GREGGPENN

I had my local shop rehab the suspension last week. I ordered black Energy Suspension bushings, AC Delco ball joints/Tie Rods, and Timken wheel hubs.

Because I'm friends with the manager, he let me polish the front alum while disassembled. He took it apart on Friday. I brought the pieces home, cleaned and polished over the weekend. He reassembled on Monday.

After reassembly, the DS suspension "pops" when bounced. They suspect a bushing but aren't sure.

When I brought the parts home, the lower CA bushings where already pressed in. Beyond that, the old ball joints and upper bushings were still mounted.

I started cleaning the parts by hand but realized I didn't have enough time/patience to get the task accomplished over one weekend. I pulled out my power washer, set the stream to narrow, and blasted the modest layer of "gunk" off the control arms and steering knuckles. After two hours, I switched to steel wool and aluminum wad polish. Finally, I hit all the parts with 2k rpm alum polish with cotton buff (wheel).

I was a bit concerned about water blasting and cleaning the parts having the lower bushings in place. But, they are ultra firm. Even with water blasted around their perimeter, it doesn't seem likely that water/debris would penetrate their perimeter...and get between the bushing and control arm.

OTOH, I wonder if anything would have gotten between the bushing and inner metal insert? Plus, w/o doing the actual install, I don't know if the lower CA rotates on that insert OR if the insert rotates in the bushing?

Point is, the shop is trying to isolate what is causing the pop. They aren't even convinced it has ANYTHING to do with the lower CA bushings being installed during my cleaning/polishing "phase".

When they bounce the front end, it simply pops. They said it almost sounds like a poly bushing is rotating/jumping in it's "receptacle". They don't think it's a ball joint.

What are your thoughts? Anyone had this happen after rehab?

LTxDave

Make sure they greased the ball joints. Also make sure they lubed the poly bushings.

pkincy

Forgive my memory as it is been a while since I did a lot of suspension work on a race car, but the state of the suspension when the CAs are retorqued can make a huge difference.

This sounds like the CAs were torqued in Droop rather than in Suspension. So you may have some suspension preload.

Tom400CFI

Not when you use aftermarket poly bushings. The bushing should slide/pivot on the steel spacer that the bold goes through. As previously mentioned, it should be greased so that it can pivot smoothly and w/o much effort.

Not the same as OEM rubber bushings which DO need to be tq'ed at ride height.

GREGGPENN

Because of the great pricing for rehab, there is no pressure [on the shop] to redo/diagnose. But, they are convinced the upper CA on the DS is what's popping. They are also convinced it's not bent/damaged because it aligned -- though they sent it out to a machine shop to have the bushings pressed out/in.


I picked up another packet of Energy Suspension lube to redo the lube job. The machine shop SAYS they lubed the bushings before pressing them in. (Seems like they would ... to make it easier to insert. OTOH, maybe they didn't lube the metal inserts?)


I'll find out soon, I think. Maybe I'll actually get to drive it again before the long, hard, cold, snowy, SOB winter sets in! Guess we dodged the big snow last weekend!

Midnight 85

I'm betting the re-lube will cure it. Those poly bushings if not well lubed will "stick" to the surface they sit in, then when you move the suspension enough they pop when they become unstuck. I had a similar issue on the rear dogbones.

GREGGPENN

I hope that will be it too. I just emailed the shop to ask about their position IF the opposite side starts making noise next spring/summer. If the machine shop didn't properly lube one side....could the other be "scarce"?


We'll see what they say.


I'm also still debating the installation of trailing arms with heim joints -- as sold by a couple of vendors. I'm anxious to see what the overall change/improvement is in the front. If that noticeable, it sounds like a more freely articulating rear could also impress me. Brian Cunningham seems convinced that I would notice a huge improvement by converting those dogbones.

cv67

Have the same issue in my A body or had with a worn out suspension
Only when backing up wiht the wheel turned

New suspension (polygrahite) cured it....for 200 ni now it does it again
Probably the A arm bolt shifting around Im guessing nothings cracked or broken

Wonder if you got somethign slightly bound up thats shifting shouldnt hurt anything. Check carefully. If all is well drive it.

Midnight 85

I am happy with my heim joint dogbones as far as performance goes but I was told they would not knock when driving the car but in town they are noisy. On the road I rarely hear anything from them. I guess if you can stand the knocking coming from them then I'd say go for it.

JrRifleCoach

Need to ensure the bolts are pivoting in the bushing.
Not binding and causing the bushing to rotate in the housing.
Or the combination may be causing the noise.

You can check by backing off the torque on all the pivot bolts.
Then test bounce. Maybe start torquing each bolt until the noise returns.

Good Luck