Screeching timing belt countdown

Timing belts do not screech. How many miles on your timing belt?

Is the serpentine belt screeching? If an idler wheel on the timing belt has a bad bearing I suppose it might screech. In that case go ahead with the work.

FOR's correct again! The serpentine 5 rib outer belt driving the ps and alt on all 2000-2009 2.5i is subject to stretching and screeching after about 3-4 years use. Replacing this $15 belt takes 15 minutes, so just DO IT! While you're at it, have your wrench remove the left (driver's side) upper front plastic cover over the t-belt. You can then check the t-belt for cracks (common after 10 years) or oil contamination (rare); you can depress the top run with a finger or screwdriver to test tension too (it uses a shock-sprung auto-tensioner and a second idler pulley). Then restart the car and watch the t-belt go by at idle speed. It shouldn't hop around nor screech once the outer belt is replaced. BUT, if the above tests aren't passed replacing the t-belt and its tensioner and idler is indeed about $200 parts and 2.5-3 hrs labor. Ignore the water pump, as they NEVER fail! But the odds are 90% that the screech is the outer ps/alt belt; the remaining 10% chance is that its sister (4-rib) AC belt lower idler pulley is shot. The latter will elicit a constant scraping sound rather than an occasional screech. Replacing it requires removing the ps/alt belt anyway, so try to combine these simpler jobs. So the odds that the screeching is the t-belt approaches 0%. Find an indy wrench who's worked on Subarus often, not the generalist who wants $1k either naively or greedily.