new tires

[cimfth]

I have a 78K20 with 4.10 gears I heard bigger tires would lower my rpms at cruise and give better mileage? I am pretty sure  it will fit 33's ? How big of a tire would fit? 35's ? It has no lift but sits higher because it is a 3/4 ton. I measured and it looks like they would. I want a normal width nothing real wide.  

[smokin77]

Well my 85K10 had 32" tires on it with no problems, before you buy the tires see if you can find some 33's or 35's to try on the truck(a friend or relative maybe?), the front should be the only area you would have to worry about fender clearance, I think I could fit 35s on the rear of my K10. But if you can, it never hurts to to try em on first!

[Sierra4x4]

here's what i know about the subject. I only have about a 3.42 gear or so and i run 35's. My highway mileage is great, around 2000 rpms for 60 mpg. However the city is really bad, because i dont have enough gear to get them moving quickly. Bigger tires will definetely help you out especially on the highway. i youll notice a small change with 33's i would go at least a 35 though, you could fit 35's up front with a 4 in lift or maybe alot of trimming. I rub slightly but im running wide mud tires.

[smokin77]

I tryed 33" mudder on the driverside of my stock 85K10 and it rubbed the fender a little bit. Looks like I'm not gettin 33's without add-a-leafs or a lift! Im not gonna trim the fenders either!

[chevanonymous]

33's should fit depending on how bad your springs are worn.
my 3/4 ton suburban had 33's when i bought it. they rubbed only slightly when turning on very uneven terrain.
now i have a 6" lift with 37's.