#7898, "RE: how can you tell the difference between a 3.55 & 3.94 differential" In response to In response to 5
Ok,
Answering your question Mikey, the 3.55 and 3.94 ring gear both have the same amount of teeth (71). The notches that you are asking ARE on the 3.94 ring gear.
The 3.55 ring gear is about 1/8-1/16 of an inch smaller than the one on the 3.94.
If you put them both side by side, you should be able to see which one is smaller.