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The Rear end "Clunk"

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Well started getting that rear end "clunk" on my 2012. Just under 39k miles. Not consistent, usually when going over a rough washboard road or turning into driveway. Ordered new sway bar bushings and end links. Going to add the little clamp blocks to keep sway bar from shifting side to side as I can see it has been shifting. I have the Ford Racing P springs, LCA's & mounts and Adj Track bar. Anyone else experience this?
 

cholmes1

400lb Gorilla
350
216
Denver, CO
I have a similar rear ‘clunk’ sound when setting off after the car has been parked and is exiting an uneven drive. Sometimes it is quite loud.

I always thought it was the parking brake sticking slightly, but your sway bar comments make a lot of sense. That said, my car has just 4800 miles so if the bushings are perished that would be a surprise.

I am interested to read your outcome as it will hopefully solve mine as well
 
Mine was a bad UCA bushing in the differential . Totally destroyed.....
I suspect they may be bad also. I'll check when the parts come in for the sway bar. I need to see if replacement LCA bushings for the Ford Racing LCA's are still available. The End Links took a while to find as parts suppliers only listed them for std GT 22mm. Boss has 24MM, 302R and GT500's have 25mm.
 
Can the bushing at the diff be replaced without removing the entire assenbly /body mount ? Seems like removing the arm bolt and lowering the rear to allow drilling out bushing rubber would work.
 
Last edited:
Can the bushing at the diff be replaced without removing the entire assenbly /body mount ? Seems like removing the arm bolt and lowering the rear to allow drilling out bushing rubber would work.
 
1,184
2,186
Exp. Type
Time Attack
Exp. Level
5-10 Years
SoCal
Can the bushing at the diff be replaced without removing the entire assenbly /body mount ? Seems like removing the arm bolt and lowering the rear to allow drilling out bushing rubber would work.
Yes, it’s serviced separately. They can be a major pain to get out. The OTC service tool, or some variation of press cups make this a breeze. I found the actual Rotunda/OTC cups used on eBay and just used 1/2” threaded rod with open lug nuts. The OTC threaded rod was crazy expensive.

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1,184
2,186
Exp. Type
Time Attack
Exp. Level
5-10 Years
SoCal
In searching various install videos that are about the entire aftermarket control arm and body mount they also show a bushing insert replacement that doesn't require the outer shell in the diff housing to be removed.

The old bushing inner shell is removed by 1/8"drill removing the old rubber. Then clean out the outer shell and install new 2 piece poly bushing. https://shop.redline360.com/product...kit-ford-mustang-shelby-gt500-2007-2014-en001 I'm thinking this can be done without having to remove the entire control arm assy.
 
I removed the wheels, both shocks, and the upper control arm from the differential only. this will let the rear differential drop enough for room to work. No need to remove the entire upper control arm. I used a ball joint press and some adapter cups to get the old bushing out. I put the new bushing in the freezer over night. It basically will fall in.
 

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