Standard Gear Ratio 1972 3/4 ton 350 V8 Suburban

[Mike C]

I have a 2x4 3/4 ton '72 Sub I bought back in '97 for parts and the drivetrain. It is a 350 TH350 and has an Eaton rear.

I know the standared 3/4 ton pickups with 6 cylinders or small V8 came with 4.56 gears and the big block trucks were 3.54 geared Dana 60's and that 1/2 ton 350 Blazers/Jimmys came with 3.07 gears and the 307 trucks were 3.73.

My question is for the Sub, what gears would have come in it standard? The SPID shows no optional diff info so I am assuming it is whatever it shipped with. It seems to me that if it had 3.54 or 4.10 it would have come with the Dana 60?

I have seen 4.57 trucks that had the 60 and others that had the Eaton. What do the experts here think my diff ratio is? (I drove it 250 miles after I bought it with 235 85 16's on it so my "butt-o-meter" thinks it's 4.10 but a couple of days have passed since that trip!)

[chewiebarker]

According to the January 28, 1972 pamphlet from the GM site see below:

[Mike C]

Thanks,
The chart at least agrees with my "Butt-o-meter"! I wonder how uncommon are the 4.10 geared Eaton? You see 4.57 chunks all the time. Maybe I'll score a 14 bolt detroit and some axles and see about swapping it into my Jimmy!