[Robertbweltzien]

I just bought both front strut complete assemblies (KYB SR-4596 and SR-4597, Monomax tubes), both rear shock absorbers (KYB 349244, Excel G twin tube) and two rear shock mounts (KYB SM-5850) from RockAuto for my Georgia built '12 SX turbo with 120K miles. With tax, shipping and a 5% April discount the bill came to $447. Knock off another $75 with a rebate from KYB. Total cost under $375. I figured that replacing the whole strut is the way to go considering how bad the roads are here in CT and the Monomax tube should restore original ride quality.

 

[Turbonut]

Good luck. I still have the OEM struts on the '11 2.0T (224,000 miles) and it rides just as crappy as when new. I used to say the car rides like a truck, but our Ford 4x4 actually rides better than the Kia. Last year thought I'd try the FCS assemblies on the front, no difference, so took the them off after 50 miles and they're still sitting in the garage.

 

[Robertbweltzien]

A bit of rattle out of the front but the control arm bushings, ball joints, tie rod ends and stabilizer bushings were all good so I figured an inexpensive warmover with a lot of new parts was a good risk, maybe it will handle the washboards better without as much rear kick. Yeah, I wouldn't expect ride comfort to improve with these cars unless a complete and competent aftermarket kit was installed. The front ends on these cars are nothing like that on Hondas and they certainly went the cheap way out. I wouldn't be surprised if the rattling in most of old KIAs comes from broken spot welds. I do have KYBs on my old Linc Mark VII that I put on nineteen years and 110K miles ago and they still ride quite nicely so I hope their quality hasn't tanked.

 

[KingFatty]

Interesting, on my 2012 SX with 120K miles (mostly highway), my ball joints were loose/sloppy and my control arm bushings were shot/torn. Maybe the rattle is from something that is deceptively loose, seems good on inspection but rattles during driving?

 

[Turbonut]

We have a long stone driveway and over the small irregularities there was "rattle" that drove me nuts, that's why the FCS strut assembles only have <50 miles, just used them for a test. Long story short, it was a loose connection at the bottom of the steering column that attached the steering shaft to the rack. Now one would believe that it could have been heard inside the cabin, but in this case it wasn't.

With 224k miles, over the years, replaced the inner and outer tie rod ends, in fact 2 sets of the outer as the Mevotech I purchased with a lifetime warranty were shot after 42k miles, so were replaced no cost, but I still had to do the install and alignment. Ball joints were shot, one completely loose, other marginal, but the bushings were in great shape.

 

[Robertbweltzien]

Interesting, on my 2012 SX with 120K miles (mostly highway), my ball joints were loose/sloppy and my control arm bushings were shot/torn. Maybe the rattle is from something that is deceptively loose, seems good on inspection but rattles during driving?

Very slight clunk, a feeling that something is loose. Still handles fairly tight but rides like a go cart and the back kicks out in turns over bumps. No rack or tie rod play and no movement felt in the ball joints and no noticeable movement at the control arm mounts when prying all with the car in the air. New front tires 20K miles ago with normal wear. I've always done shocks and/or struts on any car with >100K miles, except my old Accord. With the old struts out I can recheck the control arms. I have KYBs on my '89 Mark VII that are still good after 18 years. $375 for complete strut assemblies and shocks was too good to pass up. I don't expect much ride improvement but I should be safer. Already replaced all the brake rotors and calipers. Bought the car off GF last year for $3K. She was wise to get rid of it. I knew I'd end up putting $3K in parts to make it a reliable daily driver.

 

[Robertbweltzien]

We have a long stone driveway and over the small irregularities there was "rattle" that drove me nuts, that's why the FCS strut assembles only have <50 miles, just used them for a test. Long story short, it was a loose connection at the bottom of the steering column that attached the steering shaft to the rack. Now one would believe that it could have been heard inside the cabin, but in this case it wasn't.

With 224k miles, over the years, replaced the inner and outer tie rod ends, in fact 2 sets of the outer as the Mevotech I purchased with a lifetime warranty were shot after 42k miles, so were replaced no cost, but I still had to do the install and alignment. Ball joints were shot, one completely loose, other marginal, but the bushings were in great shape.

O

 

[Robertbweltzien]

We have a long stone driveway and over the small irregularities there was "rattle" that drove me nuts, that's why the FCS strut assembles only have <50 miles, just used them for a test. Long story short, it was a loose connection at the bottom of the steering column that attached the steering shaft to the rack. Now one would believe that it could have been heard inside the cabin, but in this case it wasn't.

With 224k miles, over the years, replaced the inner and outer tie rod ends, in fact 2 sets of the outer as the Mevotech I purchased with a lifetime warranty were shot after 42k miles, so were replaced no cost, but I still had to do the install and alignment. Ball joints were shot, one completely loose, other marginal, but the bushings were in great shape.

It's reassuring to know that you have 224K on your Optima. It certainly makes me confident that I can drive mine for at least several more years.

 

[Turbonut]

It's reassuring to know that you have 224K on your Optima. It certainly makes me confident that I can drive mine for at least several more years.

May have 224k miles, but it surely keeps my mechanical know how up to date as many parts have needed to be replaced and as some where
rusted solid, had to be cut out. Another A/C compressor will be replaced probably next month.
Good luck

 

[Robertbweltzien]

Turns out the struts from RockAuto are incorrect and have to be sent back. My SX was built in Georgia on 10/25/11, the month before they changed the position of the stabilizer link mount on 11/30/11. None of the major suppliers list the parts. Open mouth, insert foot!

 

[Robertbweltzien]

Bought the shorter end links (Moog) and installed the "wrong" struts. Perfect, except for no mount pad for the antilock brake wire. Then again, it should be fine where it is. I am quite pleased with the result and the car now rides noiselessly. The previous owner wants to drive it now!