ZR2 Oversize Tires Thread

[PBSlinger]

Yep, advertised "spec" sheet sizing doesn't always equal true installed size. I've even seen inconsistencies comparing same exact tire brand/model/size from one build date to the next.

 

[AXE]

Also ride height is affected by wheel width too. If your on stock 8.5 inch rims, I would expect them to ride a tad higher versus an aftermarket wider 9-9.5 inch wheel.

 

[Keewatin427]

Tire size (315/70R17) Mickey Thompson Baja Boss
Wheel (Method 312 17” -12 offset)
Suspension modifications
Any trimming performed (Dirt King upper control arms. Peak 1.5 inch front lift)
I needed to trim the front bumper by 2 cm and add several washers to space out the front bumper. I trimmed the plastic inner fender liner closest to the firewall and removed the bolted on crash spacers.

 

[GATORB8]

Yep, advertised "spec" sheet sizing doesn't always equal true installed size. I've even seen inconsistencies comparing same exact tire brand/model/size from one build date to the next.

100%, the brand trends in inflation sizes tend to follow a “similiar” tolerance. The 37” BFG KO2s on our Jeep are 100% smaller than the 37” Nittos Ridge Grapplers on the ZR2. Just like our old 35” KO2s were smaller than my 295/65R20 Nittos (35” sidewall stamp).

Not talking enough to change sizes you choose by brand (a 37” BFG isn’t as small as a 35” nitto), but makes a huge difference in confirmed clearance.

Make sure you match offset on an example as well. Wheel width does impact section width, so if you are going off reservation, you’ll want to adjust for UCA clearance based on the “measured wheel width”

 

[PBSlinger]

Truck: 2024 Silverado 1500 zr2 Bison
Tire: Cooper Discoverer Stronghold at
Tire size: 285/75r17
Wheel: Method 703, 17x8.5 et0
Suspension modifications: None
Any trimming performed: None
No rubbing full lock both ways

Alright so as I figured when switching from the 295/70r17s the Coopers run slightly undersized compared to others. Really glad I switched to the 285/75r17s as they are the perfect size for this tire and truck. Completely stock suspension and zero trimming I’m getting no rubbing full lock both ways, including full lock in reverse.

Will try to get more pics later, this is the cleanest these tires will ever be lol.

 

[AXE]

Truck: 2024 Silverado 1500 zr2 Bison
Tire: Cooper Discoverer Stronghold at
Tire size: 285/75r17
Wheel: Method 703, 17x8.5 et0
Suspension modifications: None
Any trimming performed: None
No rubbing full lock both ways

Alright so as I figured when switching from the 295/70r17s the Coopers run slightly undersized compared to others. Really glad I switched to the 285/75r17s as they are the perfect size for this tire and truck. Completely stock suspension and zero trimming I’m getting no rubbing full lock both ways, including full lock in reverse.

Will try to get more pics later, this is the cleanest these tires will ever be lol.

View attachment 17310View attachment 17311View attachment 17312

285s always looked good on non lifted 1500s.

 

[Leonidas]

Truck: 2024 Silverado 1500 zr2 Bison
Tire: Cooper Discoverer Stronghold at
Tire size: 285/75r17
Wheel: Method 703, 17x8.5 et0
Suspension modifications: None
Any trimming performed: None
No rubbing full lock both ways

Alright so as I figured when switching from the 295/70r17s the Coopers run slightly undersized compared to others. Really glad I switched to the 285/75r17s as they are the perfect size for this tire and truck. Completely stock suspension and zero trimming I’m getting no rubbing full lock both ways, including full lock in reverse.

Will try to get more pics later, this is the cleanest these tires will ever be lol.

View attachment 17310View attachment 17311View attachment 17312

I think the Bison AEV bumper has quite a bit more clearance than the stock bumper

 

[wutang61]

295/70R18 KO3’s
Stock wheels 3/8” spacers (effective +18 offset.)
No hard clearance issues at all in roughly 1000 miles. They just brush the inboard fender liner fabric on full crank.

I’m comfortable in saying this is absolutely as far as you can push a stock suspension truck without modifying anything.

Tires are absolutely fantastic with 45/42 pressure. Highly recommended.

 

[The_Q]

295/70R18 KO3’s
Stock wheels 3/8” spacers (effective +18 offset.)
No hard clearance issues at all in roughly 1000 miles. They just brush the inboard fender liner fabric on full crank.

I’m comfortable in saying this is absolutely as far as you can push a stock suspension truck without modifying anything.

Tires are absolutely fantastic with 45/42 pressure. Highly recommended.


View attachment 17977View attachment 17976View attachment 17975View attachment 17974View attachment 17978View attachment 17972View attachment 17971View attachment 17970View attachment 17969

Just curious, are you using extended thread lug nuts with the 3/8” spacers? Or are you just using the stock lug nuts?

 

[wutang61]

Just curious, are you using extended thread lug nuts with the 3/8” spacers? Or are you just using the stock lug nuts?

The Spacers are hub centric and use the stock studs. Plenty of engagement on the threads. No concern of a wheel falling off. Anything more than 3/8 or 10mm you will need to extend the studs.

 

[The_Q]

The Spacers are hub centric and use the stock studs. Plenty of engagement on the threads. No concern of a wheel falling off. Anything more than 3/8 or 10mm you will need to extend the studs.

Thanks! I have those spacers. I also bought extended thread lug nuts, but I don’t like the size of the nut itself. Guess I’ll give it a try with the stock lug nuts.

 

[LSnTX]

@wutang61 that looks good,
Do the 295s require the higher pressure?