Just read another thread about an issue with humming from the diffs on newage sti's
I noticed a humming noise especially decelerating on smooth tarmac - dealer said it was tyre noise due to stiff sidewalls on Potenza's

Thread said there was an internal memo from IM about the problem

Any info would be appreciated

 

my STi 05 also has a faint hum. I'm willing to bet money it's the sound of some part of the transmition. most likely the front diff, which is new w.r.t. the older ones. More stress-loading on the transmission calls for straighter-cut gears, which in turn tend to be singifficantly louder. In fact, if you take a ride in race-spec vehicles its quite likely that at high speeds the hum of the diffs will be the loudest noise in the cabin, even more so than the exhaust or induction!
The stock potenzas are also quite noisy. if you notice the hum decreases with varying tarmac you might find it's mostly down to tyres. If the noise is rougly the same irrespective of road surface, you're likely correct about the diffs. One thing is for certain, it's absolutely nothing to be allarmed about. I't s a sure-fire sign of pedigree and sturdyness, testament to motorsport background. I'm quite proud of it myself!

 

I've got a 2005 STi and I get a fair amount of tranny whine. From what I've heard it's pretty normal.

 

I've got a number of 2002 onward cars for sale and we've had a few through our hands over the years. They all seem to have a hum from the rear diff, some louder than others. With or without the Bridgestones on.

No need to worry unduly in my opinion. That and the smelly clutches they 'suffer' with as well. Incidentally I'm driving an EVo 8 [ Yeah, yeah - I know ]
at the moment and that has a smelly clutch too.

David APi Engines / APi Impreza [ APi Evo ]
www.apiengines,com

 

my sti 05 jdm has that transmission whine aswell goes away when start acelarating

 

I also get 'tranny whine' on MY03 2.0 WRX under engine breaking. Most noticable when hot (after a long motorway run).
-Steve.