[fire resque]

How do I tell what size ring gear I have in my diffs to know the fluid capacity for my 1500. Can you tell from the VIN. This is what ALLDATA says.

DRIVE AXLE CAPACITIES
Front Drive Axle (8.25") 1.43 liters (1.51 quarts)
Front Drive Axle (9.25") 1.73 liters (1.83 quarts)
Rear Drive Axle (8.6") 2.03 liters (2.15 quarts)
Rear Drive Axle (9.5") 2.6 liters (2.75 quarts)
Rear Drive Axle (9.75") 2.84 liters (3.00 quarts)
Rear Drive Axle (10.5") 2.6 liters (2.75 quarts)
Rear Drive Axle (11.5") 3.0 liters (3.17 quarts)

 

[Rambodog]

Here is an instance where you don't have to know exactly. When filling the diffs you fill them till a bit of fluid comes out of the top hole your filling. 5 or 6 quarts should be enough to do both front and rear.

 

[esox07]

I think you are mixing up the metric system. A liter is just a touch more than a pint. There are just a little more than two liters per US quart. Two quarts is all you should need. And like Rambodog says, just fill it until you start to get it running out of the fill hole.

My 2013 manual actually states this:
Rear Differential:
To get an accurate reading, the vehicle should be on a level surface.
For all 4.3L, 4.8L and 5.3L 1500 Series applications, the proper level is 1mm to 19 mm (.04 in to .7 in) below the bottom of the fill hole, located on the rear axle. Add only enough fluid to reach the proper level.

For all 6.0L and 6.2L 1500 Series applications, the proper level is from 15 mm to 40 mm (0.6 in to 1.6 in) below the bottom of the fill plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

For all 6.0 L 2500HD Series applications, the proper level is from 0 mm to 13 mm (0 to 0.5 in) below the bottom of the fill plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

For all 6.6 L Duramax Diesel 2500HD Series applications and all 3500 Series applications, the proper level is from 17 mm to 21 mm (0.6 in to 0.8 in) below the bottom of the fill plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

 

[Tatsngats]

That's incorrect. A liter is just a touch more than a quart. There are exactly 3.78 liters in a gallon.

 

[esox07]

Yah, your correct.
My bad.
I did both my differentials with a 6 quart case of 75W90, so if OP gets three quarts, he should be good to go. Can always return the extra quart if it isn't needed. But it is always nice to have a quart or partial quart laying around to top them off every so often.

 

[19trax95]

I buy 5 quarts when I do my front and rear diffs and if I use every drop, it's the perfect amount with none left over.

Sent from my SM-N910V using Tapatalk

 

[mikesteelman2015]

This has helped me with my '09 Sierra 1500 5.3L RWD which has a 3.55 gear ratio with a 8.6" rear diff. Find out size of differential and gear ratio and cross reference ( If you don't want to go by the finger in the drain plug method. BTW front and rear fluid is different. Front specifies that it be GL-5, at least in my case.

2007-13 Chevy Silverado/GMC Sierra Truck Routine Maintenance FAQ

Modern cars and trucks need much less maintenance than the vehicles of 25 years ago, but they still have needs. You no longer have to do a tune up every six months, or change the oil every three months, but regular oil and fluid changes and tire rotations are still essential to your vehicle’s...

haynes.com

AND

GM RPO Codes - Axle Ratio and Differential Identification - West Coast Differentials

Use the GM RPO codes on the label in your glovebox or on drivers door to determine axle ratios and more. Decipher the factory codes and get the right parts!

www.differentials.com