I did a TF 2.5 coil lift on my JK unlimited. I still have the stock control arms and I think it drives fine. Maybe a little touchier on the highway but nothing to get too worked up about.

 

At 2.5" of lift your Jk will have about 2.9 to 3.1 deg of castor, so probably a touch to low. And if you think your Jk drives OK at this height and this amount of castor, that is probably becasue you are use to is. if you install LCA's and adjust castor back to 4.5 or to 6 as some do, there is a noticeable improvement in its flighty steering. I have had my arms in and out a few times trying to solve wobble issues, and there is a noticable difference. Some suggest that low castor can help induce a wobble, i am not sure what low is, but i reckon at 3 deg, you are getting close to it. WOL - the toe does change when castor changes, can't really explain why but it does.

 

When I put my 2.5 in teraflex coil lift, adjustible f/trac bar on I drove it for it for about a month with out any steering problems (flightyness). It felt like it drove like it did before the lift. I then put my lca arms on setting the lenghts at 23 in. dr side and 23 1/8 for pass. side. I then felt a slight pull to the right while driving. I took it to have an alignment done. I was told that everything was perfect except the toe needed to be turned in and they set my steering wheel straight. They said my caster is at 4.2 degrees. Now it drives great. But I was wondering....if I want to add a 1 in. spacer front and rear will I have to get the alignment done again? the reason I ask is they told me that I can come back again within 6 months to have it checked-adjusted again. I wish I went with the 3 in. lift...

 

Yes, your caster will change. No, you won't 'have' to get a new alignment, but if they are offering to do it for free, why not get it?

You can also do it yourself...
http://project-jk.com/jeep-jk-write-...-end-alignment

 

You need a new frame and axle guy. The JK's have zero caster and camber adjustments from the factory.

To get any caster adjustment, you need to buy a slot kit or adjustable control arms.

To get any camber adjustment, you need to buy offset ball joints.

In stock form, you can only adjust toe in and center the steering wheel.

As you go up in lift, the caster angle decreases. Camber does not change. Caster affects how well the vehicle tracks straight and affects the vehicles highway drivability. Less caster allows the vehicle to drift more and it feels more "flighty" at high speeds.

The lift does not "take away" any adjustability as he claims.

 

That would depend on the camber angle. The toe would change more with a lot of camber, it would change less with less camber. With zero camber, toe will not change.

 

I (with help) installed a 4" TF Flexarm kit this weekend. I just took my 2010 Jeep Unlimited automatic to the alignment shop. He told me it was all out of shape and it would take a minimum of 4 hours (330 dollars) to get everything correct. Does this sound over the top? I don't know ANYTHING about this. ANY help is great.

 

i guess it all depends on how you installed everything. if you followed my write-up, your alignment should be set correctly:

http://project-jk.com/jeep-jk-write-...ation-write-up

toe doesn't change so nothing has to be adjusted there. assuming both your lower control arms are set to equal lengths and you set your adjustable front track bar as needed, your axle should be in the correct position. and, so long as you remembered to center your steering wheel, there shouldn't be anything you need to do with it. AT MOST, the only thing that may need to be set is your caster and i hardly think that's worth $300+ to do especially when you can easily do it yourself:

http://project-jk.com/jeep-jk-write-...-end-alignment

 

I'm glad I live in my small town. Did a lift on my rig last week, and took it in for an alignment today and all they needed to do was fix my toe-in and that cost $35. The full alignment would have been $60. All it took was 20 min.

$330. Sheesh.

 

I have four inches of lift on my JK and my caster is in need of being adjusted.

My front driveshaft is also going out and I will replace both at the same time to ensure that the new driveshaft is set correctly with my new lower LCAs. And, of course it will be done in my garage, the right way.