3:54 definitely was the standard gear as Longhorn man stated. Come to think of it I have never owned a single 67-72 two wheel drive that didn’t have 3:54 gears… Here is a few of the junk I have owned or still own.
1968 GMC C1500 305 V6/SM435 Dana 44 3:54 (parted). This truck’s rear axle is temporarily in my other ’68 GMC when the Dana 60 broke.
1968 GMC C1500 396BB/TH400 Dana 60(semi-floater: Rare) 3:54 (still have) Still have the broken semi-float Dana 60 as well. Something about those hard 1-2 TH400 shifts will a full race shift kit that tends to knock teeth off ring gears
1970 Chevy C10 402BB/SM465 Dana 44 3:54 (sold)
1972 Chevy C20 350/TH350 Eaton not sure of the gear ratio but the highway RPM’s are consistent of 3:54 (still have). I’ll have to chisel off the axle grime and look for a tag someday.
1972 K5 Blazer 3:73....4x4's were a different ball of gear wax anyway.