Pre-alignment question (one front tire worn on inside half)

[Twofish]

I'm working on my girlfriend's Jeep again.
When I took the rims off to have new tires mounted, the inside half of the front driver's side tire was heavily worn.
I was going to take it a shop to have it aligned but I was happy to learn that I can and should do it myself. I know my way around an engine fairly well but I don't have much experience with steering and suspension.
Before I begin, I just wanted to run one question past y'all.
Like I said, one front tire was worn on the inside half but the other tire looked to be wearing nice and evenly.
Does this indicate something is bent on one side of the vehicle or is this something that can be fixed with the toe adjustment?

About the Jeep:
The Jeep is a solar yellow 2002 TJ with just under 140k easy miles on the clock. My girlfriend is the original owner and it has never been in an accident. It had never even been shifted into 4wd until I came along and even then it was just to get through a bit of snow. It's had an easy life. She loves it though so I do what I can to take care of it for her. I just finished putting a new soft top on it, along with some new fender flares and fresh tires. I'm changing the oil in the motor, transfer case, transmission, and both differentials over the next couple days. I'd like to do the ball joints and whatnot but that's going to have to wait until I can put some more $$$ away.

 

[Chris]

One front wheel being worn could be something bent, bad ball joints, etc. It could also have something to do with improper tire pressure in that one tire, among other things.

 

[CharlesHS]

How does the Jeep steer when it's driven?
Are there any front end vibrations, hopping, cupping on the tire, grinding or does it pull in any direction?
I would check the ball joints for play, unit bearing for grinding, tire rod end for play, shock absorber for leakage and of course have the alignment checked.
There are numerous front end problems that can cause tire wear depending upon the type of wear.

 

[Goatman]

Generally on a solid axle there is no means to correct that type of wear pattern. As Chris said the options to deal with that would be either a bearing or ball joint. Otherwise it could be a bent spindle or axle. The only adjustments a straight axle can have is toe in setting and caster/pinion angle. With adjustable control arms the axle could be crooked to the frame, but that should not cause one side of the tire to wear excessively. Sorry. Inside tire wear is from that side of the tire leaning in. That's a camber adjustment that does not exist on a straight axle.

 

[Twofish]

I found some money in my pocket so I got some new hubs, ball joints, and tie rod ends. One side is just about wrapped up. Going to do the other side tomorrow.
Ball joints are really a joy to deal with. My knees, knuckles, and elbows are loving it.