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Posted

Anyone here running a 17x9 with -12mm offset on a 2.5" rc level. Either a 285/70r17 or 33x12.50r17

Posted

Just bought a 2015 1500 Z71 crew cab with 7K miles. I'm wondering if it has already been leveled? I haven't taken delivery yet.

1.jpg

Posted (edited)

after further evaluation....it looks like the rear is higher than the front.

 

85d4d8aa-2789-4dd8-92fc-073a25e1581e.jpg

Edited by Brian2015
Posted (edited)

If anyones curious and likes a little bit of rake (im a muscle car guy so to me it looks aggressive). I used the 2.5 RC kit and left the top .5in spacer off the front. So 2in front. 1in rear(2in rear block). Im happy. Truck looks stock, just higher. Went with 275/65/20 bfg k02s... dont rub at all. Wish i went bigger but still averaging 18.5mpg overall. If i went with a wider tire i feel this would be worse. Ps. BFGs run NARROW!! IMG_20160306_180540_zps6wyxbxwc.jpg

Edited by Patrick983
  • Like 4
Posted (edited)

after further evaluation....it looks like the rear is higher than the front.

 

85d4d8aa-2789-4dd8-92fc-073a25e1581e.jpg

This truck could have a level and blocks or extra leaf in the back. A quick inspection under the truck should let you know. I think this is important information for you to have prior to purchasing a used vehicle. If the previous owner did modify the suspension you want to ensure it was done properly followed with an alignment. If you don't know what to look for then have the vehicle inspected by an objective mechanic. You are paying hard earned dollars for this vehicle and a lot can happen in 7,000 miles! It could also mean you got a really great deal!

Edited by Donstar
Posted

This truck could have a level and blocks or extra leaf in the back. A quick inspection under the truck should let you know. I think this is important information for you to have prior to purchasing a used vehicle. If the previous owner did modify the suspension you want to ensure it was done properly followed with an alignment. If you don't know what to look for then have the vehicle inspected by an objective mechanic. You are paying hard earned dollars for this vehicle and a lot can happen in 7,000 miles! It could also mean you got a really great deal!

 

agree with donstar;

 

check for extra leaf, different shocks, any added blocks or spacers, and different UCAs....

Posted

Thanks, I will check it tomorrow. I'm buying from a wholesale dealer. Truck is a 1 owner with 7K miles, spotless. I appreciate the guidance gents! :seeya:

Posted

I installed a 2.25 inch pro comp.the rear is about an inch higher but it looks level.i also debadged and remove the front air dam .now it's time to save for tires and rims ..

Posted (edited)

2015 Silverado DC

5.3

3.08

Bilstein 5100 all four corner

(Set to highest setting up front)

BF Goodrich KO2 275/70/r18

80d02cc99b184b4757976f4fdd6926c8.jpgc4e9ddae2a7e92644519bfbcdca48414.jpg

 

Sent from my iPhone using Tapatalk

Edited by g.mando1
  • Like 1
Posted

Just leveled it this past weekend, much better!

 

RC 2.5" level upfront only.

 

 

what tire size and wheel specs?

Posted

what tire size and wheel specs?

Tires are Toyo open country AT ll

285/75r17 (says its 33.8")

Rims are Method Mesh 17x8.5 0 offset

 

 

Sent from my iPhone

Posted

I have a 2015 Sierra All Terrain, running a 2.5" Rough Country level and Toyo AT2 Xtreme 295/55r20 (33x12) tires on the factory 20" wheels. I know the factory AT and Denali wheels are both +27mm offset, it's stamped right in the back. I'm assuming the Chevy 20's are also the same. Saying the MAX tire size you can run is kind of irrelevant because a 305 Mud Terrain is going to be wider than a 305 Highway Terrain, and no brand is exactly the same size.

What I can tell you for sure, is on stock +27mm offset wheels you WILL rub the control arms with a 305/55r20 (33x12.5) wide tire. Everyone is always concerned about rubbing fender liners but that's plastic that can be easily manipulated. The control arms and sway bar are however a little less forgiving if you're rubbing up against them.

 

Here's some pictures of my truck:

 

20150212_164601_zpskmdv7pbs.jpg

 

20150208_100453_zpsrhdqxaee.jpg

 

20150207_212520_zpslsj03gez.jpg

 

20150207_212234_zpsd8dqtydw.jpg

 

You can see where the sidewall rubs the UCA and sway bar at full lock. I know of two other forum members with the exact same tire on factory 20's with the same issue so I know I'm not alone.

 

Seeing that the 295's rub, I guarantee the 305's will... It's the wheel offset thats killing it, many forum members are able to run the 305's with no clearance issues by simply running an aftermarket wheel with +12 or +18mm offset.

 

For sure you'll clear 275/60r20's (33x11), I've even heard of guys running 275/65r20's (34x11) but they might slightly rub the inner fender liner that can be zip-tied back. I'd be willing to bet that a 285/60r20 (33x11.5) wide tire would be the ideal size to clear the fenders and control arms, but pretty sure that size is only available in the Goodyear Duratrac's.

 

Another thing to consider if you care about fuel mileage is tire weight. Initially I thought I could fit 295's or 305's and only decided on the 295's because their 14lbs lighter per tire when comparing the 33x12 to the 33x12.5.

 

I'm going to try and add some 8mm front wheel spacers to simulate a +19 offset wheel and see if it's enough to push my tires out far enough to clear the UCA's.

 

Crawl under your truck and see what you're wheel offset is, it should actually say "20x9 +27mm Offset" or it might be one big number like "20x9JXIS27", either way knowing your offset is crucial to figuring out "what fits or not".

 

One of the best post in this entire thread!

 

BTW, I have those same style rims on my GMC Z71 but in 18". They are stamped 18x8.5 +24 offset. This is different from the +31 that a lot of posters will have your believe. Just crawl under your truck and shine a line on the backside of your spokes to see what the true factory offset is

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