I am planning on purchasing new tires (315/70/17) for my JKU. One tire shop said that an alignment would be needed afterwards. I can why an alignment would be necessary after adding a lift (change in geometry) but is it really necessary with just bigger tires? I just don't understand how that would alter the existing alignment. Are they just trying to separate me from 100 of my hard earned dollars?

 

Trying to steal you money. No need for an alignment

 

Of course they are trying to take your money. Tell them you are good without it.

 

Worth checking toe so you don't wear through your new meats. BUT.. Very easy to do yourself with a tape measure.

 

it's not needed, it's just easy to do if it's already on a lift.

if you are wearing your current tires evenly, driving strait, etc, then no, you do not need an alignment.

 

The point I could see is if you're going from stock size to 37's for instance. The front of the tire is now closer to the front of the Jeep which also means that you may now have more toe in, like 1/4" instead of 1/8" same with toe out for that matter. Think a triangle, the further you get from the base of the triangle the closer the lines come together The biggest reason I would do it is to insure those f'ing expensive tires last as long as possible. Generally they only set the toe so it shouldn't cost that much anyway I'll be getting new tires soon and planning a 1400 mile trip shortly after that, it would suck to wear away tire before I even get to use them off road

My from the peanut gallery

 

I am still trying to figure out why you would pay for an alignment on the JK. You can do it yourself (with the help of a friend) and get pretty close. You can't adjust camber and caster isn't adjustable unless you have aftermarket adjustable arms (we won't consider cam adjuster bolts cause they are bad).

You can check and adjust your toe pretty easily.

Is there a good reason to ever pay for an alignment on these? What am I missing? The Firestone lifetime alignment service seems like a good deal though!

 

^^^^^^

Do it yourself.

Project-JK.com - Jeep JK Wrangler Resource » Basic Do-it-Yourself Jeep JK Wrangler Front End Alignment

 

Not missing a thing, I forgot too mention it is easy to do yourself

I'm going to take mine in simply for a "where am I" on caster camber etc ..., that way when I do the toe & caster at home with my angle finder and tape measure I should have numbers that match thereby giving me a warm fuzzy on my numbers

 

Some people like the peace of mind. I think the free/cheap alignment checks are a good idea though. Out of spec camber numbers are a good thing to know about.