[Alpha1BC]

Did some digging on a few open items on the main post this morning. Sorry if I'm addressing stuff that's already been covered between the first post and my post.

Originally Posted by Ryephile

Front Links for Stabilizer bars. FEA not confirmed yet.
FE2 = 20761141 & 20761142
FE3, FE4 = 23240970 & 23240971

Looking at the GM parts catalog, FEA is listed to have the same stab bar links as the FE3, FE4 options, PNs 23240970/71.

Originally Posted by Ryephile

Front strut mounts. This is a little strange. All cars get # 840103429, except F55 [aka MRC] FE3 cars, those get 84013428.

I'm sure this is already known, but the DSSV suspension gets it's own special top mount that is included with the damper (I don't have an individual part number atm). Aside from that, you hit the nail on the head that all the passive suspension cars get 840103429 and all the MRC cars get 84013428. Reason for that is the tuning is mainly handled by the damper valving so only one top mount is needed MRC and one for non-MRC.

Originally Posted by Ryephile

Front DSSV housings for FEA, not sure what the two sets of numbers is about:
AF9R,AF9P = 84384331 & 84384332
AFWY,AFWX = 84331745 & 84331746
DSSV strut inserts, the dampers themselves = 84331747 for both left and right

This one is interesting. Through google I see what's listed here for the specific PNs being housings only, but through the catalog I see those PNs listed as the entire DSSV strut assembly (top mount/damper, isolators, spring, dust boot, and housing all bolted together). Not sure which I believe more at this point, but I will say I find it odd that the google search sources show it as being the outer housing and spring isolators. Seems like a weird combo to me... I'm also trying to look into why there are 2 different sets of PNs for those. I have an idea of what it could be, but I want to confirm first haha.

[Ryephile]

Thanks, I'll update the first two items.

[WyGuy]

Originally Posted by Ryephile

There are a couple single part number surprises.
Rear Links for Stabilizer Bar. Only one part number here, it's # 23105170
Rear Lower Control Arms for all were 23282356 & 23282357, superseded by 84382226 & 84382227.

Any idea what the reasoning is for the new part numbers for the rear control arms? I had to replace the right rear and ended up with the older number, just curious if there are any physical differences between the two.

[Ryephile]

Originally Posted by WyGuy

Any idea what the reasoning is for the new part numbers for the rear control arms? I had to replace the right rear and ended up with the older number, just curious if there are any physical differences between the two.

It's tough to say for sure, or make a blanket statement. I know one way is it can be a new supplier, or even a revised supplier assembly process can force a new part number as a way to do revision control. What's also possible is there could be a design update, but it wouldn't be safety-critical as that should trigger a TSB.

I wouldn't stress about it. For example, I had the old and new part number FE4/FEA rear knuckles side-by-side and other than the casting numbers I was unable to discern a useful difference.

[Mrfixxit7]

I just recently upgraded my FE3 to FE4 suspension. Here is my list of part numbers to include the TTY bolts and all the torque specs. I went with ZL1 springs due to having a supercharger.

Front suspension:
-Sway bar – Part # 84052981
(Clamp nuts 16 ft lbs)

-Links for sway bar SAME (FE3 and FE4) - part # 23240970 & 23240971
(Nuts 74 ft lbs)

-"Ride" Links. These are the diagonal front-front control arms – part # 84051641 & 84051642
(bolts 74 ft lbs/90-105 degrees TTY) Part # 11610915 (2) bolts

-"Handling" Links. These are the lateral front-rear control arms - part # 23317367 & 23317368
(bolts 74 ft lbs/90-105 degrees TTY) Part # 11611268 (2) bolts

-Strut mounts - Part # 84013428 (for MRC)
(Nuts 37 ft lbs)

-Springs – Part # 84312735 (ZL1)

-Struts (MRC) - Part # 84115887 & 84115888

Rear suspension:
-Sway bar – Part # 84026864
(Insulator clamp bolts 43 ft lbs TTY)
Part # 11548327 (1) stud; 11588723 (3) bolts

- Links for sway bars SAME (FE3 and FE4) – Part # 23105170
(Bolts 43 ft lbs TTY; nuts 32 ft lbs) Part # 11518630 (2) bolts

- Adjust Links, (aka the toe link) SAME (FE3 and FE4) – Part # 23117751
(Bolts (inner) for alignment; bolts (outer) 74 ft lbs/105 degrees TTY) Part # 11609598 outer same (2) bolts

- Lower Control arms SAME (FE3 and FE4) - Part # 23282356 & 23282357
(Bolts (inner) for alignment; bolts (outer) 110 ft lbs/105 degrees TTY) Part # 11609598 outer (2) bolts

- *Trailing arm/links (upper) – Part # 84059622 (had same stamped P/Ns as FE3 but sticker was added to make it FE4)
(Bolts (inner) 52 ft lbs/105 degrees TTY; bolts (outer) 74 ft lbs/105 degrees TTY) Part # 11610908 inner & outer same (4) bolts

- *Trailing arm/links (lower) – Part # 84048678 (had same stamped P/Ns as FE3 but sticker was added to make it FE4)
(Nuts (inner) 52 ft lbs/105 degrees; bolts (outer) 74 ft lbs/105 degrees TTY)
Part # 11610908 outer (2) bolts

- Upper control arm or Lateral link SAME (FE3 and FE4)- Part # 22974128
(Bolts (inner) 52 ft lbs/105 degrees TTY; bolts (outer) 52 ft lbs/105 degrees TTY) Part # 11610908 inner & outer same (4) bolts

-Knuckles - Part # 84089877 & 84089878

-Springs - Part # 84079567 (ZL1)

-MRC dampers (rear)- Part # 23281657 & 84219921
(Bolts 52 ft lbs/105 degrees TTY) Part # 11609598 lower bolts (2) bolts

Thanks for all the great info on this thread!

[Scoooter12]

[F1FTY]

Thank you for this thread!

I put the GM 1LE (FE4) Suspension Kit Upgrade on my FE3 MRC SS with 1LE (FE4) upper and lower rear trailing arms last year and in reading through this thread, to convert the rest of my FE3 parts over to FE4 parts I would only need to buy:

Front "Ride" Links. These are the diagonal front-front control arms – part # 84051641 & 84051642 ($204 total)

and

Rear Knuckles
FE4 & FEA = 84258571 & 84258572 ($202 total)

and

Rear Cradle
FE4 = 84053249 ($456 total)

Am I missing anything else? I don't want to go full FEA since it's setup for the DSSV/sways.

Thanks!

[Ryephile]

That sounds correct. That said, the rear cradle is a non-trivial swap. Consider the BMR BK063 rear cradle bushing inserts instead, as they're designed for the FE3 cradle bushings and are DIY with shadetree mechanic tools. If cost & labor is no-object, by all means go for the whole rear cradle.

[F1FTY]

Originally Posted by Ryephile

That sounds correct. That said, the rear cradle is a non-trivial swap. Consider the BMR BK063 rear cradle bushing inserts instead, as they're designed for the FE3 cradle bushings and are DIY with shadetree mechanic tools. If cost & labor is no-object, by all means go for the whole rear cradle.

Excellent, thank you for the quick response and of course for putting this monster thread together! To compare costs for future readers of this thread, at this time the cost difference is:

Whole new FE4 cradle is $456 (rounded up) from ThatGMPartsGuy

BMR rear cradle lockout kit (BK063) is $360 (rounded up list price).

If the bushings in the cradle are the only difference, swapping to the FE4 cradle does not make sense for a non-1LE/ZL1 owner.

[Mrfixxit7]

Fifty,
When I swapped out the rear knuckles I didn’t notice any physical difference between the two, maybe the bushing compound is different. They were a pain to swap out because you have to remove the rear brakes/e-brake setup and rear hub.

[F1FTY]

Originally Posted by Mrfixxit7

Fifty,
When I swapped out the rear knuckles I didn’t notice any physical difference between the two, maybe the bushing compound is different. They were a pain to swap out because you have to remove the rear brakes/e-brake setup and rear hub.

Sounds like a lot of the FE3 to FE4 links and cradle are just the bushings then. If only we could just buy the bushings and they didn’t require a press to swap in.

I may just get the front links and rear cradle bushings and call it a day.

[D K]

So what would it take to turn

A) FE3 into FE4?
B) FE3 into FEA?
C) FE4 into FEA?

Trying to understand the differences in suspension between the SS and SS 1LE as well as the SS 1LE and the ZL1 LE

Ideally my combination would be an SS with the ZL1 1LE suspension package but it might be cost prohibitive.
This would also clarify whether I should hunt down a SS 1LE or take the cost savings and start with a base SS

Thank you.

[TRZ06]

Originally Posted by D K

So what would it take to turn

A) FE3 into FE4?
B) FE3 into FEA?
C) FE4 into FEA?

Trying to understand the differences in suspension between the SS and SS 1LE as well as the SS 1LE and the ZL1 LE

Ideally my combination would be an SS with the ZL1 1LE suspension package but it might be cost prohibitive.
This would also clarify whether I should hunt down a SS 1LE or take the cost savings and start with a base SS

Thank you.

Depends on your goals. I almost got the ZL1 1LE, but realized for a daily driver that will rarely see the track, it was overkill ride quality wise, gas mileage wise, and tire wise.

The perfect combo for me for a daily driver with maybe a few track days a year is the SS 1LE, and upgrade the rear cradle bushings to the solid ZL1 1LE bushings. It gives you the rear-end stability of the ZL1 1LE, but with the benefit of having MRC.

There is one member here who upgraded his ZL1 (same suspension set-up as the SS 1LE) to the DSSV ZL1 1LE suspension and was not impressed with the ride quality and his lap times did not improve.

[D K]

Originally Posted by TRZ06

Depends on your goals. I almost got the ZL1 1LE, but realized for a daily driver that will rarely see the track, it was overkill ride quality wise, gas mileage wise, and tire wise.

The perfect combo for me for a daily driver with maybe a few track days a year is the SS 1LE, and upgrade the rear cradle bushings to the solid ZL1 1LE bushings. It gives you the rear-end stability of the ZL1 1LE, but with the benefit of having MRC.

There is one member here who upgraded his ZL1 (same suspension set-up as the SS 1LE) to the DSSV ZL1 1LE suspension and was not impressed with the ride quality and his lap times did not improve.

Thanks

My car would certainly see many track days a year and I would not be concerned with the ride quality at all.

Im just trying to see what the exact differences are, mostly between the FEA and the FE4. does the FEA come with DSSV?