Sorry if this has been answered- torque specs RR LCA

[el ess A]

Looking for torque specs for rear LCAs. (lower shock bolt and both end bolts)

Doing the swap over for the ZL1/1LE bar in the back so that means updating the LCAs on the back of the 2010 to the 2012-up style.

With that, does anyone know off hand what torque specs are for the bolts, if any?

No biggie if you don't, but thought I'd ask. TIA.

[ackeight]

FRONT
Lower control arm bushings 37ft/lbs. Then 150 degrees.
Lower control arm ball joint 18ft/lbs. Then 120 degrees.
REAR
Lower control arm inner bushing at adjuster 85ft/lbs.
Lower control arm at knuckle assembly 30ft/lbs. Then 120 degrees

[el ess A]

Thanks.

So I'm guessing when you say "then xx degrees" that means it's one of those use once and replace it bolts? Torque to yield?

[ackeight]

I reused the knuckle to lca bolt. I don't think it will be an issue. Haven't heard of people getting new ones when doing suspension work.

[el ess A]

My first time (breaking my cherry) getting underneath the differential of the car. Figure I'll replace the fluid when I do the sway bar swap as well.

Thanks for the help.

[toml_pa]

Originally Posted by el ess A

Thanks.

So I'm guessing when you say "then xx degrees" that means it's one of those use once and replace it bolts? Torque to yield?

These are the torque specs I used along with blue Loctite and didn't bother with the angle stuff. Had my rear sub-frame out and completely stripped for all new bushings two Winters ago with no problems since. The general consensus seems to be you can use bolts several times before replacing as long as you use blue Loctite.

REAR

Cradle to body - 130 ft/lbs
Differential bushings to sub-frame - 60 ft/lbs
Calipers to knuckle - 65 ft/lbs
Upper strut to body - 43 ft/lbs
Lower strut to lower control arm - 60 ft/lbs

Sway bar bracket to sub-frame (M8) (2010-11) - 22 ft/lbs
Sway bar bracket to sub-frame (M10) (2012+) - 43 ft/lbs
Sway bar to lower control arm (OLD) (2010-11) - 36 ft/lbs
Sway bar to lower control arm (NEW) (2012+) - 19 ft/lbs-228 in/lbs

Upper control arm saddle bolts (4) to sub-frame - 85 ft/lbs
Upper control arm rear bolt to bushing - 130 ft/lbs
Upper control arm front inner pivot mount - 130 ft/lbs
Upper control arm to knuckle - 85 ft/lbs
Lower control arm to sub-frame - 85 ft/lbs
Lower control arm to knuckle - 85 ft/lbs
Trailing arm to sub-frame - 80 ft/lbs
Trailing arm to knuckle - 80 ft/lbs
Toe rod to sub-frame - 85 ft/lbs
Toe rod to knuckle - 103 ft/lbs
Wheel bearing to knuckle - 85 ft/lbs

FRONT

Calipers to knuckle - 104 ft/lbs
Lower control arm inner - 85 ft/lbs
Lower control arm outer - 85 ft/lbs
Radius rod inner - 85 ft/lbs
Radius rod outer - 85 ft/lbs
Wheel bearing to knuckle - 79 ft/lbs
Strut top nut - 52 ft/lbs
Strut retaining nut (inside) - 52 ft/lbs
Strut to knuckle - 161 ft/lbs

Sway bar bracket to sub-frame (M8) (2010-11) - 22 ft/lbs-264 in/lbs
Sway bar bracket to subfamily (M10) (2012+) - 43 ft/lbs
Sway bar end links both ends (M10) (2010-11) - 36 ft/lbs
Sway bar end links at sway bar (M12) (2012+) - 36 ft/lbs
Sway bar end links at strut (M12) (2012+) - 52 ft/lbs

Tie rod to knuckle - 55 ft/lbs
Tie rod inner nut - 55 ft/lbs

[ackeight]

Originally Posted by el ess A

My first time (breaking my cherry) getting underneath the differential of the car. Figure I'll replace the fluid when I do the sway bar swap as well.

Thanks for the help.

It looks daunting the 1st time but is easy. Do you have eccentric bolts with more adjustability than stock? Lowered?
As far as the diff what fluid will you use? I used mobil1 75w90 and a little bit of friction modifier.

[el ess A]

Originally Posted by ackeight

It looks daunting the 1st time but is easy. Do you have eccentric bolts with more adjustability than stock? Lowered?
As far as the diff what fluid will you use? I used mobil1 75w90 and a little bit of friction modifier.

No, it's still all stock suspension underneath. I have the stock bolts and really was hoping just to reuse those but will buy new ones if required.

I saw a while back where Pedders had some thicker eccentric bolts with more camber adjust, but I'm not going that route. I just want to stiffen up the sway bars and reduce the understeer a little on the street. That's why I'm sticking to GM parts for the upgrade. Going to start with the ZL1 front/rear bar setup with the stock tires/wheels. If I go square by putting on my spare set of rear wheels/tires on the front, I'll put the 1LE bar up there.

I do have a slight concern though that if I do replace the LCA, that the car would require a re-alignment. Or if I match mark the eccentric locations before removal, would that suffice? Again, no experience with these IRS setups.

I MIGHT go ahead and install this MBRP ProSeries 304 stainless catback I've got laying around as well (still new in the box). Depends on how the LCA replacement goes. I'm not immune at all to working on cars, I've just never got into an IRS setup before. Looks pretty straightforward.

As far as the lube, I understand the GM #88900401 is GL-5 rated as well as the Mobil 1 LS 75W-90. Mobil 1 is 11 bucks at Advance Auto and GM list price on their grape oil is over $27 list, $20.65 my cost locally. The additive is relatively cheap, I can get that for $9.75 per bottle at the dealer. So I can spend $21 or $30 depending on who's oil I use. Probably just go with the grape GM stuff because that way GM can't complain about the "wrong" oil if there's an issue with the differential, and I got to swing by the GM dealer for the limited slip additive anyway.

[el ess A]

Originally Posted by toml_pa

These are the torque specs I used along with blue Loctite and didn't bother with the angle stuff. ....

Great info!! Thanks a ton!

[Fast6.3]

I used redline without friction modifier and so far so good no noise or problems