Getting confused about tires.

Fitting oversize tires, raising and lowering, suspension modifications...

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ace
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Getting confused about tires.

Post by ace »

I have the 3.42 gears so I have been looking into 30" X 9.50 tires but all of them seem to be different diameters. Though most of them seem to be 29" overall diameter and 31' tires seem to be closer to 30". So am I right in saying that with 3.42 gears your best bet is to go with actual 29" tires? But what really gets me is that my factory tires are 28.9" overall diameter.
[size=75]2005 Silverado Crew Cab Z71
SOLD! 2003 Red Chevy S-10 crewcab ZR5. 2" PA bodylift, 1.5" spacers, CB, Airshocks, 31" Mickey Thompson MTX Tires, raised step bars, Flowmaster super 40 with 2.5" mandrel bent pipe from the Force II kit, gm vent visors, 12 volt bed outlet, airbox mod, zr5 tonneau, Bilstein shocks.[/size]
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Steve2003
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Post by Steve2003 »

I put 31x10's on my truck they were actually 29.5 But a big difference. Look at pictures of Jeggers cc witth the rear lifted and then look at pictures of my truck. You will see the difference.

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HenryJ
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Re: Getting confused about tires.

Post by HenryJ »

ace wrote:I have the 3.42 gears so I have been looking into 30" X 9.50 tires but all of them seem to be different diameters. Though most of them seem to be 29" overall diameter and 31' tires seem to be closer to 30". So am I right in saying that with 3.42 gears your best bet is to go with actual 29" tires? But what really gets me is that my factory tires are 28.9" overall diameter.
You are right.

The stock tire size is actually 235/70-15 which calculates to be 28" tall, the actual tire size is 28.2". The optional offroad tires are 237/75-15 which calculates to 29"and actually measure 28.9"

Different tires will vary due to the different casings. Import casings tend to run smaller, or so I am told.

Everyone is saying stay under 30" stock because the optional offroad tires can rub under hard articulation, mine did. Another reason to stay with the 30's is the width. While some of the 31's are closer to 30" than 31" , it is the width that makes them rub , not the diameter.

The other thing that is not in your favor is the gearing. With 29's and 3.73's it is geared really good. You have 3.42's and are already at a disadvantage. Going bigger is going to rob power. Stay smaller and you'll be alright. If you want to go bigger plan on regearing.

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jeff024
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Post by jeff024 »

this tire runs 29.3 the smallest 30/9.5/15 I could find
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Post by Justin »

weight of the tire plays an important role too but I always think that the lighter the tire, the less mileage you will get out of it. I have 3.42 with 31" BFG that really measure 30.2" i think. the truck always downshifts going up hills on the highway but I still manage 16-17mpg
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ace
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Re: Getting confused about tires.

Post by ace »

Everyone is saying stay under 30" stock because the optional offroad tires can rub under hard articulation, mine did. Another reason to stay with the 30's is the width. While some of the 31's are closer to 30" than 31" , it is the width that makes them rub , not the diameter.

The other thing that is not in your favor is the gearing. With 29's and 3.73's it is geared really good. You have 3.42's and are already at a disadvantage. Going bigger is going to rob power. Stay smaller and you'll be alright. If you want to go bigger plan on regearing.
HenryJ,

I was wondering if it was the width that made them rub and now you confirmed that. I do feel like I'm at a disadvantage with the 3.42 gears but when I get on the highway and I'm not loaded with anything I know I'm saving gas and money and gas prices blow right now. I can get about 20 mpg on the highway. I just want my truck to look more aggressive though I'm tired of people asking me if it's a 4x4. I'll be doing the body lift when it finally warms up around here then spacers and possibly the boise spring kit depending how my towing goes. I guess I'm going to go with an aggressive 30" tire. I guess 1 inch makes a big difference in power from what you guys are telling me. Thanks for the info as always.
[size=75]2005 Silverado Crew Cab Z71
SOLD! 2003 Red Chevy S-10 crewcab ZR5. 2" PA bodylift, 1.5" spacers, CB, Airshocks, 31" Mickey Thompson MTX Tires, raised step bars, Flowmaster super 40 with 2.5" mandrel bent pipe from the Force II kit, gm vent visors, 12 volt bed outlet, airbox mod, zr5 tonneau, Bilstein shocks.[/size]