Suspension Dilemma: Overly Harsh Ride

[turbomoose]

Hello again all! Within the past few months I've noticed that my trusty 850's ride quality has become a bit too harsh for my liking. After driving my mothers '04 S40 LSE for a few days, I grew comfortable with its more forgiving, but still flat around sharp corners suspension. I returned to my 850 today and was very shocked at how harsh the ride actually was. Every expansion joint on the highway, every little imperfection in the road, was extremely harsh. After researching for a few hours, I think my problem lies on my control arms.

Now after the ScanTech spring seat fiasco a few months back, I thought my suspension problems were behind me. Well, I was wrong apparently. Just today I learned that my control arm bushings were more than likely needing to be replaced. You see, I torqued the control arm to subframe bolts to spec while the car was in the air. Common sense escaped me I suppose. In that process Im sure I damaged the bushings once the suspension was loaded. Not that it really matters because they (control arms) were more than likely shot to begin with.

Now, my question to you all is, do you think, or know, that if I replace my entire control arms with either the "stock" control arms offered by FCPGroton: FCPGroton Control Arm & End Links OR the upgraded control arms with Delrin bushings: QBM Control Arms that this will cure the impact harshness as stated in the product description of the QBM Control arms? Has anyone had any similar experience? If so, what should I do first when it comes to replacing suspension parts to cure the harshness?

I might also add that I intend to replace the struts, which are starting to show signs of oil seepage in the very near future. Im thinking of Bilstein TC. I would like to correct the harshness, which Im pretty sure would not be caused by aging struts first. My end links, strut mounts & spring seats have been replaced within the last 3 months with genuine volvo parts, but I do plan to replace the end links with ipd's HD end links when I replace my control arms.

Please, Id like all input as this is really taking the joy out of driving my 850.

Thanks again for the support!

-Nathan

[matt1122]

I went with the stock control arms and because the quality had been so harsh when they needed replacement I was incredibly smiley and happy afterwards. I think you'll be satisfied either way, and unless you're comparing it to something you may not notice the difference.

Note that this is the way I felt with the sport suspension that came on the T-5R.

[turbomoose]

My cars mulroney form (Window sticker) says that it has the optional sport suspension, which according to the brochure that came with the car says that it's standard on the 850R. But I've NEVER noticed it being so harsh until recently.

[matt1122]

My cars mulroney form (Window sticker) says that it has the optional sport suspension, which according to the brochure that came with the car says that it's standard on the 850R. But I've NEVER noticed it being so harsh until recently.

Probably because you just recently busted the control arms.

[turbomoose]

When I installed the volvo brand spring seats, after replacing 3 sets of scantech spring seats I read in a Haynes manual (Page 10-7 Illustration 5.2) that the springs must be compressed to aprox. 11.81 inches prior to installation, and of course the spring ends must be located correctly in the upper and lower seats. I did not ensure this measurement. I simply compressed the spring enough to remove the strut mounting nut, remove and replace the parts, then decompressed the spring and made sure the spring ends sat perfectly in the spring seat and strut.

Could that be why it's so harsh 3 months later?

[GT2]

When I installed the volvo brand spring seats, after replacing 3 sets of scantech spring seats I read in a Haynes manual (Page 10-7 Illustration 5.2) that the springs must be compressed to aprox. 11.81 inches prior to installation, and of course the spring ends must be located correctly in the upper and lower seats. I did not ensure this measurement. I simply compressed the spring enough to remove the strut mounting nut, remove and replace the parts, then decompressed the spring and made sure the spring ends sat perfectly in the spring seat and strut.

Could that be why it's so harsh 3 months later?

No

[turbomoose]

I hope you're right! Thanks GT2

I wonder why they print that spec.

Does anyone know?

[SteveO]

In january installed kw V2's, hubs, strut mounts, spring seats, control arms, and tie rod ends I got from ipd during a sale. During a rencent engine swap I discovered one control arm balljoint seemed bad (almost frozen), and one tie rod end also seemed bad (very loose)

Both problems were on the drivers side, I had not hit anything but had been hearing a clunk before the engine swap.

I think it's possible that the mechanic damaged them on the install, or the parts were bad to begin with.

I don't know if they were oem or scantech

Bottom line check the parts for quality before the install because even if you get free replacement parts the labor is the $$$$.

[turbomoose]

Yeah, exactly! I learned my lesson with the scantech spring mounts! I'll only buy original volvo parts, or parts that has a high consumer rating. Like Bilstein, Koni, QBM.

I dont know about IPD's stuff yet. Heard some good, heard a lot of bad. :huh:

[SteveO]

Yeah, exactly! I learned my lesson with the scantech spring mounts! I'll only buy original volvo parts, or parts that has a high consumer rating. Like Bilstein, Koni, QBM.

I dont know about IPD's stuff yet. Heard some good, heard a lot of bad.

I just got off the phone w/ Daniel @ IPD he didn't know who the made the parts I bought But They were technically out of warranty send them back and they would look at them and let me know.

[GT2]

I hope you're right! Thanks GT2

I wonder why they print that spec.

Does anyone know?

Its probably just to give you an idea of how far to go, to get the tension off the unit.

[turbomoose]

Its probably just to give you an idea of how far to go, to get the tension off the unit.

But it says to compress it to that measurement then install the spring seat, strut mount and retaining nut. Then decompress the spring fully, making sure it's seated correctly.

[erikv11]

But it says to compress it to that measurement then install the spring seat, strut mount and retaining nut. Then decompress the spring fully, making sure it's seated correctly.

They have to give at least some spec. If you overcompress (imagine going to something like 9 inches) then the car will sit lower. And probably the ride will be much harsher because you are sitting on compressed springs that can not absorb any shock (remember, struts and shocks only dampen the bounces, they do not do much absorption).

If the spring is undercompressed (imagine 13 inches) then the unit won't assemble together. Or if it would, the weight of the car would compress the springs down and you'd have a gap between the star-shaped nut and the spring seat.

The 11.81 inches (which is exactly 30 cm, by the way) is probably some combo of spring strength and body weight, my guess is that it is the length where the spring is almost, but not quite, compressed to the length where it sits with the weight of the car on the spring.

[Mr. Norm]

I just had the QBM control arms installed in my 96854t5. They make a huge difference and I strongly suggest them. Much better than OEM, I am very impressed.

[turbomoose]

I just had the QBM control arms installed in my 96854t5. They make a huge difference and I strongly suggest them. Much better than OEM, I am very impressed.

Great! Huge difference in what tho?