High mileage suspension refresh. Best options for OEM+ setup?

[CTB727]

I'm in the process of refreshing the suspension on my 125k mile 2013 BRZ. Currently the car is stock as it's my DD, but for about 3 years I had it prepped for STX back when I autocrossed it regularly, so it has definitely seen some wear from hard driving.



I've read through Racecomp Engineering's thread to get started but I have some questions.


My car is showing various symptoms of what I can only assume to be worn bushings and components. There is a pull to the left under acceleration at highway speeds, then a pull to the right under deceleration. Steering feel isn't what it used to be, the car feels like it wanders within the lane and I'm constantly having to make steering inputs to keep it centered, etc. Basically feels like a driving on a windy day, but all the time. All wheel bearings have been replaced as well as brake pads, and the rotors and calipers looked fine.



Goal: Get the car to feel like new again, but with an OEM+ setup. I'm fine with a slight increase in NVH as long as it doesn't become race car loud.



So my question is, which parts should I stick with OEM and which are best to go aftermarket? Below is my plan so far, and let me know if there's something I should switch out.



Front suspension:

• OEM front LCAs (in order to to have new ball joints and bushings)
• OEM sway bar bushings
• OEM sway bar end links (driver's side looked rough, possibly causing front end clunk)
• Tie rods - how do I know they're bad? Are they worth replacing as preventive measure?
• Found some low mileage Sachs dampers to replace the whole front strut assembly.
• Camber/crash bolts - SPC? OEM? Top, bottom, or both?

Steering:

• OEM tie rod end - necessary as preventive maintenance? Visually they look ok, but I'm fine with replacing to be sure.
• Rack and pinion mount bushing - OEM or aftermarket? Should I go right for the Perrin steering lockdown kit?

Rear suspension:

• Struts being replaced with low mileage Sachs dampers.
• Whiteline subframe bushings, diff mount, outrigger kit
• All remaining bushings to be replaced with OEM

Is there anything I'm missing? I'm on the fence between getting all OEM rear bushings or just getting the whole Whiteline essentials kit instead.



I can tackle some things on my own like the sway bar bushings and end links, but will have a performance shop do the rest of the install so they can do the alignment right there. If I went the OEM bushing route, would it be more economical to just replace things like toe arms entirely in order to save the labor of pressing in new bushings?

[Racecomp Engineering]

You've got a solid plan there!

I would replace the upper mount and an option would be the Pedders offset mounts. Pair that with OEM crash bolts for a good alignment.

I love the feel of the Perrin steering kit but on 2+ hour drives I do start to notice the tiny tiny bit of vibration it adds. I'm going to try the JDM STI bolt + spacer when I get a chance.

I like the Whiteline poly insert bushings but try to avoid full poly bushings. I just prefer rubber or spherical bearings for bushings that move...though I'd consider the whiteline non-adjustable upper arm bushings. You could also do the STI arms kit (trailing, toe, and lower control arm) for full arm replacements with high quality sealed bearings. No extra adjustment over OEM but really nice pieces.

- Andrew

[Capt Spaulding]

Andrew covered most of the bases, but I'll add few things I've concluded working on mine.

First, I'd go with poly (whiteline or ??) sway bar bushings. They added just a touch more roll stiffness to my car. I notice the feel but do not pick up any NVH.

Second, I went with Whiteline rack mount bushings. As with the sway bar bushings I noticed a bit crisper response to steering inputs and no additional NVH that I can detect.

Third, I went with SPC camber bolts (bottom). The shop can get -1.5 on both sides and that is about as far as I want to take a DD/road tripper.

On the rear, I went with the Whiteline's sway bar bushings and diff inserts. I have the subframe inserts sitting in my parts box but for now don't plan to install them. The diff bushings reduced the drive train wind-up and improved shifting a little. It clunks a little on and off the throttle, but that's not a problem.

Other than that, if I were in your shoes, I'd go OEM or STI parts (if I could find them.)

[CTB727]

Thank you, these suggestions have been really helpful.



So if I'm understanding correctly, get new OEM diff bushings and Whiteline inserts to go with?

[Capt Spaulding]

Originally Posted by CTB727

Thank you, these suggestions have been really helpful.



So if I'm understanding correctly, get new OEM diff bushings and Whiteline inserts to go with?

My recollection is replacing the actual diff bushings is non-trivially difficult. I suspect you can probably do fine with the inserts alone.

[Ultramaroon]

Inner and outer rod ends? My lifetime experience with oem-type spherical joints is that I have never seen any go bad unless the boot has cracked to let shit get in. Others may disagree. Just one middle-aged guy's experience with all his extended family's shit-boxes

[RickyRacer]

Originally Posted by CTB727

I'm in the process of refreshing the suspension on my 125k mile 2013 BRZ. Currently the car is stock as it's my DD, but for about 3 years I had it prepped for STX back when I autocrossed it regularly, so it has definitely seen some wear from hard driving.



I've read through Racecomp Engineering's thread to get started but I have some questions.


My car is showing various symptoms of what I can only assume to be worn bushings and components. There is a pull to the left under acceleration at highway speeds, then a pull to the right under deceleration. Steering feel isn't what it used to be, the car feels like it wanders within the lane and I'm constantly having to make steering inputs to keep it centered, etc. Basically feels like a driving on a windy day, but all the time. All wheel bearings have been replaced as well as brake pads, and the rotors and calipers looked fine.



Goal: Get the car to feel like new again, but with an OEM+ setup. I'm fine with a slight increase in NVH as long as it doesn't become race car loud.



So my question is, which parts should I stick with OEM and which are best to go aftermarket? Below is my plan so far, and let me know if there's something I should switch out.



Front suspension:

• OEM front LCAs (in order to to have new ball joints and bushings)
• OEM sway bar bushings
• OEM sway bar end links (driver's side looked rough, possibly causing front end clunk)
• Tie rods - how do I know they're bad? Are they worth replacing as preventive measure?
• Found some low mileage Sachs dampers to replace the whole front strut assembly.
• Camber/crash bolts - SPC? OEM? Top, bottom, or both?

Steering:

• OEM tie rod end - necessary as preventive maintenance? Visually they look ok, but I'm fine with replacing to be sure.
• Rack and pinion mount bushing - OEM or aftermarket? Should I go right for the Perrin steering lockdown kit?

Rear suspension:

• Struts being replaced with low mileage Sachs dampers.
• Whiteline subframe bushings, diff mount, outrigger kit
• All remaining bushings to be replaced with OEM

Is there anything I'm missing? I'm on the fence between getting all OEM rear bushings or just getting the whole Whiteline essentials kit instead.



I can tackle some things on my own like the sway bar bushings and end links, but will have a performance shop do the rest of the install so they can do the alignment right there. If I went the OEM bushing route, would it be more economical to just replace things like toe arms entirely in order to save the labor of pressing in new bushings?

how much are all those bushings gonna cost you in parts? I'm also in a 2013 frs

[Stang70Fastback]

I'm going the scorched earth approach because I'm an OCD idiot, and once I start replacing some things, I tend to replace ALL things. For reference, mine is a 2015 with 113,000 miles. Daily driven for 8 years on god-awful Chicago roads (summer and winter) and many seasons of autocross in STX. I'm actually only doing the front end this year because my approach is... expensive, lol. I am ALSO chasing the "OEM+" route.

I've got 90% of these parts sitting on my garage floor right now and am just waiting on a few last odds 'n' ends.

This list is off the top of my head, in no particular order. For everything I'm replacing, I'm also replacing ALL of the associated hardware (nuts and bolts).

- New OEM front LCAs (these include all the OEM bushings/ball joints which are fine for me).
- New OEM front tie rod ends.
- New OEM sway bar bushings (and new brackets because why not.)
- New OEM steering rack (this is actually because I suspect an issue with my existing rack.)
- New STI steering rack bushings, along with those really long STI bolts for the rack.
- New hubs (because I'd rather not do all this just to have a bearing go bad in short order given the mileage and abuse.)
- New knuckles (because why the hell not at this point - everything else is new.)
- New rotor backing plates and ABS sensors (also an "everything else is new" thing. I'm dumb.)
- ARP studs (never had an issue with the stock studs, but since I have the hubs easily accessible...)
- STI transmission mount (I would do engine mounts but I replaced those at 65k with STI mounts when I did the header and tune.)

I'm also removing and selling my KW V3 coilovers which have 85,000 miles on them and will need a rebuild, and am replacing them with RCE T2s. Now that I have a second vehicle, I'd like a slightly firmer setup. With this comes new rear upper shock mounts (OEM), and I bought new spherical bearing inserts for my front Raceseng camber plates since those were worn out.

That SHOULD result in basically a brand new front end. The only thing I'm not replacing is basically my AP Racing calipers (I AM replacing the pads.)

And for anyone wondering... everything apart from the coilovers came to roughly around $3k.

Also... if anyone here wants a set of V3s for under $1,000 let me know. I'm too lazy to deal with the rebuild stuff, so I'm just going to sell them to someone for a price that should net them a $500-$1,000 savings over buying new once they factor in the rebuild cost.

[orange crush]

Highly recommend the Perrin Steering Rack Lockdown on an older car. I have heard it doesn't make a huge difference on newer ones, but it's great for older cars. The only downside is you do get some engine buzz through the steering. Rev the engine at idle in neutral and you'll feel it in the wheel.

I put it on during an oil change, and it took less time to install than it took the oil to drain, so install time is zero.

[ZDan]

Originally Posted by CTB727

My car is showing various symptoms of what I can only assume to be worn bushings and components. There is a pull to the left under acceleration at highway speeds, then a pull to the right under deceleration.

What are your tire pressures? Because this is *exactly* what will happen if you have a low rear tire. If tire pressures are all good, you might swap the rear tires left/right and see if the pull under acceleration changes from left to right. If it does, one of the rear tires might be "bad" (i.e. internal defects causing it to have higher rolling resistance).

Also, same make/model tires all around, at similar wear levels?

[RACECAR go brrr!]

Originally Posted by ZDan

What are your tire pressures? Because this is *exactly* what will happen if you have a low rear tire. If tire pressures are all good, you might swap the rear tires left/right and see if the pull under acceleration changes from left to right. If it does, one of the rear tires might be "bad" (i.e. internal defects causing it to have higher rolling resistance).

Also, same make/model tires all around, at similar wear levels?

This is a good point. The pull one way under acceleration and the other way under deceleration is how I discovered a half flat tire after I picked up a nail on my way to work before it became a completely flat tire.

Well... it became a completely flat tire 5 minutes later, but it was enough time for me to at least find a safe place to move the car to perform the annoying spare-to-front, front-to-rear swap in the dead of winter in Chicago...

[CTB727]

Originally Posted by RickyRacer

how much are all those bushings gonna cost you in parts? I'm also in a 2013 frs

So far I'm just at $2k, but that includes other maintenance items that I was replacing at the same time such as brake pads, wheel bearings, and a couple of under tray pieces, various nuts and bolts, etc.



So far I've bought:


OEM Front LCAs
OEM Front sway bar end links
OEM Front sway bar bushings


STi steering bushing and extended bolts


Whiteline diff insert
Whiteline subframe inserts
STi lateral link and trailing link set (shipping hurt me on this one)
OEM Rear sway bar bushings
OEM Rear sway bar end links
Used OEM rear UCA
Whiteline bushings for rear UCA


Set of low mileage Sachs dampers from a 2017

Originally Posted by Stang70Fastback

I'm going the scorched earth approach because I'm an OCD idiot, and once I start replacing some things, I tend to replace ALL things. For reference, mine is a 2015 with 113,000 miles. Daily driven for 8 years on god-awful Chicago roads (summer and winter) and many seasons of autocross in STX. I'm actually only doing the front end this year because my approach is... expensive, lol. I am ALSO chasing the "OEM+" route.

I've got 90% of these parts sitting on my garage floor right now and am just waiting on a few last odds 'n' ends.

This list is off the top of my head, in no particular order. For everything I'm replacing, I'm also replacing ALL of the associated hardware (nuts and bolts).

- New OEM front LCAs (these include all the OEM bushings/ball joints which are fine for me).
- New OEM front tie rod ends.
- New OEM sway bar bushings (and new brackets because why not.)
- New OEM steering rack (this is actually because I suspect an issue with my existing rack.)
- New STI steering rack bushings, along with those really long STI bolts for the rack.
- New hubs (because I'd rather not do all this just to have a bearing go bad in short order given the mileage and abuse.)
- New knuckles (because why the hell not at this point - everything else is new.)
- New rotor backing plates and ABS sensors (also an "everything else is new" thing. I'm dumb.)
- ARP studs (never had an issue with the stock studs, but since I have the hubs easily accessible...)
- STI transmission mount (I would do engine mounts but I replaced those at 65k with STI mounts when I did the header and tune.)

I'm also removing and selling my KW V3 coilovers which have 85,000 miles on them and will need a rebuild, and am replacing them with RCE T2s. Now that I have a second vehicle, I'd like a slightly firmer setup. With this comes new rear upper shock mounts (OEM), and I bought new spherical bearing inserts for my front Raceseng camber plates since those were worn out.

That SHOULD result in basically a brand new front end. The only thing I'm not replacing is basically my AP Racing calipers (I AM replacing the pads.)

And for anyone wondering... everything apart from the coilovers came to roughly around $3k.

Also... if anyone here wants a set of V3s for under $1,000 let me know. I'm too lazy to deal with the rebuild stuff, so I'm just going to sell them to someone for a price that should net them a $500-$1,000 savings over buying new once they factor in the rebuild cost.

This is almost the approach I took because I'm also OCD, but decided to hold off on a few things for the time being. Going to leave tie rod ends alone for now. I almost bought a new subframe just to get new bushings, but enough people talked me out of it so I'll see how the inserts perform lol.

Originally Posted by orange crush

Highly recommend the Perrin Steering Rack Lockdown on an older car. I have heard it doesn't make a huge difference on newer ones, but it's great for older cars. The only downside is you do get some engine buzz through the steering. Rev the engine at idle in neutral and you'll feel it in the wheel.

I put it on during an oil change, and it took less time to install than it took the oil to drain, so install time is zero.

I ended up getting the STi steering bushing and extended bolt kit. We'll see how it turns out once I get it installed.

Originally Posted by ZDan

What are your tire pressures? Because this is *exactly* what will happen if you have a low rear tire. If tire pressures are all good, you might swap the rear tires left/right and see if the pull under acceleration changes from left to right. If it does, one of the rear tires might be "bad" (i.e. internal defects causing it to have higher rolling resistance).

Also, same make/model tires all around, at similar wear levels?

Originally Posted by RACECAR go brrr!

This is a good point. The pull one way under acceleration and the other way under deceleration is how I discovered a half flat tire after I picked up a nail on my way to work before it became a completely flat tire.

Well... it became a completely flat tire 5 minutes later, but it was enough time for me to at least find a safe place to move the car to perform the annoying spare-to-front, front-to-rear swap in the dead of winter in Chicago...

This was the first thing I checked. Tires are Bridgestone Potenza Sport with about 4,000 miles, pressures are 34 psi all around. Swapped left and right tires and had the exact same symptoms--no change in direction of pull.



I've been replacing suspension bits a little at a time and the first thing I replaced was front sway bar end links and front sway bar bushings. Strangely enough the pull seems minimized, but it's still there. My front end clunk went away however, and the steering feels more connected. Not surprising, considering one of the end links was completely shot.


I'm speculating that the major culprit in this instability issue has to be rear upper arm bushings. Another symptom is when taking sweeping on ramps at higher speeds (pushing it maybe 7/10ths at most), the rear end feels very unstable. By giving just a bit more steering input mid turn (but not jerking), the car feels like it wants to snap. Haven't confirmed, but it feels like the outside rear wheel toes out under this scenario.