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2020 AT4 Mod Additions Step by Step

NolaHorn

By NolaHorn
in Modifications, Wheels & Tires

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NolaHorn Enthusiast

NolaHorn

Posted
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I purchased a 2020 AT4 a few weeks ago and have had the dealer make a number of modifications after much research on this site.  Due to Covid19 some of the parts have been slow to arrive and the dealership has been sending me pictures as each modification has been made.  I figured this would be a good place to share those pictures and help out with someone who may be looking to do similar mods to show what worked and what didn't.  We are still having trouble with rubbing and are changing out the wheels, so this isn't complete just yet but I hope to take delivery of the truck next week and will post final pictures when I get it.

 

Here is a list of the original mods ordered:

Fuel Contra 20" x 10" (-19) Gloss Black Wheels

   (Changing to 20" x 9" (+2) due to rubbing)

Nitto Ridge Grapplers 305/55R20 Tires

Ready Lift SST 2" Level Kit

Westin HDX Wheel to Wheel Drop Steps

GMC Cold Air Intake

GMC Performance Exhaust

GMC Window Deflectors

GMC Rugged Look Fender Flares (Painted)

GMC Tonneau Cover

NolaHorn Enthusiast

NolaHorn

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Rubbing on Flares with 10" wheels with (-19) offset.  Attempted an alignment and some trimming of the flares.  Still rubbed.  Tried 285/60R20 tires and still rubbed.

IMG_5414.JPG

IMG_5415.JPG

aragrev7 Enthusiast

aragrev7

Posted
Posted

Very nice!
I’m new to the lifting scene. My previous vehicles were Japanese imports, so We always when the other direction.

The leveling kit, what’s the benefit for you? Our AT4’s have a 2” at least lift I know.
The back end is up a bit to compensate for load (?).
I can do research on it too, but I prefer conversation : ) I keep seeing it, just forget to look into it on breaks.


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NolaHorn Enthusiast

NolaHorn

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Here's a pic of the truck with the 285/60R20 tires installed.  Waiting on the 20x9 wheels with less offset and will try the 305's again.

IMG_5425.jpg

NolaHorn Enthusiast

NolaHorn

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3 minutes ago, aragrev7 said:

Very nice!
I’m new to the lifting scene. My previous vehicles were Japanese imports, so We always when the other direction.

The leveling kit, what’s the benefit for you? Our AT4’s have a 2” at least lift I know.
The back end is up a bit to compensate for load (?).
I can do research on it too, but I prefer conversation : ) I keep seeing it, just forget to look into it on breaks.


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The leveling kit lifts the front end two additional inches and replaces the 2" block in the rear with a 3" block.  According to ReadyLift it will allow for 305/55R20 tires on 9" zero offset wheels.  The parts manager felt we should try the 10" wheels with -19 offset to bring the tires out and fill the wheel well under the fender flares.  Turns out the extra offset caused the rubbing.  Hopefully the 9" wheels with +2 offset will bring the tires in enough to clear the fender flares.

aragrev7 Enthusiast

aragrev7

Posted
Posted
The leveling kit lifts the front end two additional inches and replaces the 2" block in the rear with a 3" block.  According to ReadyLift it will allow for 305/55R20 tires on 9" zero offset wheels.  The parts manager felt we should try the 10" wheels with -19 offset to bring the tires out and fill the wheel well under the fender flares.  Turns out the extra offset caused the rubbing.  Hopefully the 9" wheels with +2 offset will bring the tires in enough to clear the fender flares.

Ahh that makes sense. My next big step is for wheels. I also wanted to get a bit more beef under there, maybe widen the stance a bit with some negative offset, but it seems you ran into a bit of trouble that direction on a 10” wheel.


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  • 2 weeks later...
NolaHorn Enthusiast

NolaHorn

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Finally got around to taking pictures once I brought the truck home.  Here she is with the 9" (+2) wheels and 305/55R20 tires.  Very happy with how everything turned out.

 

IMG_5437b.thumb.jpg.442b6e9ce19464c248c606712661a0c3.jpg

 

EZ Money Enthusiast

EZ Money

Posted
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I am planning on running the 2" SST kit with a set of 22x10 Hostile Sproket.  The wheel has a -25 offset.  We are going to use a 295/55/22.  It might rub a little, but can do some trimming.

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