Hey all-

I started out the day getting ready to change out the lower universal joint in the steering column of my '86 745T. The symptom was a clunk when turning the wheel off center, and the tie rod ends and radius rod bushings had just been done. Looked at the universal, it looked like a recent replacement. Shiny like mine, with undercoat still on the rest of the column.

Now that I had the car on stands, I turned the wheel back and forth. Knocking came from the steering wheel, right around the upper column bearing. I had wondered if that's where it could be, as I heard a clunk from that area before.

I pulled the wheel, stalks, horn ring & plate. I tried removing the snap ring with a set of needlenose, no luck. I put everything back on and drove to get a snap ring plier set.

Driving along, I hear this odd buzzing/rattling sound between 2K and 3.5K rpm. Push in the clutch, noise goes away. Definitely climbs in tune with the motor during that speed band, and it's always quietly present at other motor speeds. I figured it's a loose stalk screw.

So I get the tools, take it all back apart, pull the snap ring. Remove a poly-plastic bushing, which sits on a metal washer/spacer. Under this I find what looks like a roller-type bearing, so I loaded it up with a little wheel bearing grease. I cleaned up the rest, re-installed everything, and drove off.

Buzzing/rattling is still there. Thunk from column is GONE.

So after repeatedly tightening, removing, and cursing various stalks, horn rings, and wiring harnesses, I've gotten to the point where I drove the car after removing the stalks, horn ring & plate, snap ring, poly-plastic bushing & metal spacer, and simply placing the wheel back on unbolted. Removal of all of these items AND the wheel for few seconds (quiet neighborhood, except for me) made NO change.

So the car steers nicely, front end is nice and tight, motor's humming along, it's nice out, and all I hear is BZZZZ. It kind of sounds like playing cards in a kid's bike wheel. Real pleasant.

So I could very well find myself at the dealer with this one, I could drive the car with the occasional thunk but not like this. If anyone has a theory they'd like to try out on me, I'm game. I've tightened all the bolts I could find on the dash subframe and column lock assembly. I'm stumped.

Thanks for reading this far-
-Dylan

As I recall, there was a Volvo TSB on the steering column bearing to fix this problem. As for the buzzing, I know how tough these can be. Try using a rubber hose stuck in your ear to locate the sound more precisely, then work from there.

Found it! I discovered the noise was completely motor-related- Loudest at 2600 rpm. I stuffed myself in the driver's footwell upside down and reved the motor- it was easy to tell when I hit 2600 rpm. Funny little buzz coming from the ignition ECU area. I pressed and pulled anything in sight, and some things out of sight, and began to think it was inside the defroster duct. Ugh. I thought it could have been inside the cowl ahead of the windshield, so I smacked that with my hands a few times. No difference. Then I spotted a loose bolt that fastens the A/C hose bracket that secures the hose to the firewall directly in front of the driver. The washer was vibrating- removed the bolt, no more buzz! So that's tightened back down and will be watched closely.

Good thing, as I'm about to leave for Philly. Now only the traffic will drive me nuts.
-Dylan

Steve- thanks for the feedback-
When you mention 'this problem' are you referring to the clunk? Or the buzz/rattle? I'm assuming you meant the clunk. I'll go see what I can dig up at Volvo's tech site.

I'm thinking a mechanic's stethoscope is in order, I'll let you know what I find out if I don't get committed first.

Thanks again-
-Dylan

I Know you started out doing steering column work, but then you said...

"Driving along, I hear this odd buzzing/rattling sound between 2K and 3.5K rpm. Push in the clutch, noise goes away. Definitely climbs in tune with the motor during that speed band, and it's always quietly present at other motor speeds. I figured it's a loose stalk screw."

This sounds like a clutch problem, either the throwout bearing or the pilot bearing. You may have simply found another completely unrelated problem while working on the steering. ( This is the kind of luck I have!!)

I would investigate this. Also, thanks for the tip on lubing the column bearing. I'm going to do that the next time I'm there!!

"This sounds like a clutch problem, either the throwout bearing or the pilot bearing. You may have simply found another completely unrelated problem while working on the steering. ( This is the kind of luck I have!!)"

Thank goodness you were on the right track- I was hoping it wasn't clutch-related. Turns out the noise was completely RPM related- 2600 rpm, driven or parked.

Finally- after checking a few things- I spotted a loose bolt that fastens the A/C hose bracket that secures the hose to the firewall directly in front of the driver. The washer was vibrating- removed the bolt, no more buzz! So that's tightened back down and will be watched closely.

Good thing, as I'm about to leave for Philly. Now only the traffic will drive me nuts.
-Dylan

Hey I hope that tip makes it's way to the FAQ. Guess once I figure out the rest of this I'll submit it.

The noise could be a different system altogether, wouldn't surprise me one bit. The noise definitely sounds like it's coming from under/in the instrument cluster area, though.

The weird part is this morning while driving to breakfast I noticed the noise seems to have reduced somewhat, with the loudest noise coming on while engine braking through the 3.5K to 2K rpm band. The fun never stops.

Thanks for the suggestion-
-Dylan

You have all my sympathy.
Don't know the answer, just keep on searching.

I tell you a story, what happened to a friend of mine:
He heard a tzz - tzzz - tzzzz with every tire-wheelspin
according to speed. But can only hear it at low speed.
After several days and various mechanics, it turns out,
in the little ring, where the balancing weight is mounted,
there was some sand (maybe that side of the wheel had no balancing weight)
and that sand ran around and down the rim and made the sound.
One deep breath and puhhh-it was gone. Yo!