'96 855R, Feel a clunk in the steering wheel

[regent]

...Cure was retorque subframe
...

Could you specify which SF fasteners you had to re-torque and to what value?
Thanks

[MrPc]

Ddantz, that's very interesting about retorquing the sub-frame.

My suspicions had been leaning towards radial play in the rack, but lately I've discovered an intersection in town that reliably makes the steering wheel move--not just the "normal" slight clunk you feel, but a more pronounced movement fore/aft movement in the wheel. The intersection is a right turn traffic island at a light, with a raised crosswalk/speed bump. If I need to yield, the car comes to a stop with the front wheels on top of the bump. I get a clunk on the way up stopping, and another one on the way down when I leave.

The fact that I can feel fore/aft play in the wheel suggests that the rack could be moving relative to the dash. I'm going to try retorquing the subframe bolts this weekend. I'll keep you posted...

[MrPc]

Update: I re-torqued the subframe, and have driving the car about 2500 miles. What I can say is this: while the clunking has not disappeared, the conditions on which the clunking occurs have changed. It seemed to have stopped for the first little bit, and no longer occurs when starting into a turn after being stopped. It is more likely to happen now when reapplying power after coasting down or braking.

When I removed the passenger front subframe bolt, I found a small amount of honey colored fluid, similar to what xHeart posted in this thread: https://www.matthewsvolvosite.com/forums ... ilit=honey Anybody have any idea what this liquid might be, or where it came from?

Also, when I removed the passenger rear subframe plate, I found a few polished surfaces that suggested that there may have been a small amount of movement--like maybe one or two millimeters. The mounts themselves seemed fairly solid, many small small cracks but not trashed. When I put a screwdriver in them and tried to flex it, they moved smoothly, similar to a new mount.

Anybody have any ideas? Should I change the subframe mounts?

Paul

[regent]

Update: ...When I removed the passenger front subframe bolt, I found a small amount of honey colored fluid...

When I was installing the IPD SF bushing insert kit I had similar findings with the RH front, however did not read much into it; looked like mixture of muddy water and rust to me altogrther.

[MrPc]

Update: It's fixed. The clunks are gone.

The culprit was dried up grease inside the steering column, on the steering column mount, and inside the steering column bearing.

I discounted the steering rack, subframe mount and control arm theories because the clunks were not felt at the moment when engine or torque steer forces changed, but some random time after that, if at all. When I looked at the subframe bushings, I realised that they are fairly soft so some small amount of subframe movement would always occur with those changing forces. As the steering rack is on the subframe, and the steering wheel is fixed to the dash, there needs to be flex in the linkage between them as the subframe changes position. The real ah-ha moment came though, when I I noticed that the character of the clunks changed with different tilt-a-wheel steering wheel positions.

To fix it, do this:

1. Remove the under-the-dash panel: 3 T25 screws.

2. Crawl under, so that your head is near the gas pedal, and look up. If you rock the steering wheel back and forth, and you'll see that the whole assembly isn't especially rigid, but it all flexes with the only real fixed points in the assembly being the pinion on the rack, and the clamp bolt for the tilt-adust. The support for the sleeve at the bottom of the column isn't especially rigid, the steering column bearing floats on the shaft and its rubber mounts, and the end of the shaft slides in and out in the upper column. Stiction on any of these causes the mechanism to bind up momentarily until the turning forces over come it; the sudden release is the clunk you feel. If you rock the wheel back and forth, you will probably hear sounds that remind you of the familiar clunk.

Unclamp the steering wheel and push it all the way in. This pushes the lower column sleeve all the way into its mount. Wipe off the old dried up grease off the sleeve and apply some low temperature sticky grease.

Apply grease to the outside of the upper column sleeve. This sleeve forms the pivot point of the steering wheel tilt.

Small_0002_text.JPG (51.53 KiB) Viewed 3039 times

2. Remove the retaining pin on the upper universal joint. Remove the safety clip, then hold the head with a 10mm box end wrench and unscrew the nut (13mm). Once removed, mine came apart easily.

Remove the upper u-joint from the lower steering shaft.

Small_0001_text.JPG (61.05 KiB) Viewed 3039 times

3. Now that the u-joint is undone, the lower steering shaft can move in and out of the upper column freely. Unlock the steering wheel clamp and pull the wheel out all the way. Fold the joint out of the way and you can pull the shaft out further, but don't pull it out too far. If you do, it will come out all of the way, and you will have to put it back in exactly the same to avoid ending up with a cockeyed steering wheel. I made marks on mine beforehand in case this happened. When it's almost all the way out, remove the old dry grease, apply low temperature sticky grease, and shove it back in.

Apply grease to the splines on the upper end of the of the lower steering shaft. Slide it out as far as you can without removing it from the upper column. The photo shows red grease in the wrong place on the shaft because on my first attempt I tried to grease it without removing it first.

Small_0003_text.JPG (53.06 KiB) Viewed 3039 times

4. Remove the lower steering column bearing by pulling up the outer rubber cover, removing the lock ring and then the lower/inner rubber cover. Extract it from the lower steering shaft to expose the needle bearing in the middle of it. Clean off the old grease--if there is any--and pack it with low temperature sticky grease. Mine was almost completely dry, loose, but not squeaking.

Pack the needle bearing in the steering column bearing with grease.

Small_0004.JPG (63.19 KiB) Viewed 3039 times

This pdf, courtesy of another thread, describes the steering column bearing and how to remove/replace it, starting in about the middle of it.

850 steering column.pdf

(715.54 KiB) Downloaded 3162 times

5. Put everything back.

That's all there is to it. On my car, the steering clunks disappeared, and the steering has a solid, viscous and smooooth feel it didn't have before.

I wonder if the 96's seem to have the clunk, while others don't might be explained by different kinds of grease being used on the assembly line during different periods. Or perhaps the autoworker during that period wasn't applying as much.

Many thanks to everyone for their ideas in this and other threads that helped lead to the solution. I started this thread almost a year ago!

Paul

[dosbricks]

Wow Very interesting and very good sleuthing. I love this forum because it always finds repairs for me to do that I had no clue about how to do, and often even a clue where to begin.

Good work, Paul, and thanks!

[smokky]

Helpful thread thank all you guys