What gear ratio is in a 2005 Chevy Silverado?

There isn’t a single gear ratio for all 2005 Silverados—the rear axle ratio varies by model, drivetrain, and engine. Common rear-axle options for that year included 3.42, 3.73, and 4.10, with the exact figure on your truck shown on the SPID/build tag or axle code.

Overview of axle options

Because the 2005 Silverado lineup included both half-ton 1500 models and heavier-duty 2500HD/3500HD variants, as well as 2WD and 4WD configurations, the rear axle ratio was chosen to balance towing capability, payload, and highway fuel economy. The following are among the most commonly seen rear-axle ratios for that year.

• 3.42: A balanced option found on many 1500 configurations, offering decent highway efficiency with respectable towing performance.


• 3.73: A popular middle-ground choice that improves low-end acceleration and pulling power without overly increasing highway RPM.


• 4.10: More common on heavy-duty 2500HD/3500HD setups and some towed-vehicle packages, delivering strong low-speed torque at the expense of higher engine rpm on the highway.

These figures represent typical values seen across 2005 Silverado models. The exact ratio for any individual truck can differ based on trim, drivetrain, and options.

Why gear ratios matter

The gear ratio directly affects engine RPM at a given road speed. A lower numerical ratio (like 3.42) keeps engine speeds lower at highway speeds, often improving fuel economy, while a higher numerical ratio (like 4.10) increases torque delivery for towing but raises engine RPM on the highway, which can raise fuel consumption and engine wear over long trips.

How to find your exact gear ratio

To identify the precise axle ratio for your 2005 Silverado, you’ll need the vehicle’s axle code or SPID tag. The process below explains how to locate and interpret these indicators.

• Check the glovebox SPID label: This sticker lists key configuration data, including the axle ratio. Look for a line labeled “AXLE” followed by a number such as 3.42, 3.73, or 4.10.


• Inspect the rear axle area: Some trucks carry a metal tag or stamping on the differential housing that includes the axle ratio or a code that can be decoded to the ratio.


• Decode the code: If you find a code rather than a plain number, use GM’s documentation or a VIN-based build sheet to translate the code into an exact gear ratio.


• When in doubt, contact a dealer: Provide your VIN and request the original build sheet or axle specification; this will confirm the exact ratio your truck was built with.

Knowing the exact gear ratio helps with towing calculations, tire changes, and potential gearing upgrades.

Summary

For a 2005 Chevy Silverado, there isn’t a universal rear-axle ratio. The most common rear-axle options you may encounter are 3.42, 3.73, and 4.10, with the precise ratio determined by the truck’s model, drivetrain, and options. Confirm your exact figure by checking the SPID tag, axle stamping, or the dealer-built sheet associated with your VIN. Understanding this helps with towing efficiency, performance planning, and future modifications.

What gear ratio does a 2005 Chevy Silverado have?

Gear ratio 3.42. With 8.6 Ring Gear.

What is the gear ratio for a 2004 Chevy Silverado 1500?

You should look for GT3=3.42, GT4=3.73, and GT5=4.10. It will appear as follows. You have a GU6, which has a ratio of 3.42.

How do you tell if you have 3.73 or 4.10 gears?

You can tell if you have 3.73 or 4.10 gears by manually counting, checking the differential cover for a tag, or finding the ratio stamped on the ring gear. The most direct method is to lift the rear wheels, rotate one tire one full revolution, and count how many times the driveshaft turns; 3.75 turns indicates 3.73 gears, while slightly over 4 turns indicates 4.10 gears.
 
This video demonstrates how to check your gear ratio by counting the driveshaft turns: 48sBent Motorsports OffroadYouTube · Sep 22, 2023
Method 1: Manual count (with the vehicle jacked up)

1. Jack up the vehicle: Safely lift the rear of your vehicle and secure it on jack stands. Ensure the wheels are off the ground. 
2. Mark the driveshaft and a tire: Place a mark on one of the rear tires and a corresponding mark on the driveshaft. 
3. Rotate the tire: Rotate the marked tire forward one full revolution. For an open differential, you may need to lift only one wheel and have someone hold the other stationary, or lift both wheels and rotate one tire twice while the other tire is on the ground. For a locked differential, lift both rear wheels and have one tire rotate once while the other rotates once in the opposite direction. 
4. Count the driveshaft turns: Count how many times the mark on the driveshaft has rotated. 
   • 3.73 gears: The driveshaft will turn approximately 3.753.753.75 times for one full tire revolution. 
   • 4.10 gears: The driveshaft will turn a little over 444 times for one full tire revolution. 

Method 2: Check the differential cover tag 

1. Locate the tag: Look for a small metal tag that is usually bolted to the differential cover. It may be on one of the bolts. 
2. Read the ratio: If the tag is still present, the gear ratio will be stamped on it. It will likely be a number like "3.73" or "4.10". 

You can watch this video to learn how to find the differential cover tag: 51sFlawed OffroadYouTube · Apr 18, 2022
Method 3: Read the ring gear stamps 

1. Locate the ring gear: This requires removing the differential cover to get a clear view of the ring gear.
2. Find the numbers: Look for two numbers stamped on the teeth of the ring gear, such as "41" and "11". 
3. Divide the numbers: Divide the larger number (teeth on the ring gear) by the smaller number (teeth on the pinion gear). 
   • 41÷11≈3.7341 divided by 11 is approximately equal to 3.7341÷11≈3.73 
   • 41÷10=4.1041 divided by 10 equals 4.1041÷10=4.10 

This video shows how to read the ring gear stamps to find the gear ratio: 46sJL LIFE OFFROADYouTube · Nov 18, 2022

How do I tell what gear ratio my Silverado has?

Identify your GMC or Chevrolet rear end gear ratio by the RPO Codes, usually located on the placard labeled “Service Parts Identification” inside the drivers door panel or glove box. Note that using the RPO code for parts identification assumes that the rear end has not been previously modified!!