HD UCA's

[Phunkeydude]

I highly recommend these. They held up to some serious abuse on the trails when I trail tested the prototypes. Doc is correct...I chose the design to have a heim joint so there would end up being more travel than a ball joint and being an expert at ripping apart ball joints, I never wanted to deal with that again on a trail ride.

[07JeepXK]

I highly recommend these. They held up to some serious abuse on the trails when I trail tested the prototypes. Doc is correct...I chose the design to have a heim joint so there would end up being more travel than a ball joint and being an expert at ripping apart ball joints, I never wanted to deal with that again on a trail ride.

When you had yours did they make all kinds of squeeking noises? I heard a few members with them had that problem.

[wahoowahgator]

I am on the fence also,
couple of questions;
Where can you get spare helm joints?
Did you have any problems with getting an alignment?

[bruijr]

These HD UCA's don't have heim joints. Heim Joints are spherical bearings with an integrated rod end. That's why heim joints are regularly also called "rod ends" . The bearings used are plain spherical bearings with a PTFE liner. This means that there is a teflon coated fabric in between the housing and the ball. No lubrication is required for this bearing and they are very easy to replace. These bearings are for sale all over the internet at several offroad racing stores. I have located a manufacturer and thru their distrubutor I can get the bearings and missalignments bushings. Also the poly spacers, bushings and pins can be replaced. I can get these from HM Engineering at any time. In short, all parts can be replaced and I can get those at any time.

I still have to install the UCA's on my XK but what I know from other members who has them, the alignment is not an issue. Best is to install the UCA's together with a lift so you do the alignment at one time. Since most of the members already have the lift installed you'll might have to get an extra alignment performed. This you also have to do if you install other upgrade UCA's.

Tom, did you do a new alignment on your XK once you had installed these?

[07JeepXK]

So basically both units are totally rebuildable, the only difference is one uses a normal spicer ball joint and one uses a uni-ball.

[bruijr]

So basically both units are totally rebuildable, the only difference is one uses a normal spicer ball joint and one uses a uni-ball.

Correct.

The result of this difference is that the HD UCA's from HM Engineering can be used for every lift available. The UCA's with the spicer ball joint can only be used with a lift for were the UCA's angle is corrected for.

This is a statement placed on an other forum on the exact same UCA's:

"Poly bushing are overated IMHO. First off they are the same bushing that are in your stock arms, which means wide availability.
Secondly they take out some road impact and don't require special grease like most poly bushings do.

Right now these are based a 2.5" lift geometry (over stock). This pretty much covers everyone except for the 4" Superlift (and equivalent) guys, since they are designed to run stock geometry arms.

Those as well as ones for stock/lowered WK/XK's will be on there way".

In other words stock / 4" lift require a different set of arms than the 2" lift. This is only because of the limited travel of the spicer ball joint.
Also, the poly bushings might be overrated but I do have read in several threads (on other forums) that the UCA bushings are worn / damaged on XK's and WK's. IMHO, better overrated. This means that they are probably don't have to be replaced at all.

Since the HM Engineering UCA's are designed with desert racing /experience in mind they might be overrated. Personally, I don't mind that at all, especially not on a critical part like this one.

[07JeepXK]

My main concern is alignment issues. I'm about to spend another grand on a new set of tires and hate to have the outter treads wear like the last set due to not being able to align it properly.