Violent steering shake 55-70mph 95 q45t

[GseaQ]

Well, a couple of weeks ago I turned the key to start and nothing - not even a click. I changed the starter relay - still nothing. So I call the towtruck. It was a flatdeck with a winch to pull the car up onto the tilted deck. When I got the car back I felt the shimmy - the steering wheel would move a good inch or inch and a half violently between 55 and 70 mph. Slowing below that made it stop. Driving over that seemed to change it to a gentler cyclical "shudder" every second or 2. I had the original BBS 15" wheels with pretty new Michelin Pilot Alpins on it then. Since then I put the 18" x 8" 2004 Q45 Premium wheels and 255/40x18 Michelin Pilot Sports on it. The shimmy remains the same.

I looked at the tension rod bushings and they are weather cracked. Since this happened immediately after the towtruck ride I figure the driver must have hooked onto something he shouldn't have and bent it, but what? I'll get under it today for a look at the tie rods and everything else. I mention tie rods because it seems to have enough toe-out to see with the naked eye, which I think must be too much.

It's got the Eibach's, Tokiko blues, the upper links were tight a year ago, so even though they may have worn since then, I doubt they were involved in the towtruck hookup.

Does anybody have any ideas?

Thanks,Glenn

[qship96]

A competant alignment technician will identify any worn parts while returning the alignment to factory specs.

[fixer]

IF YOU got enough toe out to see, the tow truck driver could have hooked it to the tie rod ends and bent that, turn the wheel all the way to the stop and inspect each tie rod ends. if that is not the problem, you can check the rack bushings, The bushings can deteriorate with age and can cause the rack to move around

[GseaQ]

IF YOU got enough toe out to see, the tow truck driver could have hooked it to the tie rod ends and bent that, turn the wheel all the way to the stop and inspect each tie rod ends. if that is not the problem, you can check the rack bushings, The bushings can deteriorate with age and can cause the rack to move around

Yeah, that's what I was thinking. The car is so low that he couldn't see very well under when he was hooking up, but that doesn't excuse him if he wrapped the chain around the tie rod(s). The rack was transferred over from our old '92 a year and a half ago and the bushings were either fine or replaced at that time (can't remember now), but definitely worth a look. Do you think hooking around the tie rod would trash the rack bushings?

Thanks guys.

[fixer]

i dont think the tow truck could have damaged the rack bushings, but bent tie rod ends are a common occurence around here

[GseaQ]

So, while I am hopeful the rack bushings are not at fault, do you think a bent tie rod combined with worn tension rod bushings could cause such bad shimmying?

[maxnix]

Difficult to imagine not using new rack bushings. When they are worn, they allow lateral movement as they are glazed on the interior rack side.

I replaced mine with SPL polyurethane bushings.

[qship96]

Did they feel any different Brian?

[maxnix]

Not to me, but I am numb. Did it mainly for durability.

[Q45tech]

Rack bushing like all rubber bushings last 7-10 years unless abused by an oil sensor leak or other petrochemical fluids. That is good durability to me.

[GseaQ]

OK, just to touch base with you guys, I got new Tension Rod bushings and Steering Rack bushings from IOS. I'll change one or the other first and check the results. I don't just want it fixed. I want to know WHAT fixed it.

[fixer]

just the fact that the toe is out enough to see with the naked eye will cause some shimmy the faster you drive. make sure the inner tie rods are straight and fix the toe problem. then take it for a drive. if tension rod bushings and rack bushings look good then they probably are not the cause of your problem but it is a good idea to replace them anyway.

[GseaQ]

Thanks, I tried to get the tension rod bushings installed yesterday, BUT the ones I got were too small. Somehow my car seems to have gotten "Active" model tension rods. The correct ones should be here by next Friday. My plan was to replace the tension rod bushings first and test, then the steering rack bushings and test and finally get a wheel alignment.

Glenn

[goody90q45]

Did you by chance measure the bushing inside diameters? I have a set of 54476-35F20 bushings with a 14mm ID. I believe they're for the base model. Having active tension rods and getting the wrong bushings has happened to a few owners. I got mine from a club member who's the owner of a 90Q.

[maxnix]

Save time and change all four bushings at once. Really. If your upper links, ball joints, lower arms and end links are good, then get an alignment. This means your rear suspension must also be perfect to achieve the required 0.0° thrust angle to perform the alignment.

Don't neglect anti-sway bar bushings and end link bushings for precision controlled handling.
Modified by maxnix at 9:18 AM 5/26/2009

[GseaQ]

Thanks Mike, but it was the -35F20's that they sent me, so I must have the "Active" rods.

Brian, I appreciate the time saving aspect, but I really want to do one thing at a time and see the result, even if I end up changing other stuf before I'm finally done.

[GseaQ]

OK, update time. Replaced the tension rod bushings one day and the steering rack bushings the next.

The old tension rod bushings were cracked radially but not leaking. The new bushings tightened up the suspension noticeably, but didn't cure the shimmy.

The new steering rack bushings made a bigger difference to the point that the car is now drivable between 55 & 70. BUT the shimmy is still there - just significantly less severe. We figured out that the ones we took out had about 375,000 kms on them. They still LOOKED great!

What we found - the upper links are SHOT!!! So much so, they could very well be original. With the suspension hanging, you can rock each front wheel in and out at the top and bottom. You can see and hear the movement at the outer end of each upper link.

What is really strange - there was not and is not any creaking noise from the upper links when going over bumps. I've driven with worn upper links before and the noise is very distinctive and, I thought, ALWAYS appeared with worn out upper links. Go figure. I'm ordering more from IOS tomorrow.

Glenn

[Q45tech]

What one learns after 19 years in owning one Q is that everything except the engine wears out multiple times.

I've had 8 sets of upper links.I've had 5 sets of tension rodsI've had 2 sets of lower armsI've had 2 sets of third linkI've replaced the hubs, bearings, everythingI;ve had 3 sets of rack bushingsI've had 3 sets of engine mountsI've worn out [bent out of spec] 3 sets of oem wheels

Besides the engine the only things as built in engine compartment is the power steering pump and rack, brake vacuum booster, the fuse panels, the wiring, the at resistor.

I always test my wheels without tires every year to make sure they are still in spec [no more than 5 grams per side needed to get to 0/0. grams

[GseaQ]

So, the trashed upper links have been replaced, along with steering rack bushings, tension rod bushings, front rotors, pads and calipers. Every component replaced so far has made some improvement - slightly tighter feel to the suspension and steering each time, BUT the core vibration problem is STILL there, especially bad with light to moderate braking from 75 mph down to 60 mph. Looking at the suspension design, the remaining wear components are, tie rod ends, ball joints (incorporated into the lower control arms?) stabilizer bar bushings and kingpin bearings (kingpins, too?).

The tie rod ends and ball joints are tight. The stabilizer bushings are worn and there is visible play in the driver's side kingpin/bearings. I've ordered the kingpin bearings (both sides) from IOS. Hopefully that'll kill the remaining vibration.

I'll let you know what happens next.

Modified by GseaQ at 8:18 PM 6/10/2009
Modified by GseaQ at 8:20 PM 6/10/2009

[maxnix]

Great reporting!

You will soon follow Q45tech's example and be all the better off for it.

[GseaQ]

Hopefully, better late than never. This was happening with the wheels and tires that cam with the car - 255/40x18 Pilot Sport summers on 2004 Q45 18x7.5 (or 8", whichever was the widest option in '04) chrome wheels. Well, whoever mounted those tires included about a QUART of water with the air! Compressors need to be drained occasionally!

I have discovered the best tires I ever put on a Q45 - Pilot Sport PS2. They have asymmetrical tread for corner to corner rotation, they are sticky and THEY ARE QUIET.

[Q451990]

Thanks for letting us know!

Heath

[mattd1979]

GseaQ, did you actually press out the old tension rod bushings or did you replace the complete assembly? I'm looking at just getting the bushings due to the price but not quite sure what tool I will need to press out the old and press in the new bushings.

Matt

[GseaQ]

GseaQ, did you actually press out the old tension rod bushings or did you replace the complete assembly? I'm looking at just getting the bushings due to the price but not quite sure what tool I will need to press out the old and press in the new bushings.

Matt

Hi Matt,

I just bought the bushings and had them pressed in. My friend had a well equipped shop did it for me. He used a hydraulic press. Pretty straightforward. He said one old one came out easy and the other one took quite a bit of pressure. Make sure you measure your old ones (diameter) before you order. Mine were the smaller diameter Active model bushings on my non-Active car.

Cheers,
Glenn