I own two volvos, a 96 850 and a 07 S40. Love them both. Have some technical questions re the 850 and a seemingly unresolvable steering wheel shudder when driving over 80Km/h. All tyres, wheels and brakes have been eliminated from the equation. I am wondering about sway arm bushings. The vehicle has been cared for by authorised Volvo mechanics and yet they seem unable to find the problem. A tyre mechanic though he had solved it but it has come back. Funny thing is it is quite intermittent. Look forward to hearing a response. H

 

Hello Mate,

Greetings from Chicagoland, U.S.

>All tyres, wheels and brakes have been eliminated.

It is annoying to have intermittent problems, I understand. I doubt it's brakes, unless shudder occurs under braking. As to the wheels, they are probably ok, as long as you don't see obvious bends/out of roundness.

As for tyres, I assume you made certain that both fronts are of same brand/size, tyre pressure corrected and the treads left about the same amount. Balance is probably ok too, as they usually occur at certain speeds, usually under 100km/h, but it wouldn't hurt to double-check them, unless your technician did it already with a dynamic balancer. Or, the balance weight (s) might have been thrown away, which happens though not too often.

As you guessed it, it might be somewhere in the front suspension. I would check the following:

1. Upper spring seats (noticed by clunking noise).
2. Ball joints (look for damaged dust boots & free play).
3. Sway-bar link rods (look for damaged dust boots & free play).
4. Sway-bar bushings, as you mentioned them.
5. Control arm bushings (check for free-play or eteriorated bushings).
6. Tie-rod ends for free play.
7. Check all nuts & bolts for correct torque.
8. Check for power steering fluid for proper level.
9. Wheel bearing/hub units (though they usually make noise at lower speeds and you probably would have noticed it if they were causing the problem).
10. Wheel alignment, both fronts & rears.
11. Worn engine mount(s), especially the one by the crank pulley, on passenger-side.

Also, wait till others reply to you, some people on this forum, especially on 850, are extremely knowledgeable, "Moderator Tech" being the top.

Cheers,


JPN

 

Try swapping the front and rear tires and see if it acts any different.
Tires can get hot and be out of round. But fine when cool.

 

The tryes (all four) and wheels (all four) have been replaced twice over the past four years in an effort to isolate the problem. One set of tyres was even replaced by the supplier on the assumption they were faulty. This seemed to rectify the issue for a short time but the shudder has returned threatening to render the car undrivable above 80km/h. The Volvo workshop state that they have checked all the suspension and bearing and engine mounts. In fact they are mystified by the issue and kept the car for a number of days to conduct some tests. I will take in the list of possibilities and get them to check them off. However, would I be better to take the vehicle to a thrid party suspension technician? Hamish

 

Maybe
Are you taking it to a Volvo specialists?
Or to a Volvo Dealer?

 

All the work has been done by the authorised Volvo workshop at the local dealership. The tyre work has been done by a leading Australian trye service company.

 

Hello again Hamish,

I apologize if my reply sounded annoying, I know it is not pleasant to get opinions which you're sure that you checked. I now understand that wheels & tyres are out of the question. If I make you annoyed further, please accept my apology that English is my second language and am only trying to assist you in solving the problem.

Also, please note that most people on this forum, especially on 850, are conscientious and they really try to help others, as it'll help even more people and in my case it is educational as well.

Anyway, I wonder if you could provide us with a bit more info on the shudder. I personally would like to know the following,when shuddering occurs.

1. Condition of the road, even when you drive on smooth highway,there may belittle irregularitiesthat you cannot see. I doubt this is a problem, but I just want to eliminate every possibility.
2. Engine RPM.
3. Ambient temperature.
4. Condition of the serpentine accessory belt (Any glazing on the belt surface, and when was the last time it was replaced? Is the belt of OEM Continental or 3rd party?).
5. Any loose exterior trim around the front-end (lights, bumper, splash shield, wheel-well liners, bonnet striker, etc...)

I'll also list things that I did not mention on the last reply:
1. Faulty ABS unit, deciding to open the valve to one of the front wheels.
2. Drive shafts out of balance (sometimes, though not often, road debris get on the drive shaft), or the passenger-side drive shaft bearing mount is loose.
3. Worn cv-joint, inner or outer. Usually noted by torn boots.
4. Loose steering wheel adjustment (tilt & telescopic functions).

If none of the above plus last replies from Tech & I seem to have a clue, the rack & pinion unit or the linkage between the steering wheel & R&P unitmay be at fault.


Also, try the following on an open road when there is no other car/object near you:
1. Let go of the steering wheel and see what happens. Try accelerating/decelerating with hands off the steering. Also, while you do this, try shifting the tranny between "D" and "3" (2~5 on manual) to see if something happens. Have your left hand by the steering wheel in case if you have to maneuver.
2. Brake moderately at about 100km/h.
3. Brake hard (notso hard that you go projectile) at about 100km/h.
4. Brake moderately at about 50km/h.
5. Brake hard at about 50km/h.

These may not sound effective solutions, but may reveal something that no one guessed. Every bit of try helps narrow down the problem in a situation like this, I believe.

As for visiting a 3rd party shp, I am not sure how they are in Australia. In case of the U.S., I avoid them when servicing imported cars. Is there another Volvo dealer or shops that specialize in Swedish/European cars within drivable distance?

I'll wait for your further reply,


JPN

 

Hi JPN,
No worries. I am amazed at the level of expertise on the forum. I only wish I could have found it years ago! In regards to your questions see below:

1. Condition of the road: A) seems to make no difference regardless of whether it is a Freeway or backroad.
2. Engine RPM.A) Usually around the 2500RPM mark
3. Ambient temperature. A) variable, would seem not to be a factor. Happens whether it be cold, warm or hot (we get the lot!)
4. Condition of the serpentine accessory belt (Any glazing on the belt surface, and when was the last time it was replaced? Is the belt of OEM Continental or 3rd party?). A) It would have been checked and replaced in accordance with the scheduled Volvo service. However, I will have it checked again.
5. Any loose exterior trim around the front-end (lights, bumper, splash shield, wheel-well liners, bonnet striker, etc...) A) All boits attached. I thought this as well right at the start of the problem and eliminated it from the equation early.

I will have all of the below matters checked at thge next service which is in a couple of weeks. Simple problems would seem to occasionally have big symtoms!
1. Faulty ABS unit, deciding to open the valve to one of the front wheels.
2. Drive shafts out of balance (sometimes, though not often, road debris get on the drive shaft), or the passenger-side drive shaft bearing mount is loose.
3. Worn cv-joint, inner or outer. Usually noted by torn boots.
4. Loose steering wheel adjustment (tilt & telescopic functions).

Rack & pinion unit or the linkage between the steering wheel & R&P unitmay be at fault.

I appreciate all the help you guys are providing. Lets hope we can solve the problem!
Hamish

 

Do you notice and back pressure when trying to turn?
Like when you turn do you feel the steering wheel fighting you harder than normal?
That is a very common sign of a bad steering rack.

 

Hi Tech,
No back pressure when turning. Car actually drives well under all circumstances. Doesn't pull or favour in steering.
Hamish

 

Ok that is a good thing then.
Did the tire place to a Dynamic Balance on the tires?
That also measures the tires for even a slight bit of out of round.

There isn't many common things on the 850's that will cause a vibration.

 

Hello ,
I am new to this forum so please bear with me.I am in the middle of changing my rear main seal on my 96 GL, but I have the same problem so i thought I would fix it while I have the engine out. Mine shudders @ 70 mph. I have put it down to the drivers side rack bushing.The one inside the rack. I can see it move from side to side in the bore when I actuate the steering. I was wondering at the same time if anyone knows a way to re shim this problem.I would hate to buy a new rack. Maybe this is your problem as well. It does have a lot of movement, when I think it should be in there snug.

 

Are the tie rods in good shape?
Are the balljoints in good shape?