What size is the Rear Differential?

OLIVERERIC423

MEMBER
2001 CHEVROLET SILVERADO
V6
AUTOMATIC
565,000 MILES

I've been looking everywhere and cannot find out what size my rear differential is. I have not yet opened it up but might have to. I was told that is all that's wrong with it now, and I'm wanting to get it fixed due to having an event coming up soon that's 75 miles away. The truck has had a service bed put on it and may have had a lift in the past. I'm hoping someone can help a little or give some insight on where to look. It is a 2001 Chevrolet 2500hd 8 Cylinder 6.3 liter.

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1 Reply

KEN L

MASTER CERTIFIED MECHANIC
47,640 POSTS

When you mean size do you mean gear ratio or ring gear size? These will vary with the truck build such as engine size and trailer tow packages, here are the list and what they are used for.

3.08: Generally used for light-duty applications and prioritizes fuel economy over towing power.

3.42: A balanced choice that offers a good compromise between towing capability and fuel efficiency.

3.73: This ratio is more performance-oriented, providing increased towing power and better acceleration at the expense of fuel economy.

4.10: Aimed at heavy towing and hauling tasks, offering the highest towing capacity but with lower fuel efficiency.

Are you thinking of changing the rear differential out or what is your goal?