Biggest Tires on Stock Ram 1500 4WD: Perfect Fit

What are the biggest tires you can fit on a sock Ram 1500? The biggest tire you can fit without any additional modification is a 33-35-inch.

If you are prepared to do a bit of trimming you can fit 35-inch tires. 37-inch and bigger require fender rolling, body mount trimming, and wheel-well cutting.

The suspension is not a major limiting factor when it comes to fitting bigger tires.

With that being said, the recommendations you will get here are not to check what the maximum size wheel you can fit with limited travel and mobility.

Rather we focus on what the most practical size is to fit for on-road, off-road, and over-landing adventure applications.

• At the end of the day, you want to retain the practicality of your truck
• Your tire size upgrade should enhance your truck’s capabilities, not limit it.
• You want full articulation and droop with maximum suspension travel.

So let’s get into it and see what exactly you need to be aware of when fitting bigger tires on your Ram 1500 with a stock suspension.

Remember, once you fit a larger tire on your stock suspension and later decide to upgrade the suspension, you won’t need to change anything in terms of bump stops, levels, wheel spacers, or make any wheel-well modifications.

Biggest Tire Size on Stock Ram 1500

So this is probably one of the most commonly asked questions on all discussion forums and FB groups.

Every guy wants to know what the biggest tires are he can get away with on a factory stock suspension and stock wheels.

The biggest tire you can fit on a Ram 1500 with stock rims is 37”x12.5 

• As mentioned, you will need to do a little bit of trimming on the inside fender liner. This applies to 2500, 3500, and Power Wagon stock wheels.
• The Power Wagon wheel has a slight advantage since it has a wider offset wheel in stock form, meaning there is a bit more backspace clearance.

Biggest Tire on 2019 Ram 1500 with Aftermarket Rims

Fitting aftermarket wheels when upgrading your tires is always a smarter move.

It allows for better backspacing while not forfeiting too much in terms of offset.

Provided you don’t go to a very negative offset where the wheels protrude extensively.

A wider stance wheel with a negative offset would improve the aesthetics considerably, however, you’ll need to do a lot of Fender flair trimming which are more permanent modifications.

Besides, there could be some legality issues, depending on where you live. This could also pose a problem if you decide to sell the vehicle at a later stage.

• When selecting an aftermarket rim, you want to pay particular attention to the offset of the rim.
• The offset can be described as the distance between the inside face of the rim to the centerline of the tire.
• The measurement where the rim meets the hub, to the center of the tire is the offset measurement.

 A more positive offset (larger backspacing) moves the mounting surface closer to the outside of the wheel which will tuck the wheel further under the truck.

A more negative offset (smaller backspacing) moves the mounting surface closer to the inside of the wheel which will push the wheel further out from the truck. 

When shopping around for your aftermarket rim, try and stay between an offset measurement of +18mm to +27mm.

• This will allow for full articulation/wheel travel.
• Fitting 0 to (-) negative offset wheels might look aesthetically pleasing, however, it doesn’t translate well when venturing off-road.
• If you decide to go -18 offset rims, you’ll be required to cut a lot of sheet metal and roil the arches to make them fit nicely without rubbing.
• These are permanent modifications that are hard to undo and are not highly recommended.

Biggest Tire on 2019 Ram 1500 with Leveling Kit

Once you install a leveling kit on the Ram you are essentially increasing the wheel well area which will allow for a bigger tire.  

Now it also depends on how much of a lift you are planning, but by way of example, if you go with a 2” lift you could get away with a 35×12.50×20.

There will be no rubbing or touching against the UCA or fenders.

The biggest tire you could fit on a 2019 Ram 1500 with a leveling kit is 35×12.5×20. Alternatively a 39” with a  12.5×17.

• This is purely for aesthetics and will drastically reduce your MPG and off-road performance.
• This is not a recommended upgrade if you ever plan to venture off-road.

Will 35 Inch Tires Fit Dodge Ram 1500?

This is a hassle-free upgrade that allows for a wider and longer footprint, enhancing the truck’s off-road capability while still taking advantage of its suspension travel.

So, the biggest tire recommended for a Ram 1500 with factory stock suspension is 35” x12.50 on factory stock rims.

• This allows you to do a wheel lock without any trimming, rubbing, grinding away body panels, or adjustment of suspension components.
• This is a straight bolt-on-and-go tire option with only a speedometer adjustment needed to calibrate the reading.

Will 33’s Fit on Stock Dodge Ram 1500?

The simple answer is, yes.

As mentioned above, the 35” x12.5 is the biggest wheel you can fit without hampering off-road performance or any body-panel trimming required to make them fit on the stock wheels.

• A 33” tire will fit provided it has the correct offset to clear the brake calipers.
• The more positive the offset, the closer the wheel is aligned towards the mounting surface. The more negative the offset the further out the wheel protrudes from the mounting surface.

Below are some measurements to help you understand the differences between a 33” and 35”

Measurement	33-Inch	35-inch	Difference
Diameter	285/75/17	305/75/17	+7%
Width	11.2”	12”	+7.1”
Sidewall	7.9”	9”	13.9”
Circumference	102.7”	109.9”	+7%
Revs/Mile	617	576	-41

Next, let’s investigate the biggest tires you can squeeze on a Ram 1500 with a stock suspension.

Helpful resources

• https://realtruck.com/blog/ram-1500-tire-size-selection-guide
• I find this tool very useful when determining tire size differences and what effect it has on your truck: https://tiresize.com/comparison/

Final Thoughts

Bigger tires might look awesome, however, you want to limit how big you go, especially if you still want to maintain the full functionality of your truck.

Bigger isn’t always better since the bigger you go, the more modifications you’ll need to make as well as having to calibrate/adjust your speedometer reading.

Don’t forget, lower MPG. So, for the best all-round upgrade, we recommend not going bigger than 37”