If you're carrying a spare tire all that weight is transferred to the passenger side as well. For a 40" I would imagine that's quite a bit.
Mine leans as well, got worse when I went with a 130 pound 37" tire/wheel combo.

 

The spare tire is in the center, though.
It would become an increasing factor only as the tail gate is swung toward fully opened.
If there is an aftermarket swing-out tire carrier, its weight would be to the passenger's side, but the weight of the tire is still in the center.

 

It hinges on the right which is where the weight is transferred, even when closed.


EDIT: here's a snip from Teraflex commenting on the lean.

 

I disagree in regards to the spare. If the spare is centered it's weight is felt by the suspension over the center regardless of where the carrier is mounted to the frame.

I run no spare and had the lean. Used a 1/2" higher front coil spacer on the passenger side and it's fixed.

 

All I know is that the lean is worse when I have a full tank of gas and not as bad when the tank is almost empty.

 

Mine leans to the right as well. Only about 1/2" lower on the passengers side.

I think it has something to do with the fact that the engine torque pushes the passenger side down. You can really notice how this works when you are in 4 low and you give it a little gas and hold the brake on. The engine tries to turn the drive shaft which tries to turn the axle. The springs are the only thing keeping the axle from spinning like a propeller. The torque of the engine is always trying to compress the passenger side springs and extend the drivers side springs. If you did the same test in reverse gear, you would get the exact opposite response. The driver side would be pushed down and the passenger side would come up.

So in my case, since I have an automatic and pull into my garage forwards, the passenger side is always just a little more compressed. Then when the engine is turned off and foot taken off the brake, the pressure in the drive train is released letting the passenger side come up a little. However it never comes all the way back up to where it would be if you had backed into the same parking spot.

This is my own home grown theory. It lets me sleep at night without dreaming of coilovers that would let me fix the problem once and for all. I will cling to this theory so long as my Jeep leans. I take comfort in the fact that others have jeeps that lean and that we all seem to lean the same direction. Acceptance of the lean is the first step to inner peace.

 

post deleted.

Sorry, I was being a JA..

 

It's a common misconception that the center of mass is transferred to the support point. In reality, it isn't.
I was hoping you would take from my post that it doesn't matter that the hinge is on the right. What matters is the spare is in the center. That's just the physical nature of it.
Even if it did matter, when the tail gate is closed, it is also supported by the latch. So where is the weight transfer then?

Regarding the quote from Teraflex, it doesn't account for the fact that not all JKs lean to the right. Mine doesn't by measure, and when I weighed it, it was nearly equal left and right. The Tereflex rep who wrote that the spare tire's weight (center of mass) is transferred to the passengers side through the hinge just doesn't understand what is actually going on.
Yes, the tank is on the right. There is lots of equipment on the left that isn't on the right. Why single out the gas tank?

 

You know mine leans as well, but I just adjusted the shocks on the passenger side a little stiffer. Thought of switching driver to passenger?

 

bringing back an old thread but did you use the spacers on both front and rear or just rear?