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Discussion Starter · #1 ·
Anyone know the size of the nuts & bolts in the front and rear lower control arms? I'd like to replace the stock hardware with grade 8 (order through McMaster Carr) but am not sure of the size.

Thanks!

PS - New Rokmen adjustable front and rear lowers will be installed this weekend. I'll take pics and post for those interested.
 

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Rear:
14x2.0x90
Front:
Frame end 14x1.5x100
Axle end (eccentric) 14x2.0x111
 

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Bolts

Try 9/16 x 4" with a 3" shank. PPM sell them as a kit.
14mm allow to much play in the chassis holes and also the bushes.

Anyone know the size of the nuts & bolts in the front and rear lower control arms? I'd like to replace the stock hardware with grade 8 (order through McMaster Carr) but am not sure of the size.

Thanks!

PS - New Rokmen adjustable front and rear lowers will be installed this weekend. I'll take pics and post for those interested.
 

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Try 9/16 x 4" with a 3" shank. PPM sell them as a kit.
14mm allow to much play in the chassis holes and also the bushes.
There are two issues. First, the holes in the brackets and bushings are 9/16", not 14mm. The 14mm bolts the factory uses are just a bit smaller permit slop & movement. Second, the factory uses standard (fully threaded) bolts, not shouldered bolts. The threads work on the bushing sleeves & bracket holes like a rat tail file, eventually making them larger and the fit sloppier. You can either get the Poly Performance bolt kit, or just run down to your local Ace Hardware or True Value store's bolt bins and get some 9/16" grade 8 shouldered bolts, washers and Keps nuts & be done with the problem. Replace the four on the track bars, too while you're at it.
 

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Discussion Starter · #7 ·
There are two issues. First, the holes in the brackets and bushings are 9/16", not 14mm. The 14mm bolts the factory uses are just a bit smaller permit slop & movement. Second, the factory uses standard (fully threaded) bolts, not shouldered bolts. The threads work on the bushing sleeves & bracket holes like a rat tail file, eventually making them larger and the fit sloppier. You can either get the Poly Performance bolt kit, or just run down to your local Ace Hardware or True Value store's bolt bins and get some 9/16" grade 8 shouldered bolts, washers and Keps nuts & be done with the problem. Replace the four on the track bars, too while you're at it.

Thanks guys.

Discovered the 10.9 issue on McMaster Carr. I'll check out the Poly Performance kit as well as the local Ace bins to see if they have anything large enough.

My concern, with the stock bolts, is their ability to take my cranking to 130-ft/lbs. When I did the rears, I kept thinking, "It's gonna snap...I know it's gonna snap...". This happened on my TJ track bar bolt.
 

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My concern, with the stock bolts, is their ability to take my cranking to 130-ft/lbs. When I did the rears, I kept thinking, "It's gonna snap...I know it's gonna snap...". This happened on my TJ track bar bolt.
I know how you feel. I snapped one of my front CA moutning bolts after replacing a bushing. And I am by no means a big guy. I've thought about replacing all with grade 8's as well, but as of now only have the one. Unfortunately, I don't remember the size I ended up with from Lowes. Just brought the busted one in and found something similar. I do remember the fit was a bit tight and at one point just needed a little persuasion.
 

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Thanks guys.

Discovered the 10.9 issue on McMaster Carr. I'll check out the Poly Performance kit as well as the local Ace bins to see if they have anything large enough.

My concern, with the stock bolts, is their ability to take my cranking to 130-ft/lbs. When I did the rears, I kept thinking, "It's gonna snap...I know it's gonna snap...". This happened on my TJ track bar bolt.
Look at Poly's kit description. It has all the specs for the bolts they use. Poly seems to get most of their hardware from Fastenal and it's always top quality. I just didn't want to wait for shipping so I cleaned out the local bins. Poly would have been less expensive, pretty sure.

The factory bolts are pretty stout. LCA torque is 120 ft lbs, they can take it easily. Problems are simply that they're metric bolts in standard holes, and they're not shouldered.
 

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Discussion Starter · #11 ·

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It's probably cheaper than buying them individually. Plus, you know you'll get good stuff.
 
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