Originally Posted by iceman1947
How about a 1999 Sahara?
The 99 is the split year. It can have either the 78 or 82 mm versions and it's too bad the manufactures use the overall height dimension which can easily confuse folks.
Here is the only correct way to measure the rotors for the TJ front applications.
That number won't correspond to the 78 or 82mm meaurements but you will be able to identify the rotor correctly with the measurement you get.
If the measurement is 2.75" like the picture or 70mm, you have the later 2000 and up rotor.
If the measurement is 3.00" or 76mm, then you have the earlier 97-mid 99 rotor.
The reason the dimension is so confusing is if you have the earlier and taller composite rotors on a 99 and measure the overall height, it's really close to the same height as the later and shorter full cast rotor due to how thin the rotor hat is.
Since the only dimension between the two rotors that matters is how deep it is because the unitbearings are different heights, they need to be measured like the picture.