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Let's say I mix and match super pro and whiteline... which bushings will contribute the most to a harsh ride on 19" wheels? I'm getting the front strut mounts SPF1590AK already, but would sway bar bushings in whiteline poly contribute to a lot of harshness? I may need to get the car on the lift and get a deeper inspection on bushings so I don't order too many. Do you think we can identify all worn bushings or do some of them need to be identified after components are pulled off the car?
You can mix and match as I did. I used Whiteline end links and sway bar bushings as I did not see that SuperPro offered them.

Sway bar bushings will not add any harshness.

Some parts can be identified as bad on the car (strut mounts, end links, ball joints, etc.). Others require some or full disassembly. I didn't know that my sway bar and radius rod bushings were fine until I pulled them off and closely inspected them. But I had already purchased the new parts so I installed them. In most cases, the aftermarket parts are an upgrade even if the stockers are good - the only exception perhaps being the sway bar bushings.
 

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Bear in mind harshness, stiffness, firmness are both relative and subjective according to personal taste. The W53152 part correct number seems to be correct and cannot say which is a better product.
 
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Discussion Starter · #23 ·
You can mix and match as I did. I used Whiteline end links and sway bar bushings as I did not see that SuperPro offered them.

Sway bar bushings will not add any harshness.

Some parts can be identified as bad on the car (strut mounts, end links, ball joints, etc.). Others require some or full disassembly. I didn't know that my sway bar and radius rod bushings were fine until I pulled them off and closely inspected them. But I had already purchased the new parts so I installed them. In most cases, the aftermarket parts are an upgrade even if the stockers are good - the only exception perhaps being the sway bar bushings.
Thanks for the feedback on that. The mechanic recommended the sway bar bushings be replaced and Whiteline has them for a reasonable price. What about changing out rear control arm bushings with some Whiteline? Any idea which bushings I should do Super Pro elastomer vs Whiteline poly in that area?
 

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As for sway bar bushings, both the Whiteline and Nolathane have the greaseless PTFE lining for smooth squeak free movement. The bar not sticking to the bushing is important to smooth ride quality. Sway bar bushings have a small effect on harshness. They make turn response faster and reduce lean. You have the front strut mount right. I like the Moog sway bar links. The tubing is stiffer than the usual thinner metal rod that connects them. Better to transfer more load to the bar. For front control arms get rid of the stock ones.
The radius rod bushing is so soft because it is liquid (dexcool) filled. I know the Mevotech has a solid rubber bushing to maintain suspension geometry and steering feel. The greaseable all metal ball joint helps too.
In the rear it is cheaper and better to use the Dorman 524-564 toe rods with spherical joints instead of bushings. This will reduce hop and deflection accelerating and braking. The biggest flex joint is the big rear upper control arm bushing. It is soft, voided rubber. It is also a big cause of wheel hop. The Z-28 version is solid and compressed rubber to limit flex but not be hard as a rock like the BMR delrin ones. It’s a real race. quality part and will add some harshness. Have you done the poly subframe inserts yet?
 

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Hello all,

Still have the 2009 G8 GT (not a 2009.5) at 89k miles and it needs suspension work. I'm not really a gearhead and pay mechanics to do my work for me, but I still like the car and want to keep it going and I have never done an extensive suspension job other than replace one bad component at a time. I had the ABS light issue the mechanic solved that issue by replacing a wheel sensor in the rear driver side wheel (that was fun to troubleshoot and diagnose). He showed me on the lift that the rear shock was blown and that a number of black rubber bushings, specially in the rear are basically falling apart. His recommendation was to replace the following components last time I spoke with him:

-front stabilizer bar bushings
-both rear sway bar links
-Two rear struts
-rear control arm bushings
-rear stabilizer bar bushings (optional)

As for symptom's car leans on driver side due to the blown shock and when it gets cold (40F or lower), it makes a rattling sound while driving. It goes away when it warms up. This has been going on for years and that was why I replaced a sway bar link but it didn't go away and I just put up with it. It also just doesn't feel like it did when I first bought it.

I started looking around on BMR, Whiteline's site and reading a lot of posts here and I started to think I should probably go ahead and replace more suspension components so I don't have to keep coming back for suspension work. The only suspension components that have ever been replaced are a sway bar link 5 years ago in the front and one strut from running a curb back when I first got the car (I'm original and only owner). Since I'm doing the rear shocks, the fronts may not be far behind and he is going to have the car up on the lift to replace bushings and rear shocks, so why not get more bushings and do the other shocks? This car is not for sport, more for highway driving to work on occasion since I work from home a lot. Up until the last year, the car was sitting in the sun for most of its life and the Texas heat probably didn't help the components under the carriage. Now, it spends most of its time in the garage after moving to a bigger house (and it's not the main family car which is an SUV). More research led to more parts getting added to my list, but I'm trying to figure out if I have a good list here or if I'm going overboard.

This is what I have come up with to add to the list along with part numbers and prices:

Struts:
1x - MONROE 553016 ($94.79)
1x - MONROE 553017 ($94.79)
2x - MONROE 553018 ($68.79)

OR Ac/Delco parts:
1x - ACDELCO 506882 - $99.79
1x - ACDELCO 506883 - $99.79
2x - ACDELCO 560726 - $84.79



Strut mounts:
1x - SuperPro AK SPF1590AK strut mount ($160)

Rear sway bar links:
2x - ACDELCO 45G20736 ($17.76) or 2x MOOG K750184 ($39.89)

Front sway bar links:
1x - MOOG K750162 ($19.25)
1x - MOOG K750163 ($19.56)

Whiteline poly bushings:
1x - Whiteline Rear Control arm - lower rear outer bushing (W63430) - $91.38
1x - Whiteline Rear Control arm - lower rear inner bushing (W63154A) - $54.74
1x - Whiteline Rear Control arm - upper front inner bushing (W63157) - $45.56
1x - Whiteline Rear Control arm - lower front outer bushing (W63155) - $54.74
1x - Whiteline Front Sway bar - mount bushing (W23153G) - $20.91
1x - Whiteline Rear Sway bar - mount bushing (W21484G) - $18.19
1x - Whiteline Rear Shock absorber - lower bushing (W33168) - $36.38

Whiteline has a sale going with 15% w/ free shipping and no sales tax and Rock Auto has a number of parts in stock. The only part that is not from these two sites is the SPF1590K which MA Performance has right now via ebay/amazon.

I was looking at Whiteline's Front Control Lower bushing and Front Radium arm Lower bushing but then I started doing research on the LCAs themselves. It sounds like a lot of people here have already replace theirs multiple times due to that ball joint, which cannot be replaced separately. In fact, I read the TSB about the winter rattling noise and probably should have had GM replace mine, but those are original. Is it possible the sound is my LCA arm on the driver side? I didn't talk to the mechanic about this yet but I don't think he really looked at that yet.

Rock Auto offers Mevotech, Moog and AC Delco. I saw a lot of Mevotech recommendations. Would the appopriate 4 front control arm parts be these?:
  • MEVOTECH CMS501097 (radius arm) - $73
  • MEVOTECH CMS501096 (radius arm) - $73
  • MEVOTECH CMS501098 (control arm) - $62
  • MEVOTECH CMS501099 (control arm) - $64

I am not looking to break the bank on control arms and mainly just want the suspension to be tight and last me for years of highway and light city driving. Also, I opted to just keep the stock springs as there is nothing wrong with the ones I have. I'm not trying to lower the car to the ground.

The questions I have here are:
1) Am I missing anything or should I remove anything?
2) Should I go with the AC/Delco version of these PPV struts or the Monroes? What is the difference? It appears the AC/Delco upgraded their warranty to lifetime while the Monroe's is now only 3 years. I think it used to be the opposite? AC/Delco rear struts are significantly more in cost.
3) With the struts, will the car ride higher, lower or the same? Any drawbacks to the new height?
4) How stiff of a ride will this be with stock springs and PPV the bushings I selected? Seems like those front strut mounts and the PPVs pair up nice. I don't mind it a little stiffer vs what I got right now, which is a floaty, squeaky mess.
5) Is the rear shock absorber bushing necessary for a Monroe 553018 (or AC/Delco) or does it have a good one already?
6) Should I get front control arm bushings or just get new control arms?
7) Which rear sway bar links are good for a light to medium cruiser? Big price difference between AC Delco and Moog.
8) Should I go ahead and replace the front sway bar links? He said they looked okay but it seems cheap to just go ahead and do them since they need to come off anyway and it seems like a cheap part.
9) Should I have him do an alignment or do I need to go somewhere special for that? I haven't asked him if he can do this, but he is very reasonable on all his services w/ full shop + garage/lift and seems pretty capable so far.

Anyway, I want to pull the trigger on these parts and get everything right the first time. I am trying to avoid having to buy anything major locally, but also don't want to buy things I don't need since I'll have to ship it back at my expense. We have autozone, advanced auto parts, o'reilly's etc. nearby for things we need to get it done if need be. He also mentioned I could swap out my brake pads if they are worn (brake job done 7 years ago w/ posi quiet pads and centric rotors). July 4th deals still going on for now but that will end soon.

Sorry for the long post, hope the experts on G8 suspensions can help me out!
Hey I went with the BMR replacements
 

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Can't delete double post...ugh.
 

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Discussion Starter · #29 ·
As for sway bar bushings, both the Whiteline and Nolathane have the greaseless PTFE lining for smooth squeak free movement. The bar not sticking to the bushing is important to smooth ride quality. Sway bar bushings have a small effect on harshness. They make turn response faster and reduce lean. You have the front strut mount right. I like the Moog sway bar links. The tubing is stiffer than the usual thinner metal rod that connects them. Better to transfer more load to the bar. For front control arms get rid of the stock ones.
The radius rod bushing is so soft because it is liquid (dexcool) filled. I know the Mevotech has a solid rubber bushing to maintain suspension geometry and steering feel. The greaseable all metal ball joint helps too.
In the rear it is cheaper and better to use the Dorman 524-564 toe rods with spherical joints instead of bushings. This will reduce hop and deflection accelerating and braking. The biggest flex joint is the big rear upper control arm bushing. It is soft, voided rubber. It is also a big cause of wheel hop. The Z-28 version is solid and compressed rubber to limit flex but not be hard as a rock like the BMR delrin ones. It’s a real race. quality part and will add some harshness. Have you done the poly subframe inserts yet?
That is incredibly detailed information and I'm going to investigate these parts. I had not looked at toe rods yet.

I haven't done any suspension work other than what I posted originally on a strut and sway bar link replacement years ago. I was going to take it back the mechanic to really investigate the bushings in more detail. I still have a discounted whiteline invoice with the 15% discounts with these parts in it:

Product image Description Quantity Price
Rear Control arm - lower rear outer bushing
1
Rear Control arm - lower rear outer bushing 1 $107.50
Rear Control arm - upper front inner bushing
1
Rear Control arm - upper front inner bushing 1 $53.60
Rear Sway bar - mount bushing
1
Rear Sway bar - mount bushing 1 $21.40
Rear Control arm - lower front outer bushing
1
Rear Control arm - lower front outer bushing 1 $64.40
Rear Control arm - lower rear inner bushing
1
Rear Control arm - lower rear inner bushing 1 $64.40
Front Sway bar - mount bushing
1
Front Sway bar - mount bushing 1 $24.60
Front Steering - rack and pinion mount bushing
1
Front Steering - rack and pinion mount bushing 1 $32.00
Total is $336.94 for whiteline bushings from this list and the other parts would be ordered from rock auto (struts, sway bar links, etc.) I haven't pulled the trigger on it just yet because I really want the mechanic to do a more thorough investigation of the bushings before I order all this stuff and I have been swamped at work lately. I read some of the literature on poly vs rubber vs race car bearings and poly seems to fall in the middle and requires greasing or it could squeak. The whiteline/superpro guy (same company) indicate that the durometer of the whiteline bushings is about 85 durometer while rubber is in the 60s or so. He was not able to find the durometer on the SPF1590AK on his system. You find out about durometer at Durometer and Suspension Bushings | Suspension.com . They sent me a lot of literature on bushings. I just don't know how poly feels because I've only ever run in cars on rubber.

Does anyone know how much softer the super pro bushings really are in terms of durometer?
 

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So I just got done with full suspension overhaul (front overhaul and zeta II rear swap) and poly-ed the whole car.

My thoughts (daily driver point of view):

if i was doing it again for the front:
Pedder strut mounts, or something close to stock (this where road NVH comes thru)
Superpro linkage caster and control arms
whiteline end links
any strut to your preference
Also since you are "in there" I also did CTS-V 4 pot brake upgrade with G8 Russel lines (huge difference, awesome pedal feel)

If i was doing it again for the rear:
BMR toe rods and trailing arms
Shock and springs..your taste
Stock replacement lower control arms

and that's it

If you poly the diff, you may start to hear gear whine
if you poly the cradle you will hear more road NVH.
 

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I installed the Monroe PPV Severe service struts with OEM strut mounts, mevotech front control arms and sway bar links. I'm personally happy with the ride. It is stiffer compared to the stock struts but it corners much better and feels a bit more planted to me. I do a good bit of highway driving so I would rather not feel every imperfection in the road while still having an increased handling performance.
 

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I installed the Monroe PPV Severe service struts with OEM strut mounts, mevotech front control arms and sway bar links. I'm personally happy with the ride. It is stiffer compared to the stock struts but it corners much better and feels a bit more planted to me. I do a good bit of highway driving so I would rather not feel every imperfection in the road while still having an increased handling performance.
Better keep an eye on those OEM strut mounts. I watched mine collapse within 8k miles (~2011) from leaving the factory. Replaced with poly but all my other bushings are still factory so no noticeable impact on NVH.

I also went with PPV dampers back in 2015 as the factory Fe2s sucked from the get-go (highway float a year after leaving the dealer? Really!). Stuck with the crap Fe2s until I replaced the crap GY LS tires in 2015 with Michelin Pilot Sport AS3s. The PPVs really have the G8 glued down and smooth enough as my G8 is now my touring/road trip car. (note: everything else in the suspension is stock with 18" wheels and just replaced the AS3s with grand touring tires)
 

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i felt no increase in NVH with the SuperPro polyelast strut mounts, LCA's, and radius arms. And I'm pretty sensitive to it.
 

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i felt no increase in NVH with the SuperPro polyelast strut mounts, LCA's, and radius arms. And I'm pretty sensitive to it.
Yeah, heard they are the type to go with as they don't increase NVH like regular poly. But they weren't available 10 yrs ago. On that note, my poly bushings, after settling in, haven't budged.
 
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