Tire Size

[PasoStepperProject]

Hey Guys.

I am restoring my 76 GMC K15 stepside. It has 31x10.5x15 tires on it. My new frame I got from a guy has a 4" easy ride lift kit (all springs) on it. The 31's look ridiculous.... I can pick up (5) BF Goodrich 33x10.5x15 tires for $400 bucks! They have about 100 miles on em!

My question is will the 33's fill the gap? Would 35's be better? My truck has a stockish 350 with a SM465 Trans. I love the 4spd so getting bigger tires to turn is not an issue.

Does anyone have a pic of a truck with a 4" lift running 33's?

The deal is so good its hard to pass up!

Thanks in advance for your help!

[19silverado77]

my truck is running 33s and a 4 inch lift it looks alright to me.

[Stocker]

A 33'" tire has 1" greater radius than a 31" tire, so it will be just 1" closer to the fender. It'll be an improvement but won't fill the gap by a whole lot.

[PasoStepperProject]

Thanks for the reply. Any chance I could see a pic of your truck. I do better with pictures!

Thanks again!

[PasoStepperProject]

Stocker: I am confused. I thought a 33 was approx 2" taller as long as I go with the same width and rim? Can you educate me further? so would a 35" be a better option? the truck looks funky on the 31's. the tires are pretty worn down but my buddy will use them on his CJ5 Jeep for sand!

can you help me out?

[JointTech]

2" taller yes but it only adds 1" to the radius, so its only an inch closer to the fender. I think you need 35's. 33's arent going to get you much more. You can fit 33's on a stock truck.
diameter = height of tire = top of tire to bottom.
radius = center of tire to outer edge.

[Stocker]

^ Exactly as he said. Radius = 1/2 of diameter.

Or think of radius as distance from center of hub to outer edge of tire.

[PasoStepperProject]

wow that is a very simple explanation. kinda feel dumb. makes perfect sense. so 35's here we come! course I gotta find the money now!

thanks for the help