305/65R18 or 285/75R17???

Tay2610 · February 7, 2023

I'm wanting to upgrade my wheel and tire's on my 2022 Silverado Z71 Duramax. I've given it some thought and I don't want to go much beyond what's been factory options (33's). My stock tire's are the 275/60R20's. I've settled on these two tire sizes for the time being and would like some input from the community. The 305/65R18 does seem to be flirting with control arm clearance as I've read that my stock setup may even come into conflict with certain aftermarket UCA's (Camburg billet). I've attached some screen shots of an offset calculator that I've been using for comparisons.

The aftermarket wheels I'm looking at for this setup do have less positive offset and there for the tire is less than a 1/4" closer to the UCA. I've measured my stock setup and it seems as though this would work as I currently seem to have at least a 1/2" to 3/4". Maybe my bigger concern is the added 1" added outside? I would like to retain the factory mudflaps and wheel well liner. Any experience with running this setup or information about clearance's would be helpful. I've also thought about running a 17" wheel as I really like the look of tall sidewalls. My other thought is to run a 285/75R17 on a 17" rim with a 0 offset. This would definitely help with any potential control arm issue's but it would cause the tire to stick out about 1 1/4" from stock sizing. Would this cause any clearance issue's? This may be my preferred combo, due to the taller sidewall and plenty of control arm clearance.

Any input is appreciated. I do plan on leveling the truck. My current thought is 5100's or Fox2.0 IFP. Do I need to know anything about these working on a Duramax? Thanks for your time.

PS...I've attached a screen shot of the two tire sizes in question as compared to one another. I would also be able to run the tires I’m wanting with a “C” load rating at 305/65 vs an “E” rating on the 285’s. Would this be helpful with dampening the harsher ride from the 5100’s?

Edited February 7, 2023 by Tay2610

Tay2610 · February 8, 2023

Here’s a picture of my Truck at the moment.

Ronjon · February 10, 2023

More side wall will act as a secondary dampener. IMO 17's look better.

Tay2610 · February 13, 2023

Thanks for the response @Ronjon. I agree that 17's will look better. As far as fitment, has anyone had success running this type of setup without trimming or the removal of mud flaps? I've heard that running a 0 offset can cause clearance issues and I've seen conflicting results on the internet so far. I'm also assuming that there won't be issues with fitment in regards to the wheels themselves and the brakes/caliper?

Tay2610 · February 27, 2023

So far I've only been able to locate one Silverado, on-line, that is running 285/75r17's on a 2020 Silverado with a leveling kit. They claim no rubbing or cutting necessary. I would like to see other setups if available. Please let me know if you know someone or have links to trucks with this setup, thank you. 285/75r17's on 17x8.5 wheels w/0mm offset. I plan on adding 5100's front and rear in order to level the truck. I'm also wanting to find out people's experience with running 5100's with the LM2 engine. Bilstein's own installation instructions seem to have some conflicting information in regards to "leveling" with this engine.