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Big Height Difference Front and Rear AT4

Nick__
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Nick__ Enthusiast

Nick__

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Posted (edited)

Hi guys. New member here. I'm fresh from the introduction area. 😀  But I did have a question I couldn't find the answer to. My 2021 AT4 is a full 3 inches higher in the rear than it is in the front. That seems excessive. I only know this because I was measuring to see what kind of leveling kit to purchase. Anyone with a similar experience?

Edited by Nick__
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AD80
AD80

They say the u bolts should be changed because the threads are stretched when they are tightened or something like that. Most folks use the same bolts without problems, but you may want to change them

Transient
Transient

Hook up a trailer.  Problem solved.

richmz
richmz

It's important to know what you're measurement reference is. Are you measuring from..   Top of tire to center of wheel well?   Ground to bumper?   Ground to frame?

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richmz Enthusiast

richmz

Posted
Posted (edited)

It's important to know what you're measurement reference is.

Are you measuring from..

 

Top of tire to center of wheel well?

 

Ground to bumper?

 

Ground to frame?

 

Most pickups are higher at rear by design so that when loaded it will distribute the weight properly.

 

Here is a '21 GM AT4 file photo. The rear rake is noticeable, probably about what you're seeing.

spacer.png

 

Last year I took some photos of mine on level ground when loaded with over 20 bags of bark mulch. I was impressed with it's stance with it loaded, likely around 1,000 lbs or more. It handled fine at speed too.

 

 

AT4_053.jpg

AT4_051.jpg

AT4_052.jpg

Edited by richmz
  • Like 1
RCF71 Enthusiast

RCF71

Posted
Posted
10 hours ago, Grover67 said:

My '20 AT4 is 2" difference stock height

 

 


Same here.

newdude Senior Enthusiast

newdude

Posted
Posted (edited)
22 hours ago, Nick__ said:

Hi guys. New member here. I'm fresh from the introduction area. 😀  But I did have a question I couldn't find the answer to. My 2021 AT4 is a full 3 inches higher in the rear than it is in the front. That seems excessive. I only know this because I was measuring to see what kind of leveling kit to purchase. Anyone with a similar experience?

 

 

Are you measuring from the ground?

 

Most of the times rake is measured from the center of the wheel to the bottom of the wheel well.  Using this point, 1500's run right at about 2" front to rear difference, HD trucks run about 3".    

 

Also.  Leveling an AT4, you MUST get new upper control arms or you WILL have ball joint failure.  

 

 

Edited by newdude
Kilgore Trout Enthusiast

Kilgore Trout

Posted
Posted

I measured mine this morning (bone stock for AT4 specs), 3" of rake, measured at the center of the wheels, ground to lower lip of wheel well.

 

It looks level, perhaps an optical illusion with that big old honking grill...

 

But clearly is ready for a real level.  :)

AD80 Enthusiast

AD80

Posted
Posted

You could always remove the rear block. That should get you level without changing you front end angles. Since it is already raise 2”

front and rear from the factory, if you remove the rear block, it should sit the same as a non at4 with a front level kit. So it won’t look too low if that’s what your thinking.

  • Like 1
Kilgore Trout Enthusiast

Kilgore Trout

Posted
Posted
7 hours ago, AD80 said:

You could always remove the rear block. That should get you level without changing you front end angles. Since it is already raise 2”

front and rear from the factory, if you remove the rear block, it should sit the same as a non at4 with a front level kit. So it won’t look too low if that’s what your thinking.

I just installed some of those fancy AMP Research power steps, so I am thinking higher... 😉

nolimits76 Enthusiast

nolimits76

Posted
Posted
On 11/13/2021 at 7:27 AM, newdude said:

 Also.  Leveling an AT4, you MUST get new upper control arms or you WILL have ball joint failure.  

 

 


Also new here. Wasn’t aware of this. What brand and model number is recommended?

Nick__ Enthusiast

Nick__

Posted
  • Author
Posted
On 11/13/2021 at 7:27 AM, newdude said:

 

 

Are you measuring from the ground?

 

Most of the times rake is measured from the center of the wheel to the bottom of the wheel well.  Using this point, 1500's run right at about 2" front to rear difference, HD trucks run about 3".    

 

Also.  Leveling an AT4, you MUST get new upper control arms or you WILL have ball joint failure.  

 

 

Yes, I was measuring from the ground. I'll try measuring from the top of the tire. I wasn't aware that was the correct way. Thanks for the heads up!

Nick__ Enthusiast

Nick__

Posted
  • Author
Posted
On 11/13/2021 at 6:23 AM, richmz said:

It's important to know what you're measurement reference is.

Are you measuring from..

 

Top of tire to center of wheel well?

 

Ground to bumper?

 

Ground to frame?

 

Most pickups are higher at rear by design so that when loaded it will distribute the weight properly.

 

Here is a '21 GM AT4 file photo. The rear rake is noticeable, probably about what you're seeing.

spacer.png

 

Last year I took some photos of mine on level ground when loaded with over 20 bags of bark mulch. I was impressed with it's stance with it loaded, likely around 1,000 lbs or more. It handled fine at speed too.

 

 

AT4_053.jpg

AT4_051.jpg

AT4_052.jpg

Measuring from the ground to bottom of wheel well. Thanks for the info.

Nick__ Enthusiast

Nick__

Posted
  • Author
Posted
On 11/14/2021 at 1:20 AM, AD80 said:

You could always remove the rear block. That should get you level without changing you front end angles. Since it is already raise 2”

front and rear from the factory, if you remove the rear block, it should sit the same as a non at4 with a front level kit. So it won’t look too low if that’s what your thinking.

Interesting idea. I actually was wondering about this. Seems like it's a good way to get a safer level for less money on the AT4. But then it would sit a little lower than a front "lifted" AT4. Maybe not a bad thing?

Nick__ Enthusiast

Nick__

Posted
  • Author
Posted
On 11/14/2021 at 1:20 AM, AD80 said:

You could always remove the rear block. That should get you level without changing you front end angles. Since it is already raise 2”

front and rear from the factory, if you remove the rear block, it should sit the same as a non at4 with a front level kit. So it won’t look too low if that’s what your thinking.

Do you think it would be better to lower the rear with lowering shackles, or removing the rear block?

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