If you’re interested to find out what the biggest tire is you can fit on your MR Triton running on stock suspension, then you’ve come to the right place. Tire upgrades are usually one of the first and most popular modifications to off-road trucks since it’s the quickest way to get a more aggressive look with better traction on and off-road.
The biggest tire you can fit on a MR Triton with stock suspension and stock rims are 235/85/16. This size fits without any rubbing problems, and no trimming or additional modifications are required to make them function properly.
Factory standard tires on the MR Triton is between a 245/70R16 or 245/65R17 or 265/60/18 which all roughly equate to 29.5”to 30.5” in metric sizes. The MR Tritons biggest downside is the lack of off-road clearance. If you ever intend on taking this vehicle off-road then it is highly recommended to invest in a quality 50mm lift kit. The best way to improve ground clearance and off-road ability is by fitting a larger set of tires.
Let’s now look in more detail at what the best tire option for a MR Triton running a stock suspension
Biggest Tires on a Stock MR Triton – No Lift
Wide vs Tall Tires
Most problems with fitting bigger wheels to your truck is caused by the width of the tire. A wider tire looks really impressive but it causes a lot of clearance complications. The aspect ratio or sidewall size is what improves your ground clearance so a taller skinny tire can do just as well with less complications. Fitting a 235 width tire to a stock MR Triton with a taller sidewall is your best option here.
Poke
Another problem caused by wide tires is the “poke” issue. Every country has their own regulations regarding this and some countries are stricter than others. Poke occurs when you fit a wide tire like a 33-inch or 35” tire with a 285 or 305 width which results in the tire protruding from the arch. Fitting a skinnier 235 or 245 width tire eliminates this problem completely.
Trimming
If you decide to go wider like say a 265/70/16 you will need to do some trimming on the inner mud guard. IT will catch there and scrub at full lock. Again the 235 in a 16-inch tire will be the tallest and best suited option when running a stock suspension on a Triton MR. Running the 235 width on the 16-inch compared to the 265 width in the standard 18-inch tire is roughly 10% narrower but offers you more than a 25% increase in sidewall height.
Wheel Arch Clearance
A wider tire needs to clear the front inside fender guard, cab side mounts, UCA, as well as interior fenders. The wider you go the more difficult and expensive this upgrade becomes. You’ll need to invest in a more negative offset wheel for improved backspacing and clearance in these areas, alternatively in a set of wheel spacers.
What do the MR Triton Owners Say
Just fitted LT235/85/R16 Yokohama G015 ATs. These are a 32 inch tire in the old money. I have a 2019 GLX+ automatic dual cab with stock suspension.
https://www.newtriton.net/phpbb/viewtopic.php?t=22175
I decided to get a skinnier all terrain tire to reduce rolling mass while getting improved clearance and Light Truck Tire quality.
The auto transmission doesn’t seem “too” bothered with the extra size and weight either. Affecting the torque converter was what I was most worried about. I previously owned a 2012 Mitsubishi Challenger and the auto transmission didn’t like the bigger heavier tires. The torque converter was always slipping to help spin the LT265/70R17s I put on it. Everything still worked fine but my fuel economy suffered as a result. Those tires were Kelly safari TSR (great tire, however pretty heavy duty with deep tred and lot of weight).
Honestly this is as big as you’d be able to go with a stock set up. The only reason it doesn’t rub is the width of the tire 235mm (9.3inches).
I have Niito ridge grapplers 265/65/18 on a Premium with standard rims. no rubbing at all.
https://www.newtriton.net/phpbb/viewtopic.php?t=22175
What about Your Spare Wheel?
If at a later stage you decide to upgrade your suspension to accommodate a bigger, let’s say, 33-inch tire then the 285/70/17 is the largest tire that can be squeezed under your tub without any modifications.
Will the 235/85/17 throw out your MR Triton speedo?
In many cases when you upgrade from a stock tire to a taller one, your speedo can be thrown out and might require recalibration. In this specific instance with the diameter being a 7.5% increase and an 25.4% increase in the aspect ratio the speedometer will be thrown off somewhat. The 7.5% increase in tire circumference means the actual speed will be higher by up to 6.7 mph @90mph
The below table will give you an indication of how the speedometer reading is affected.
| Speedometer reading | 20mph | 30mph | 40mph | 50mph | 60mph | 70mph | 80mph | 90mph |
| Actual Speed | 21.5 | 32.2 | 43 | 53.7 | 64.5 | 75.2 | 6 | 96.7 |
Below are the actual differences between the stock tire and the upgraded 235/85/16
| Measurement | Stock Tire (245/65/17) | Upgrade (235/85/16) | Differences |
| Diameter | 29.5” | 31.7” | +7.5% |
| Width | 9.6” | 9.3” | -3.1% |
| Sidewall | 6.3” | 7.9” | +25.4% |
| Circumference | 92.8” | 99.6” | +7.5% |
| REvz/Mile | 683 | 636 | -47 |
How Does 33” Tires Affect Fuel Economy on a MR Triton
Increased unsprang weight is the quickest way to increase fuel consumption. The heavier tires and rolling mass affects the consumption directly since it’s positioned below the suspension, which means, the engine, transmission, CV Joints, and other drivetrain components are required to work slightly harder to move and rotate the heavier wheels. This is especially obvious when pulling off.
So, before you do the big tire upgrade, make sure you understand your fuel economy WILL be negatively affected! Sure, your truck will look more aggressive, have better traction, and perform better off-road, however, it all comes at a price. Also, depending how big you go, it might not even be more than 4kg heavier per wheel, however, this makes a substantial difference in torque applied on the wheels.
Resources
- Triton 2-inch lift kit
- Triton MR Wheel Spacers
- Triton 3” lift Kit
Conclusion
When doing a tire upgrade, there are so many variables to consider before running out and dropping a load on some expensive over-sized tires. Your first and foremost exercise, should be to determine what your primary purpose for the upgrade will be. Is it purely for aesthetics or will you need maximum practicality, off road ability, while maintaining articulation.
Do you need more load carrying capacity, which means the tires load rating will be an important factor? Also, what other accessories are you planning on fitting to the truck at a later stage? Will you be towing? This will determine what kind of suspension package you should opt for, which might impact the maximum recommended tire size.
However, if the main purpose for the tire upgrade is for improved aesthetics, and you have no intention of venturing off road, apart from the occasional dirt road then your stock suspension is more than up for the task and you will not need to lift the truck. In most cases a truck with a stock suspension can actually accommodate the same size tire as a truck with a 2″ lift but without the flex.