Tundra Tire Questions – Low Pro’s, 33′s, or 35′s?
What’s the first upgrade you think of for any aggressive-looking new truck like the Tundra? Wheels and tires, of course! Whether your taste runs to urban chic with a low profile hint of tire peaking over massive wheels or the super-lugged, gnarly off-road tires in search of mud, you want to stamp that truck with your own style, right?
Check out these photos of a featured Tundra (A Prize-winning Tundra) with a 6″ Pro-comp lift and 35″ tires.
A few after-market wheel companies have come out with larger rims mated to low profile tires that maintain the diameter of the stock package. This is pretty exciting considering the fact that Toyota went with an odd bolt pattern for a half-ton – 5 on 150mm. If your favorite roads run to dirt, mud, sand and rocks and you crave the kind of traction gained with monster flotation tires, you’re probably limited to 33-inchers, just about an inch over stock. They’ll do the job just fine, but they lose a little in the gnarly category.
To figure out your max tire size while staying within 10-percent of stock diameter, you have a couple of options. You could simply measure the diameter of the tires on your Tundra and add 10%, but you wouldn’t get the opportunity to use the math you learned in school. The stock tire size for a Tundra is 255/70R18. The 255 represents the width of the tire in millimeters; 70 is the percentage of the sidewall height in relation to the width. Since flotation tires are measured in inches, you have to work the conversion factor into the tire size formula which goes like this:
Tire width (255) divided by a conversion factor (25.4) = width in inches (10.04)
Tire width in inches times percentage (70) = sidewall height in inches (7.03)
Two (2) times sidewall height in inches (7.03) + rim diameter in inches (18) = 32.05 inches overall height of the factory tires.
Hypothetically, you could jump to 35-inch flotation tires and stay within the 10% limit, but since there are some guidelines that recommend staying within 3-percent of factory tire size, conservative tire dealers (read most tire dealers) insist 33-inches is the limit.
Here’s a featured Tundra (Michael’s Trick Doublecab) with a set of 33′s.
There are some downsides to going with bigger tires. First of all, you’ll loose some low-end torque (especially when you go 10% bigger than factory). Fortunately, the Tundra’s 10.5-inch 4.30 ratio is so beefy you could loose a bit of torque and never miss it. Also, a vehicle’s ECU is programmed for shift points, speedometer and odometer readings based on the stock diameter. If you go big, you’re going faster and farther than the system realizes. While most of us can live with misreads on our gauges, you can’t use “I’m over stock diameter, officer” as an excuse to get out of a speeding ticket.
Most premium full-sized truck re-programmers will recalibrate all of the above for over-sized tires, but, you guessed it, none have programmers for the Tundra. Hypertech, however, does offer an in-line speedometer calibration unit that plugs in behind your dash and corrects your gauges. If you go bigger than 33″ on a new Tundra, it might be wise to invest in one.
If you’re feeling deprived by the lack of wheels on the market (no to mention re-programmers) just stand back and look at how nicely the stock wheel or optional 20-inch rims fill up the Tundra’s wheel well. You’ve got tire options and as more new Tundra’s roll out of the showroom, the aftermarket will eventually catch up.
Filed Under: Toyota Tundra Accessories