If you are planning a big tire upgrade on your Silverado 2500HD but are not sure which option is best suited for your stock truck, then this article can help you. This article covers the biggest size tire you can fit without the need to fiddle with your truck’s torsion bars or the fitment of aftermarket leveling kits to your Silverado 2500HD.

The biggest tire you can fit a stock Silverado 2500HD without a lift is a 35-inch tire with a metric value of 285/75/R18. The recommended 20-inch tire on stock rims without any offset changes is 315/60/20 or a 35×12.5×20.

Before fitting bigger tires to your Silverado 2500HD, It is important to remember that in some cases, depending on how large you go, larger tires may require modifications to your truck’s suspension, fender flares, and potentially the recalibration of the truck’s speedometer to accommodate the larger tires rolling circumference.

Secondly, be aware that larger tires can also have a negative effect on the overall fuel consumption and handling of the vehicle, including acceleration, braking, and fuel efficiency, so keep that in mind when doing a tire upgrade. But more on that later…

Let’s now look into the upgrade options in more detail.

Table of Contents

Biggest 18” Tire on a Stock Silverado 2500HD Without a Lift

After doing extensive research, many owners are reporting that certain size 35s on 18” wheels are the go without additional modifications. If you choose to go bigger than 35s to 37s you can opt to crank the torsion bars or fit a leveling kit, however, there seems to be a general consensus that “cranking” torsion bars definitely creates a stiffer ride. A leveling kit will be a better option in my opinion.

There are Silverado owners who reported to have fitted 37” tires in the form of 37×11.50 on the stock wheel with the torsion bars turned up a bit (not maxed out) and claim that this does not rub. Keep in mind when you go this big there will be some additional modifications like pulling the front of the fender liners forward for additional clearance.

So the feedback we got from most Silverado owners who have done this modification is that 285/75/18 which is actually a 34.8” will be the safest option without having to fiddle with torsion bars or leveling kits. Larger 35s and 37s require additional modifications since they will rub with the stock suspension setting. So, for example, a Nitto Ridge Grappler tire with the size of 285/75r18 is the go here. It’s not a true 35” tire but it’s pretty close.

Below are some possible upsizing options for the Silverado 2500HD.

Size	Diameter	Width	Height
285/75/R18	34.8”	11.2”	109.4”
295/70/R18	34.3”	11.6”	107.6”
305/70R18	34.8”	12”	109.3”

Biggest 20-inch Tire on Silverado 2500HD without a lift

When doing any big tire upgrade, it is recommended to stay within the 3-5% increase parameters to avoid unnecessary complications. Certain owners are claiming they have successfully fitted 35s in the form of 35×12.5×20 Toyo Open Country ATIIIs. This is without any key cranking of the torsion bars or aftermarket wheels with a bigger offset. The tire mold could play a part since not all tires are created equally and manufacturers use different molds for the same size. A different brand like a BFG KO2, for example, might be a different story. I would exercise caution here and it would be best to find a tire shop that has the time to fit various sizes and brands before you commit.

Owners who have successfully fitted 35s have tested and compared fuel usage before and after figures and claim the 35s only made a 1-1/2 to 2 MPH difference. The actual speed was only thrown out by +1 to 1.5mph.

Below are some options for 20-inch tires:

Size	Width	Diameter	Height
35×12.5×20	12.5”	35”	109.9”
295/65/20	11.6”	35.1”	110.2”
315/60/20	12.4	34.9”	109.5”

Understanding Tire Sizes

Most people look at the information printed on the tire sidewall and have absolutely no clue what it means. There are so many numbers that can be quite confusing, BUT, it doesn’t have to be. Below is a simple breakdown of what all those numbers and codes mean.

Let’s use this tire size (265/70/R17) to explain.

265	Refers to the tire’s width and is measured in millimeters
70	Refers to the tire’s aspect ratio, which refers to the tire’s sidewall height and is measured in percent (%). It refers to 70% of the 265mm tread width.
R17	Refers to the tire’s width and measured in millimeters

NOTE: A tire’s actual size may not be exactly as printed by the manufacturer. Tire manufacturers use their own tire moulds which differ slightly between brands. Different designs and tread patterns may cause a slight size difference between tires that have the same size codes. This means that a tire from brand A might fit your truck but one from brand B of the same size won’t.

Pros and Cons of Bigger Tires

Big tire upgrades are one of the most popular, if not the MOST popular upgrades owners make to their vehicles, and with good reason. For many, it’s a case of an aesthetics improvement and practicality upgrade, while others seek the best off-road capabilities and driving characteristics their trucks can offer.

…as is the case with most modifications, there is always a trade-off

With that being said, as is the case with most modifications, there is always a trade-off. With bigger tires come a few pros and cons you simply cannot ignore, so make sure you proceed armed with all the relevant information at hand.

With taller and wider tires you get the following:

Let’s start with the Pros first.

Increased ground clearance
Improved approach angle
Improved departure angle
Improved Break-over angle
Increased wading depth.
Wider tires increase your vehicle’s traction, both on and off-road
Improved control and handling.
Better control on slippery surfaces such as sand, snow, and mud.
Improved stability due to the wider tires
Improved aesthetics

Some of the Cons Include:

Increase in fuel consumption (Less mpg)
Expensive tire replacement costs
Increase in stopping distance (Longer stopping time)
Decrease in acceleration
Decrease in overtaking speeds
Slight Understeer feeling
Inaccurate speed readings (Size Dependant)
More wear on certain suspension components
A requirement for aftermarket suspension component upgrades (Size Dependant)

Armed with the above intel now allows you to make a more educated decision as to whether your desired upgrade is worth the cost outlay. If the vehicle is your dedicated weekend trail warrior and not your daily driver then you can go bigger with more aggressive tread patterns, however, if this is your only vehicle then it would be wise to stay within the safe zone of not exceeding the recommended 3% to 5% increase of your stock tire’s size. This will minimize the disadvantages to a degree.

Watch – Silverado 2500HD Wheel Fitment Guide (VIDEO)

User Experience and Feedback

Let’s look at a few real-world user experiences and feedback directly from owners who have successfully fitted bigger tires.

User Experience #1

You can fit 35s all day without modifications. If you level the truck via cranking torsions or a leveling kit you can fit 37s. Both will rub some but not too bad. If you start changing wheels to different widths and offsets from the factory you will rub more or need to start trimming.
https://www.duramaxforum.com/threads/biggest-tires-on-a-stock-2022-chevy-2500hd-z71-duramax.1017932/

User Experience #2

I just put 35’s on and they are fine. No adjustments. Looks like I could have gone a bit bigger, but next size up in the tire I wanted was 37. I went with Nitto Ridge Grappler 285/75r18.
https://www.duramaxforum.com/threads/biggest-tires-on-a-stock-2022-chevy-2500hd-z71-duramax.1017932/page-2

User Experience #3

Had 275/65-20’s. So only 1)2 in ride height. Added about 1.7 inches in width. But I like the more aggressive tread. I was hoping for a bigger look but was afraid to go bigger. 14.5’s would look really good but might need a spacer, not sure. I would think 37’s would fit as well but I ordered these online and wanted to make sure they fit. Didn’t change the handling much. Hope this helps.
https://www.duramaxforum.com/threads/biggest-tires-on-a-stock-2022-chevy-2500hd-z71-duramax.1017932/page-2

Resources

Conclusion

Variations in fitment options based on user feedback can be inconsistent at best. This is mainly due to construction variables from different manufacturers. In some cases, a certain tire brand will fit a vehicle perfectly, while others of the same size from a different manufacturer will not. This is mainly due to the fact that tire manufacturers use their own tire molds which differ slightly between brands.

Biggest Tires on a Stock 2500HD Silverado (W/Without A Lift)