Suspension Looks Line I Need New Rear Lower Control Arms

Chythar

Recently finished repairing my rear
Dirt-Old 20+Year Member
Aug 26, 2004
2,370
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Foothill Ranch, CA
Was driving home and heard a loud CLANK from outside the car. Wasn't sure if it was from the cars around me, but it became very clear it was from my GT as the clank repeated itself several times. I could FEEL the clank each time through the seat. Fortunately, I was nearly home (and off the freeway) so I babied it into my parking spot. A quick check under the car told me the problem - can you see it?

damaged_lca.jpg


These are used HPM Mega-Byte Jr's I bought and powder coated years ago. Looks like there was rust inside the arms as well, which weakened them from the inside out until the rear sway bar mount just tore itself off. I do not consider this safe to drive with, even if I remove the sway bar. So the GT sits until I get replacement LCA's. Any recommendations? I really liked how the Mega-Byte Jr's repositioned the pivot point of the rear axle, which eliminated the rear squat. Is there anything on the market that does something similar? This is a street car only, no autocross or drag racing in the foreseeable future. I'm not too concerned about a harsh ride, and I'm fine with squeaky polyurethane bushings. Greaseable bushings would be a big plus.
 
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Really happy with my Maximum Motorsport LCAs. Seem to be well constructed, definitely tightened up the rear end, but that's comparing them to the stockers that I replaced. I've been happy with everything I've gotten from MM, including the CC plates, subframes...
 
By sheer luck a brand-new never installed set of Mega-Byte Jr's showed up on the Corral, which I purchased for $200. Once these are installed, I'm back on the road.
 
Sorry to see that Matt. Nice pick up on the new parts though. :banana:

How did those get so much rust? Did they come from another part of the country?
 
I bought them used some years ago, not sure if it was eBay or the Corral. They certainly spent several years in snow/salt before I got them. I had them sandblasted & powdercoated to take care of the outside issues, but apparently the inside was just as bad. I do not remember exactly how long I've had them, at least 6 years or so.
 
Wow, that's some rust. I've seen Chinese control arms shear like that. Wouldn't expect that from HPM though. MM, TeamZ, Steeda would be the ones I'd purchase.

Well, I bought the LCA's used and they had clearly seen a lot of salt & snow. I would have to guess that the Mustang they were on had been driven often in the winter, most likely several winters. I can only guess that some salt got inside the arms. Each of the LCA's has drain holes in them, so it is possible that salt got in the arms and started eating them away from the inside.

It's entirely possible that the previous owner of the LCA's had already damaged them but the damage wasn't visible. It probably wouldn't have taken more than a small crack near the sway bar mount to start the cancer you see there. I see rust on the edge of the sway bar mount, where it broke loose from the LCA. That metal has been bare for a while.
 
Got my new Mega-Byte Jr's in today. Tapped them for zerk fittings while I had the opportunity, always nice to have greasable joints. First pic is of the new arms, drilling holes for the zerk fittings. Gotta love bachelorhood, I can do this work in the kitchen. XD As you can likely see, these LCA's are brand-new and never installed. What's interesting is the sway bar brackets have "HPM" cut into them. My old set doesn't have that.

The Mobil 1 is for the tap there in the lower right, always good to oil up the tap to cut down on the friction. You are cutting metal after all.

mega_byte_1.jpg


Next up is tapping one of the holes for the zerk fitting. All the marks on the LCA are just smudges that caught the light wrong.

mega_byte_2.jpg


Last is the arms with zerk fittings and assembled, almost ready to install. This set was missing two poly bushings (which I knew about when I bought them) but I can take two good bushings from the currently installed LCA's. The red pieces on the zerk fittings are dust caps, they just snap on.

mega_byte_3.jpg


I'll be installing these tomorrow (Saturday), so I'll be able to take better pictures of the damaged LCA.
 
You really should drill a hole all the way through the bushing from the grease fitting. The point is to get the grease from the exterior radius all the way down to the pin.

Kurt
 
You really should drill a hole all the way through the bushing from the grease fitting. The point is to get the grease from the exterior radius all the way down to the pin.

Kurt

Agreed, but what you can't see is that the bushing actually leave a gap in the middle - they aren't long enough to touch on the inside. The bushings also have tiny reliefs cut in them so the grease gets from the center to the outside. Basically, you are right and it's already taken care of.
 
You really should drill a hole all the way through the bushing from the grease fitting. The point is to get the grease from the exterior radius all the way down to the pin.

Kurt

Took a couple of pictures that may give you an idea. These are from the old Mega-Byte Jr's I just removed. The ridge of grease in both pictures should give you an idea how much of a gap there is between the bushings. When I grease the bushings, I work the hand pump until I see grease coming out from one side.

mega_byte_6.jpg


mega_byte_7.jpg
 
Got the new LCA's installed today, though I wasn't able to finish since I ran out of suspension grease just as the local auto parts store closed. :( I'll finish up tomorrow. First photo is the new LCA next to the broken one. I noticed that the welds around the sway bar bracket were thicker and there were more of them, perhaps the bracket breaking off was a known problem?

mega_byte_4.jpg


Next photo is a close look at the damage. There really isn't a lot of rust inside, more like light surface rust. I don't think the bracket broke off due to rust on the inside of the LCA now, it looks more like metal fatigue.

mega_byte_5.jpg