see them is a -1 on top and an 18 on bottom. What do they mean?

Thanks,

Roger

[jet-taz]

i would'nt go with those numbers for you new set.  set up your new set from the specs. from the manufacture .

[Dodgeboy]

I don't plan on using these #s for the new setup, but I sure would like to know what they mean.

Thanks,

Roger

[jet-taz]

i think the top no is the pinion dept -1.00 and the 18 is measurement of the torque to rotated the pinion 18 inch lbs

[Dodgeboy]

Thanks Jet-Taz,

Now it makes perfect sense. I knew what the -1 meant but I couldn't figure out the 18.

The gear I am installing is a Richmond and it is marked with 2.731. Anyone know how far this deviates from the ideal or nominal checking distance?

Since my bearings and cones are in good condition I plan on reusing them. If I knew what the ideal checking distance was some simple math would tell me what thickness pinion shim to use.

Thanks

[383man]

It is the variance in the machining of the pinion.   When you use a pinion depth tool and you get the shim size the pinion depth you add or subtract that # to the shim size.  Most pinion #'s are something like    ( -1 )   or  ( +2 )  or about that.  They also have another # on it sometimes and it makes it hard to read the # you need for the pinion depth variance.   Yours looks like ( -1 ) to me.   Ron