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Posted

Thanks everyone for your input. I currently have 3.43 gears in my truck and was looking to get 33 inch tires. Tops maybe 35 inch but I doubt it since I don't want to lift it that high. I will take this into consideration.

 

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Posted

Thanks everyone for your input. I currently have 3.43 gears in my truck and was looking to get 33 inch tires. Tops maybe 35 inch but I doubt it since I don't want to lift it that high. I will take this into consideration.

 

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A lot of GM trucks have been coming with 3.42 gears for over 20 years. I have 3.42's and have 305/55/20 (33x12.2) the taller tires change the gearing to around 3.29, you would need to go back to a 3.56 to get it back to stock rpm, etc... Where most people notice the change is going to a 35" tall tire over stock which drops you even lower, this causes lower rpm at higher speeds, "bogging" the truck, causing it to downshift more than previous. I thing a 35" tire you would offset this with a 3.73 gear, to get back to "stock" 3.42 range performance. You also need to take into consideration more wind resistance, rolling resistance, heavier wheels/tires, so adding more gear, say 4.10 would help more.

Posted

A lot of GM trucks have been coming with 3.42 gears for over 20 years. I have 3.42's and have 305/55/20 (33x12.2) the taller tires change the gearing to around 3.29, you would need to go back to a 3.56 to get it back to stock rpm, etc... Where most people notice the change is going to a 35" tall tire over stock which drops you even lower, this causes lower rpm at higher speeds, "bogging" the truck, causing it to downshift more than previous. I thing a 35" tire you would offset this with a 3.73 gear, to get back to "stock" 3.42 range performance. You also need to take into consideration more wind resistance, rolling resistance, heavier wheels/tires, so adding more gear, say 4.10 would help more.

I disagree. Just installed a 4 inch bds lift with 285/65/20 bfg KO2's. That's a 34.5x11.5 tire. I have 3.08 gears. Yes, the engine runs at slightly lower rpms at higher speeds, but the tranny doesnt shift any more than stock. The main difference is accelerating from zero. I'm getting 18 mpg highway now and was getting 21 mpg stock.post-156672-146032998585_thumb.jpg

 

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Posted

I disagree. Just installed a 4 inch bds lift with 285/65/20 bfg KO2's. That's a 34.5x11.5 tire. I have 3.08 gears. Yes, the engine runs at slightly lower rpms at higher speeds, but the tranny doesnt shift any more than stock. The main difference is accelerating from zero. I'm getting 18 mpg highway now and was getting 21 mpg stock. 0330161709-1.jpg

 

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Hmmmm. I have a 4" lift with 305/55/20, and 3.42 gears, highway speeds here are around 80mph, my truck seems to kick down more going over bridges than it did before.

Nice ass truck, btw

Posted
Mine rub pretty bad at full lock on the inside rears. I took the lower valance off too. Fuel Beast 20x10 -18 offset. 305/55 Toyo Open Country AT Xtreme

 

IMG_5462_zpskki5t6zg.jpg

 

So, what's the zip tie/washer/magical mod that everyone keeps talking about. Haven't seen a thread about it.[/quote

 

Does that offset make the tires stick out past the fenders? Here in PA we cant have the tread out past the fender and I dont want to buy flares, thanks

Posted (edited)

2014 Chevy Silverado regular cab long bed WT2 with a 2"level, 17" Pro Comp Xtreme wheels -6 offset with 285/70R17 Mickey Thompson Baja ATZ.

post-156882-0-37577800-1460359452_thumb.jpeg

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Edited by thechainsmoker
  • Like 1
Posted

Looks great. I really like that a lot of guys are going 17s and big tires. 22s have no reason on a truck. A "real" truck that is. haha

  • Like 1
Posted
Mine rub pretty bad at full lock on the inside rears. I took the lower valance off too. Fuel Beast 20x10 -18 offset. 305/55 Toyo Open Country AT Xtreme

 

IMG_5462_zpskki5t6zg.jpg

 

So, what's the zip tie/washer/magical mod that everyone keeps talking about. Haven't seen a thread about it.[/quote

 

Does that offset make the tires stick out past the fenders? Here in PA we cant have the tread out past the fender and I dont want to buy flares, thanks

 

Yes, they do stick out.

D78968DB-44C7-4BCF-8721-B2D487103D55_zps

Posted

2.5" RC Leveling Kit and 275/65R20 Goodyear Duratracs. The tires rubbed just slightly on the fender liner, a couple zip ties solved that. Thx Mr. Drag Sledder for the tips.

 

 

IMAG01561_zpsf35deb98.jpg

Did you remove stock rear blocks and add 2" blocks from RC? How often do you tow a trailer and if so, do you notice a difference in truck handling?

Posted

Here you go. Top is before tires, bottom is after.

 

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Kerr very nice looking truck. What's the level on it in the front and did you replace the rear block? What's the difference in these tires vs 305 55 20? Thanks

Posted

Did you remove stock rear blocks and add 2" blocks from RC? How often do you tow a trailer and if so, do you notice a difference in truck handling?

 

Yes the stock rear blocks were removed and the 2" blocks from RC went in. I trailer all the time a duck boat and a Ranger fishing boat. My Ranger is a multispecies rig weighing around 5,000lbs and causes the rear to sag. It still tows fine, but you can tell you are riding high in the front. I put in Air Lift 5000 series air bags and run them at 20psi, levels everything out and tows great.

Posted

Kerr very nice looking truck. What's the level on it in the front and did you replace the rear block? What's the difference in these tires vs 305 55 20? Thanks

 

Thanks man.

 

Front 2.5" level and 2.5" block in the rear. 295's are just a tad narrower than the 305's. The difference is minimal and barely noticeable, but enough to prevent me from rubbing. I do still rub, but only at full lock in reverse. The 305's would've probably required trimming.

Posted

 

Thanks man.

 

Front 2.5" level and 2.5" block in the rear. 295's are just a tad narrower than the 305's. The difference is minimal and barely noticeable, but enough to prevent me from rubbing. I do still rub, but only at full lock in reverse. The 305's would've probably required trimming.

The 295's filled the wheel wells in just right.

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