Help with a driveline diagnosis

[libertyordeath]

Hi everyone,

 

Just a quick update. I was on the cusp of ordering new front CV joints, but opted to get new tyres first. Put the new ones on the front and rotated the fronts to the rear (about 80% tread).

 

Driving out of the tyre store, problem appears to be resolved! I don't think it was anything to do with wheels being out of balance etc, but for some reason the car pulls smoothly from low speeds and the weird throbbing seems to have gone.

 

I notice if I really accelerate hard from a standing start, basically like a race start only, there is a slight vibration like before. I suspect the front CVs as I am running out of options that haven't been replaced.....

 

One final note is that I have been running the tyres at around 40psi. I notice that the tyre store has filled the new tyres to 36. It is the only discernable difference that I can make other than the new rubber.

 

Thanks to all for your comments and help - for now it looks like this case has been put on ice (I am not going to say closed!)

[silverton]

40 is a bit high, you're going to wear your the center tread faster than the outer treads. I'd recommend Subaru's spec on the door, if you have OE wheels that is.

[dgoodhue]

Hi everyone,

 

Just a quick update. I was on the cusp of ordering new front CV joints, but opted to get new tyres first. Put the new ones on the front and rotated the fronts to the rear (about 80% tread)

 

You still need 2 more tires. 80% tread vs 100% is still too much of difference for an AWD vehicle. I am glad it helped but it is still going ruin your AWD. The spec is a little over 1/32nd difference (1.3/32) 2/32nd might be alright.

 

As I said before if you want to take the pressure off your AWD with the front set of tires and rear set of tires spinning difference speeds, put 1 new tire on on the front, 1 new tire on the rear.