Only after driving 20-30 minutes on the highway out of nowhere the front of the car will start shaking significantly. Still happening in neutral while coasting at speed and during shake pushing the gas pedal seems to cause little to no speeding up. Don't think it is in steering wheel and is more in engine I think. Enough shaking to make me pull over and shut down.

 

And then when I start back up and get up to speed it seems to be ok again. Talked with local dealer and he thinks it could be bad wheel bearings given it needs to warm up before being an issue. Any thoughts anyone?

 

2009 Subaru Legacy, non turbo, 101k miles, already replaced CV coupling and some other maintenance.

 

Thanks

Josh

 

 

If the CV was replaced with aftermarket CV axle then that is a possible suspect.  Aftermarket CV axles are plagued with issues, very common.

Did this issue exist before the CV replacement?

Did this issue appear after the CV replacement?

 

Any check engine or dash board lights?

Does braking change/affect it?

Does steering change/affect it? (going straight or turning)

tell us more about the car's history? is it a 5 spd? (they sometimes have torque bind that is worse after warming-up)

 

tires all the same?

 

ever have a trans or rear diff swap?

 

u-joints and carrier bearing OK on drive shaft?

if it happens in neutral - wouldn't that essentially rule out the engine?

 

alignment?

Not sure about what the dealership used for CV. Issue is now coming up 1-2 years after the repaired happened. Before it was an issue of slow tight turns causing binding and slipping, for example when pulling into parking spots.

 

No check engine lights, brakes or turning doesn't appear to change anything. Just happens as I am driving along the highway and pops up randomly as I am cruising along after about 30 minutes. Just driving along a pretty flat straight highway, nothing out of the ordinary. Tires are only a year or two old and have some inconsistent wear, but nothing too bad I don't think. Back during that repair I did just recently realize that they put one of the "directional" tires on the wrong way but not sure how much that hurts things.

 

 

If the CV was replaced with aftermarket CV axle then that is a possible suspect.  Aftermarket CV axles are plagued with issues, very common.

Did this issue exist before the CV replacement?

Did this issue appear after the CV replacement?

 

Any check engine or dash board lights?

Does braking change/affect it?

Does steering change/affect it? (going straight or turning)

I think the key would have to be that it only happens after a good amount of highway driving and for some reason is fine once I let it rest for a minute or come back down to city speeds.

I would be skeptical its wheel bearings.

 

Have all the other front end components been checked?

I, too, suspect a bad CV joint. I had a car few years back that after driving hours on the interstate developed a bad case of the shakes. I barely limped it into a shop for repairs. Got a call next day from the shop, that they could not find anything wrong once the car and CV joint cooled down. Car drove normally. Got the car home, it acted up again, so had both half shafts CVs replaced, and problem was solved.

 

As reported, rebuilt half shaft CV joints are rebuilt as cheaply as possible, with the result that they don't last very long. Still a good idea to check out all front end suspension and steering components.

Could be a stuck brake caliper making the brakes drag on one wheel.

Drive it until the problem happens, pull over in a parking lot and hold your hand near the center of each wheel to see if any are significantly hotter than the others. An infrared thermometer is very helpful for this, but not necessary. If one of the brakes is dragging enough to cause this problem, the wheel that's dragging will be very obviously hotter.

Either a dragging brake issue or a CV is going/gone bad. My Loyale did this and my Legacy is currently doing this.

 

Both times, bad axle. (The Legacy is getting a new axle tomorrow)

 

Look for split boots, flung grease or even excessive play (up and down, not in and out. They can "shift" in and out a bit, normal)

is it a 5 spd?

 

They often have TB develop after warming up.

 

when the car is hot, do you still have jerking/binding in tight circles on dry pavement?

 

has the car ever had a trans or diff swap? You say the tires are fairly new, but, are they ALL 4 the SAME exact brand, size and model? has it been operated with mis-matched tires in the past?

Edited June 19, 201510 yr by 1 Lucky Texan