Differential ratio identification

History and Identification of Chevy 10 and 12 Bolt Chevy Differentials
10 bolt GM rear end codes
10 Bolt Identification Guide Tech Article Chevy High Performance Magazine
Chevy Axle Rear End Suffix Decoding and Identification
https://www.hemmings.com/magazine/hmn/2009/03/GM-10-bolt-8-5-inch-Differentials/1781844.html

Hello Brenda...you will find some identifying information on the actual real axle casing. Stamped numbers, I.D. tag or you can search your VIN (Vehicle Identification Number) or make, model year and series on the internet to see what options were available for rear end gearing ratio's.

Yes you should stick with a similar or identical rear end to ensure proper mounting bracket alignment and gear ratio choices. Dana Model 60, 70 & 80 Axles are not internally identical.

Looks like the standard differential carrier for the E150 is a 8.8" (*10 bolt). Standard, Includes Spider gears, 31 spline, 7/8" shaft.

* Ten Bolt - The rear end cover plate contains 10 mounting plate bolt holes.

Tag should be on rear differential cover. If its two wheel drive, it don't much matter what ratio you put in, except for the speedo will be off. GM 10 bolts are a dime a dozen.

The ratio is normaly printed on an identification tag fitted to the differential ie. 9.3-1 In other words your pinion turns 9.3 times for everytime your crown wheel turns once. if the differential is open you can also determine it by counting the teeth on the crown wheel as well as the pinion and deviding the pinions amount of teeth with the crown wheels.

i dont believe the ratio is supplied by the vin but the ratio is written or stamped on the tag on the rear end, or front differential

I would call the dealer parts dept. they should be able to tell you what you need to know. there may be a difference in gear ratio for each engine/ trans combination. A salvage yard may be able to help you , they should have a computer system showing what rear is compatible. there should be a code on the axle housing itself.

cardan centering bearing
point bolts needed to be removed that connects D.S.to transfercase

They were an option but you can find out by looking in your glove box's GM RPO Codes. It's the sicker on the inside of the glove box with numbers and letter.
Here are some listing on the gear ratio you may have,
U4: Rear Axle, 3.08 Ratio             U5: Rear Axle, 3.23 Ratio U6: Rear Axle, 3.42 Ratio 
If it is a GU the G stands for the rear Locking Differential.
Good luck and hope this helps.

Here are the Fluid CAPACITIES & MORE:
Engine, with filter..........4.6 quarts[1]
Cooling System, Initial Fill..........12.0 quarts
Automatic Transmission, Total Fill
4 speed 4L60, 60E..........11.0 quarts
Manual Transmission, NV1500..........5.7 pints
Manual Transmission, NV3500..........4.2 pints
Differential, with 8.6 ring gear Rear..........4.0 pints
Differential, with 7.25 ring gear Front..........2.5 pints[2]
Differential, with 8.25 ring gear Front..........4.2 pints[2]
Differential, with 9.25 ring gear Front..........5.9 pints[2]
Differential, Front..........2.5 pints
Differential, Rear..........4.0 pints
Transfer Case,BW4472..........2.5 pints
Transfer Case,NV136/236/246..........4.0 pints
Transfer Case,NP207..........4.6 pints
Transfer Case,NP231, NP233..........2.3 pints[3]
Transfer Case,NV231/233..........2.1 pints[3]
1. After refill check oil level.
2. Do not use synthetic lubricant in axles using RTV sealant.
Synthetic lubricant will chemically atack RTV sealant.
3. Identification: check tag on case.

yes the first 3 digits 411 is your ratio and they should be on the other rears the same way they have to match the front rear end