With respect to Johnny Ringo, the 3.08 axle ratio may not be too rare. My '62 Parisienne has the original 3.08 axle installed. I looked up the specs in my '61 service manual and read that the 3.08 was the gear ratio used in combination with the 283 (2 & 4 barrel carb) and powerglide.
The 3.36 gear ratio was typical to the 348 (4 barrel & tri-power) and 283 (4 barrel) with 3-speed or turboglide transmissions.
I also seen a reference that the 3.55 was used only with the 261 6 cylinder/3 speed in wagons. Presumably for greater loading.
I suppose that over 50years, there could be exceptions as changes during service repairs or mods were done.
the axle ratio on my 62 is 3:36 so I checked the specs in my shop manual supplement for 62. This differs some from the 61 shop manual. According to the 62 specs. the 3:36 ratio was standard throughout except for the 3 speed station wagon which used the 3:55 ratio. The only place the 3:08. is listed is in the 327 4 barrel power glide column. It also states that positraction was available in ratios of 3:08, 3:36, 3:55, and 3:70. Hope this helps or does it just add to the confusion?
......I can't argue with that Lad820, I think that maybe the newer of the X frame cars would have the 3.08's , but having about 25 X-Frame cars ( 20 are 58's ) I have never seen a 3.08 rear end in a 6cyl, 283 or 348 car here. I've had 3.36 posi , and a to me surprise a 59 pontiac 6 std with a 3.55 posi.
the axle ratio on my 62 is 3:36 so I checked the specs in my shop manual supplement for 62. This differs some from the 61 shop manual. According to the 62 specs. the 3:36 ratio was standard throughout except for the 3 speed station wagon which used the 3:55 ratio. The only place the 3:08. is listed is in the 327 4 barrel power glide column. It also states that positraction was available in ratios of 3:08, 3:36, 3:55, and 3:70. Hope this helps or does it just add to the confusion?
It certainly does help. I spun one wheel and counted the shaft revolutions, and then doubled it. It usually works just fine on my non-posi diffs. I was in a hurry and it seemed to come out around 3 and a quarter, give or take a bit. I wasn't sure if that was reasonable, but I think it is. Likely it's a 3.36 ratio.
I've got the thing for sale, and sometimes people ask about the gears, so I thought I'd check. I don't feel like sliding out both axles and pulling the pumpkin just to count teeth.