New front tyres - Transmission whine
 

Evening - just had new tyres put on the front of my 2005 Forester x which is at 100k well maintained.

After driving a few miles a whining noise appears in the transmission - starts at around 40 mph. If i knock the auto box into neutral it goes away. Wasn't happening yesterday with old tyres.

Anyone experienced this ?

Are the tyres definitely the same size? Also how worn are the rears?