Legacy 3.0R bad steering vibration

[Hadrienlf]

Hello all,

 

New Legacy 3.0R estate owner here. I own quite a few cars ( nsx, integra, delta evo1, 850R, ... ) and bought this for cheap for my GF but what happened is that I actually use it all the time because I discovered how such a good car it is.

 

The car has 130.000km, drive very well except for a bad steering wheel vibration.

Symptom : The vibration itself is the steering wheel going left to right by a very small amount but enough to shake my whole arm.

 

- The car had an alignement and new front tyres before i bought it.

 

I brought it to a mechanic, who apparently re-balanced tyres.

Vibration is still here but a bit less.

 

- Steering wheel vibrate from 110 to 140km/h not below and not above.

- Vibration stops sometimes when I take long corners at those speed and then appear again when the road straightens.

- Vibration reduces sometimes 80% on some road surfaces ( highway here in France are some of the best in the world and the brand new surfaces seams to reduce even more the vibration )

- The car is going to the right at highway speed above 100kmh, below it goes straight.

- Rear tyres are Michelin that are 70% and that are 10yo. Fronts are new.

- I now have brake vibration when i brake hard at highway speeds. Can be felt through the steering wheel mostly and only above 100km/h

 

I am not familiar at all with those Legacy so if anyone already had this, i would gladly take some advices.

 

Thanks a lot !

[Max Capacity]

Seems to be a common issue lately.

You sound like you might have brake pad dust build up on the rotors. Try re-bedding the brakes. You can google it and find out how.

 

Basically, do 5 or 6 almost stops from about 50mph. You need to get the rotors really hot to clean them. You should be able to smell the brakes. You may even see dust in the rear view mirror.

[Hadrienlf]

So i tried that and it changed only at very low speed something.

Before i could sometimes hear maybe a pad/disk friction noise after releasing the brakes but just a few seconds. Now this is totally gone.

 

But the brakes from above 100km/h shacking is still here, and the steering well vibration at high speed too.

 

I am leaning towards warped disks or an unbalanced wheel but not sure at all.

[Max Capacity]

Swap the wheels, front to back, and see if the issue goes away, or if you can now feel it in the drivers seat.

 

You may have a bent wheel ?

[lagwagon]

Circumferential spec on tires is all within 1/4” (6mm). Two tires at 70% and two new will almost certainly be out of spec. It might not be causing the vibration (check suspension bushings) but it will eventually cause problems with the differentials (a/t and m/t) and/or center clutch (a/t).

[Hadrienlf]

Hum, yeah there is quite some difference between the front and rear tyres.

I will try swapping that around.

 

I brought the car to a mechanic and he re-balanced the wheels. No difference whatsoever happened. He told me he was suspicious about my rear left wheel being bent.

 

Weird cause if it was a rear wheel bent then i would have seat vibration and not steering wheel vibration.

 

Another factor, yesterday i was smelling burnt rubber and there was some very light clear smoke coming from the engine. After some looking everywhere i noticed that the inner front left shaft ( gearbox side ) grease had being thrown on the exhaust heat shield. ( Did 2000miles in 8 days with the car ).