96 850 GLT Wagon rear vibration

Hello All

I own a 96 850 GLT Wagon 160,000 miles and going strong!

My issue is that I have this odd vibration that comes and goes at
about 70 mph. The best way to describe it is a slow pulsing
vibration. It seems to be coming from the rear passenger side. I've
had the tires double checked and they are perfectly balanced, my
mechanic replaced the shocks as one was bad, but it still vibrates.
I've had my mechanic check it over several times but he can find
nothing.

One clue - if the vehicle is loaded with luggage etc the vibration is
barely noticeable it is much worse when the vehicle is empty.

Could this be a suspension issue? Do I have a bad tire? Maybe a bad
bearing? Could it be a rubber bushing is missing?

Thanks in advance for your thoughts.

Regards
Russ

 

Going out on a limb here -- a "slow pulsing" sounds like a harmonic
imbalance. You might try moving the rear tires to the front and
vice-versa. Might cure the problem and might move the problem to the
front in which case it's a tire issue -- possibly a tire balance issue
since it sounds to be speed specific.

I would try this first.

Oh, yeah, you could also try observing the speed limit and the problem
wouldn't occur. <G> But what's the fun in that, right?

Chuck Fiedler
Nothing but Volvo since 1974

 

How do you know he's not? There's a number of areas around here where the
speed limit is 70 mph, and some states are higher than that.

 

Chuck

Thanks for your reply I will try swapping the tires around and see
what happens.

As for the speed limit, Yes in Florida the highway speed limit is 70
mph. That's what makes this so annoying. I have to go faster that
the speed limit to make it stop, which risks a speeding ticket or go
slow and upset the other drivers.

Anyway, Thanks for the reply.

Regards
Russ

 

How many miles on the tires and do they show unusual wear patterns.

 

Lighten up.

 

Actually, that rather confirms my suspicion -- a speed-specific
vibration tends to be a tire/tire balance issue. Right now you need to
isolate the cause and swapping the tires around should do so.

Chuck Fiedler
Nothing but Volvo since 1974

 

Russ

If your tyres as still good get your local tyre blokes to re-set and
re-balance the tyres on the wheels.

ttfn.......Alistair

 

Hello All

I went tried all the suggestions here in the group and the problems
did not go away. So I finally took the car to the tire store where I
bought the tires. Long story short - I had THREE bad tires that would
not balance on a force balance machine.

Under the warranty conditions I got 75% of the value of the three bad
tires applied to the replacements. I ended up buying a fourth one
just because I didn't trust the last one.

I talked with the tire guy and he said it is uncommon and surprising
that I got three bad tires but I am really shocked. This is not a
statistical anomaly. I could see one or maybe two but not three.

What are your thoughts?

Regards
Russ

 

What band of tires?

 

They were Cooper tires.