Fit bigger tires
Seven steps from today’s tires to a plan you can keep. Leave anytime: your place saves with the plan.
The steps
- 1
Truck and setup
What’s on the truck today?
Today’s tire size, lift, gear ratio and bumpstops are the baseline the plan is measured from.
- 2
Pick the size
Which tire size?
Height sets everything after it: clearance, gearing, speedometer, brakes and weight. Tire size lists the popular sizes for your wheels, 35s included.
Answered byTire size
- 3
Will they fit?
Will they fit?
A taller tire can reach the fenders, the body mounts and the bumper corners at full stuff, so check rub before you buy.
Answered byClearanceSuspension
- 4
Gearing
Do you need to regear?
A taller tire is a taller final drive. The calculators suggest a ratio; you pick one or skip it. The path never forces a regear.
Answered byRegearCrawl ratioSpeedometer
- 5
On the road
What does it cost on the road?
Bigger tires take acceleration and hill speed, and use more fuel per mile.
Answered byPowerFuel and range
- 6
Weight and brakes
What do the weight and brakes need?
Heavier tires and wheels load each axle against its rating, and a taller tire needs more brake torque to stop like stock. Mind the spare too.
Answered byTire sizeBuild sheet
- 7
Review
Review and keep
What changed against Actual, cost and weight where known, and the open checks.
Each step opens a calculator with your truck filled in. Start with Tire size, then Clearance and Suspension to check rub, Regear for gears, Power and Fuel and range for what it costs on the road, and the build sheet for weight. With JavaScript on, this page keeps your place and your answers in My garage.
Bigger tires, answered
Do I have to regear for bigger tires?
No. Most trucks feel fine up to about 5% taller than stock. Past that the Regear calculator suggests a ratio that gets the truck back to stock feel, and you pick one or skip it. The path never forces a regear.
How do I know if bigger tires will rub?
Measure. Clearance works out the bumper corners and angles from five tape measurements, and Suspension shows where each wheel goes at full stuff. A rub nobody has checked stays an open check: unknown never counts as fitting.
Will my speedometer be off?
Yes, by the change in tire height. A 35 in tire on a truck that came on 31.6 in tires reads about 9.7% low, so a true 65 shows as 59. The Speedometer calculator gives the figure to program.
Do bigger tires need bigger brakes?
A taller tire is a longer lever, so the same brakes stop it with less force at the ground. Past about 8% more brake torque needed, we’d upgrade. Tire size works it out with the heavier tires and wheels counted.
Use at your own risk. These calculators are here to help you plan and to inform your decisions, not to sign off on a build. Many numbers are estimates worked out from factory figures, and some factory figures are not yet confirmed. Check every number against your own truck, its manuals and a qualified shop before you buy parts, cut, weld, lift, regear or drive on it. Long Range Desert Tools is not liable for anything you do based on these calculators or their results. The full terms are in our policies.