LCAs - replacement needed OR not??

How much lift can I add to my '89 Cherokee before I would have to replace the LCA's?

I was looking at the "Trailblazer" suspension systems offered by Rocky-Road [ http://www.rocky-road.com/xjtrailblazer.html ] (specifically the 4") and I noticed that it does not come with replacement LCA's. I emailed them and they said that it was not necessary and that all the other kits that do offer them just have them included as fluff !

What I really like about thier kits is the use of OME springs (full pack in rear) and a rear shackle. I've never read anything bad about OME springs and everything I've read here about longer shackles is a plus.

They do replace the Track bar with an adjustable one, it is not a secondary vendor unit but one that they manufacture. Is this sufficient or will I need to purchase the arms as an additional item?

My intent is to run a 31x10.50 mud and I am considering pretty much between this 4" kit and Rusty's 4.5" full rear pack, which appears to come with everything.

TIA

over 4" is the when you need replacement control arms. mainly adjustable ones for the pinion angles. Juice

On my 89 when I got to 3" I only had about 1" of droop untill the LCA hit the shock braket. Not very good for flex.

Pardon my ignorance with this , though I've owned this Cherokee since it was new it is only recently that I've started looking into modifying it.

Why don't you have to replace the UCA at the same time you replace the LCA?

Am I correct in saying that with this, or any, 4" lift: it might help to replace the LCA but it isn't that necessary to do so?


I know Mike.... I should do the Dakota spring set-up but times a wastin' and I like the idea of everything showing up at my front door

David - Atlanta said:

Why don't you have to replace the UCA at the same time you replace the LCA?

Am I correct in saying that with this, or any, 4" lift: it might help to replace the LCA but it isn't that necessary to do so?

Click to expand...

I'll see if I can explain what seems a bit intuitive to me in text, and then after I screw it up MaXJohnson can clarify it :

1) There are multiple reasons for replacing the control arms after a lift. One reason is that a lift shortens the wheelbase, and longer LCAs get some of that back. Second, as already mentioned a significant lift screws up both the pinion angle and the caster. While adjustable uppers and lowers are the ideal for adjusting all this, at 4" or so you can get things back in the ball park with just longer (not even adjustable, although they are better) lowers. Third, and also as already noted, the stock LCAs can only droop so far before they bind up. The better aftermarket LCAs, fixed or adjustable, are dog-legged to alleviate that.

2) I don't think it is correct to say that replacement LCAs might help at 4" of lift. I think it is fair to say that new LCAs definitely will help in several respects. However, they are not absolutely necessary. But that's like saying you can get a 3" lift with an AAL, but a full spring pack is better -- or you can address driveline vibes with a transfer case drop, but a SYE is better.

Personally, I would not lift 4" without replacing the LCAs.

David,

required reading before you lift!!!

http://members.aol.com/Stvns/XJhelp1.html

Three fantastic articles written by Ed Stevens

a lot of your questions will be answered here.

Thank you for the information, I will go ahead and replace them now since everything will already be apart (swapping in 4.10 axles at same time).

Eagle, you mention that the better ones are built with a dog-leg. Which are considered to be the better ones and are there any I should just avoid?

Has anyone recently purchased one of the Rocky-Road Trailblazer systems?

Go with the RE superflex arms if you do serious wheeling otherwise go with their superride arms.

I have the same OME spring set from rocky road. with Teraflex spacers and shackles. I only netted 3 1/4 up front and 3 1/2 in the back. I had to use a half-inch block in the back and two stock isolators to get to four inches. I used stock control arms for a year with this setup. I had front drive shaft vibes because of the pinion angle, and would just remove the front drive shaft when not going off road. To get full droop out of the front with 10 inch travel shocks, I clearanced the axle brackets and as for the track bar I redrilled the axle mount hole and also clearance the axle brkt. I now have both JKS control arms and track bar. With the pinion angle at zero to the drive shaft it has no vibes. as far as the control arms I like JKS and Rubicon Arms. They work on different principles, but effectively work the same for performance. The Rocky Road track bar does not have a lot of supporting data on the board as to its durability and function, but it is a lot less $.

The OME setup with shackles is on of the best flexing setups because of the soft spring rate and the flat arc of the leaf pack.

a far as on road performance The spring rate of the soft springs is more appropriate for a two inch lift. adding the extra height with spacers raises your Center of gravity and with the soft springs and shocks it has a little tippy feeling. A full length 4" lift coil spring with a little higher spring rate would give you a little firmer and less tippsy road ride

also remember--If you are going to use longer than stock front shocks, you are going to have to deal with the front brake hoses

give Dirk a call at DPGOFFROAD.com

He carries JKS OME and RE--very competitive prices. If you want to use OME springs in combination with other high quality components -- he is a good source to help piece a kit together.

lots to think about

Duane,
Did you purchase the OME springs from Rocky-Road as seperate pieces or in kit form? I'm thinking the two kits they are offering are something relatively new. I hadn't been to their website for a little while but I don't remember seeing them the last time I visited.

The trailblazer kit comes with new shocks (DTs I believe). In my email to them I asked about the brake lines, they said they have you retain the front lines but instruct on how to extend them and they supply a new rear line.

I purchased the springs as seperate items and added the teraflex spacers and shackles later ---$100 at sam's offroad. With the 10" DT shock you can get away with just unbenting the hard line and remounting it lower for the front brake lines. As I said before I ran the stock control arms and track bar for a year. The stock control arms are not good on the stock bushings because they don't allow for twisting, and they go south pretty quickly. Then it's time for new arms--good luck