So what are the real differences in the newer "metric" Dana 60's & the older ones? I re-did the cover on my '01 Dodge rear 60 because it was leaking & noticed an odd "tone ring"(?) under the ring gear (for ABS?) & it just looks "different" in there. Do these newer ones & their components interchange with the ones from the '70's & '80's? Is the only difference that they list the ring diameter in metric units or??????

Thanx!