Lower Control Arms - TJ Lifts

WillysGuy did pass the time by typing:

The longer lower arms keep the geometry right. It's not the angle of the arms it's the curve your axle sweeps through as it travels and how close it moves to the xfr case. With the larger liftkits you need longer lower arms or under full extension your driveshaft might get stuffed into the case. That and the alignment between diff and xfr case gets off.

Now your at least as confused as I am.

Yes, you should at least get the lower arms. This will enable you to 'clock' or rotate the diff. to bring the driveshaft into proper position or alignment. The control arms are adjustable so you can make them various lengths. For instance, as you shorten the lower rear control arms, the pinion starts to point upward. If you lengthen them, the pinion starts to point downward.

If you lift 3", you will quite probably need a CV driveshaft to eliminate driveline vibrations caused by the lift. If you have a CV driveshaft, you will need to point the pinion up higher than the stock control arms will allow, necessitating the adjustable arms. Also, budget in an SYE kit if this is not a Rubicon.

If you take a stock TJ and try to stuff 3" taller springs into it and nothing else, you will not be happy, and neither will your TJ. Best bet is to buy a complete kit when you get into the 3" or higher range.

JMHO.

WillysGuy wrote:

Lower arms are for wheelbase, upper arms are for pinion angle. n.

On the same subject... As a possible future TJ owner, how about a 2" coil only lift? Are lower arms required? Would that be good for 32" tires?

-- JimG

80' CJ-7, 258 CID 35" BFG MT's on 15x10 Centerlines 4.56 D30-D44 SOA D300 w/4:1 & Currie twin sticks Warn 8000i w/dual batteries LockRight F&R

Jim, I noticed you have the Lock Right's in your Jeep. What is your opinion on the locker in the front? I have one in my 2wd S10 pickup that is a street/strip type vehicle, and it's great for dry pavement traction, but I feel it doesn't "unlock" easy enough when going around corners. I've had the truck do a complete 360 on me on a wet road which caused me to have a seat cover surgically removed, if you know what I mean. I haven't found a Jeep here yet, but I was considering using the Lock Right, at least for the rear. My concern here is that I will have to drive this thing in the winter, and I don't want it acting like my S10 does. From what I've read here, I think the best setup might be a Lock Right in the rear and an air locker in the front, but would like opinions.

Chris

Hi Chris,

A front locker is a must-have for the wheelin' that I do... but can be tricky in the shallow snow/ice. For shallow snow or ice I will sometimes unlock one of the front hubs... that helps. For binding, I have the twin sticks to disengage the front for sharp turns on the trail.

Mine will only unlock if not accelerating in a turn... it then ratchets nicely. I purposely let off the gas in turns so it will ratchet.... if I don't it will sometimes build up and then pop loudly ("have a seat cover surgically removed"). You definitely have to adjust your driving technique with lockers on pavement. I find myself shifting gears as smoothly as possible.... ease into the gas and don't accelerate in turns.

Not sure what the advantage would be over twin sticks (assumes 300 transfer case). The twin sticks are much less expensive!

JimG