Pontiac G8 Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
680 Posts
Discussion Starter #1
Well, 11 years on old, stock bushings is enough. Time to replace and upgrade. I've already done SuperPro engine mounts, about to replace the trans mount with a new OE one, and just replaced my carrier bearing a couple weeks ago. Moving down the line, time to tackle all of the rear subframe.

Looking for confirmation on my parts list, and/or anything I should change or additional parts I should consider.
  • 3.27 diff (already have)
  • SuperPro diff bushings (SPF-KIT176K)
  • SuperPro cradle inserts (SPF-KIT176K)
  • BMR toe rods (TR002)
  • BMR trailing arms (TCA026)
  • BMR trailing arm outer bushings (BK006)
  • Z/28 rear lower control arms (GM - 23484878)
  • Z/28 upper, inner control arm bushings (GM - 23104906 & 23104907)
I want to replace pretty much all of the hardware/bolts/nuts. Anyone have part numbers handy? I've found some, but also looking to confirm.

Lastly, cradle inserts... are the stock cradle bushings worth replacing, or just leave them? I'm not sure what to expect.

Thanks!
 

·
Premium Member
Joined
·
1,369 Posts
Well, 11 years on old, stock bushings is enough. Time to replace and upgrade. I've already done SuperPro engine mounts, about to replace the trans mount with a new OE one, and just replaced my carrier bearing a couple weeks ago. Moving down the line, time to tackle all of the rear subframe.

Looking for confirmation on my parts list, and/or anything I should change or additional parts I should consider.
  • 3.27 diff (already have)
  • SuperPro diff bushings (SPF-KIT176K)
  • SuperPro cradle inserts (SPF-KIT176K)
  • BMR toe rods (TR002)
  • BMR trailing arms (TCA026)
  • BMR trailing arm outer bushings (BK006)
  • Z/28 rear lower control arms (GM - 23484878)
  • Z/28 upper, inner control arm bushings (GM - 23104906 & 23104907)
I want to replace pretty much all of the hardware/bolts/nuts. Anyone have part numbers handy? I've found some, but also looking to confirm.

Lastly, cradle inserts... are the stock cradle bushings worth replacing, or just leave them? I'm not sure what to expect.

Thanks!
The Z/28 rear lower control arms will raise your vehicle. Apparently, the hole where the shock attaches to the control arm is higher than on the Zeta sedans, thus raising the vehicle.

holeproblem.jpg


I would also look into upgrading the rear sway bar to the 2015-2017 SS version. It's a refinement to the Zeta chassis that's accessible. The rear lower control arms for said vehicle would be required but since they're "universal," you can hold off on the sway bar upgrade.
 

·
Registered
Joined
·
680 Posts
Discussion Starter #3
The Z/28 rear lower control arms will raise your vehicle. Apparently, the hole where the shock attaches to the control arm is higher than on the Zeta sedans, thus raising the vehicle.

I would also look into upgrading the rear sway bar to the 2015-2017 SS version. It's a refinement to the Zeta chassis that's accessible. The rear lower control arms for said vehicle would be required but since they're "universal," you can hold off on the sway bar upgrade.
Oh, thanks for the info on the Z/28 control arms.

I'll investigate the sway bar, and if I understand correctly, I then need the 2015-2017 lower control arms. Will they raise the car as well, or are they same as stock?
 

·
Premium Member
Joined
·
1,369 Posts
Oh, thanks for the info on the Z/28 control arms.

I'll investigate the sway bar, and if I understand correctly, I then need the 2015-2017 lower control arms. Will they raise the car as well, or are they same as stock?
Apparently it keeps the stock ride height.

You can keep your existing sway bar with the 2015-2017 SS rear lower control arms.
 

·
Registered
Joined
·
680 Posts
Discussion Starter #5
Apparently it keeps the stock ride height.

You can keep your existing sway bar with the 2015-2017 SS rear lower control arms.
Awesome. But looking at it further, I'm going to go with stock rear LCAs. Mevotech ones are $55 per side, and rival Moog for quality. Also going to go with SuperPro outer LCA bushings, as the current ones are probably pretty shot.

Lastly, I called Pace Performance, and here is the list of hardware with part numbers:
  • Bolts
    • 92138973 - Subframe connectors - x4
    • 92139105 - Toe Rod to Knuckle - x2
    • 92139134 - Toe Rod to Subframe - x2
    • 11589279 - Trailing Arm to Knuckle - x2
    • 92138876 - Trailing Arm to Subframe - x2
    • 11589279 - Lower Control Arm to Knuckle - x2
    • 92139133 - Lower Control Arm to Subframe - x2
    • 92139090 - Upper Control Arm - x2
    • 11589279 - Upper Control Arm Outer - x2
  • Nuts
    • 11900443 - x12 - These are the same everywhere minus the UCA-Outer
    • 11516078 - x2 - UCA-Outer
Pricing it out comes to over $250. :oops:

I'm definitely ordering new subframe connector bolts, and I guess we'll see how many of the others break or have to be cut.
 

·
Registered
Joined
·
2,837 Posts
92138876 - Trailing Arm to Subframe - x2

I know these have thread locker on them. New ones would be a good idea.

When you take the bolts out of the trailing arm-knuckle joint, look at the washers on the bolts (11589279 - Trailing Arm to Knuckle - x2). My stock ones had offsets to hold the bolt in the center of the slotted trailing arm. The new arms I put in did not have slots, so the washers with offsets would not make a good bolted joint. They are close to the same size as the flange on the bolt and nut, so I ditched the washers.
 

·
Registered
Joined
·
680 Posts
Discussion Starter #7
92138876 - Trailing Arm to Subframe - x2

I know these have thread locker on them. New ones would be a good idea.

When you take the bolts out of the trailing arm-knuckle joint, look at the washers on the bolts (11589279 - Trailing Arm to Knuckle - x2). My stock ones had offsets to hold the bolt in the center of the slotted trailing arm. The new arms I put in did not have slots, so the washers with offsets would not make a good bolted joint. They are close to the same size as the flange on the bolt and nut, so I ditched the washers.
Good point.

I'll watch out for that. Did you do the BMR trailing arms?
 

·
Registered
Joined
·
2,837 Posts
Spohn trailing arms.
 

·
Premium Member
Joined
·
1,369 Posts
Awesome. But looking at it further, I'm going to go with stock rear LCAs. Mevotech ones are $55 per side, and rival Moog for quality.
Yes, but if you ever wanted to upgrade your rear sway bar to the 2015-2017 SS style (also the same style on the later 5th generation Camaros (2013+ IIRC), 6th generation Camaros have the bar connected to the knuckle, which is even further out), you'd have to change out the rear lower control arms again.

Not to mention the fact that the 2015-2017 SS rear lower control arms have different part numbers depending on the side of the vehicle it's used on. This is because the inner bushing, while identical in both arms, is mounted differently depending on which side the arm is on the vehicle.

Also, I'm unaware if Mevotech has reinforced the control arms where the end link attaches.

Also going to go with SuperPro outer LCA bushings, as the current ones are probably pretty shot.
That or the OEM sealed ball joint as used in the GXP.
 
1 - 9 of 9 Posts
Top