just abliterated my rear axle trying to pull a sled, found out some body swaped a non-full floating 3. 90 in place and still has a 3. 54 in the front. well looking on car-parts.com at junk yards the options for a 81-93 ram are 3. 07, 3. 55, 3. 90, 4. 10, and 4. 56 but the tag says 3. 54, so is it a 3. 54 or 3. 55 or does it even matter being that close which is why i am wondering because i can get a hold of a 3. 55 full float from a e350 econoline van for free. i figure the hardest part may be just cutting and moving the perches for the springs.