1 Lucky Texan

^^^good post, second the oil minor point but, easy for folks to overlook the cabin air filter.

if it's like a squeal, could be the backing plate has trapped some debris against the rotor, or is dragging?

welcome back Dusty, there are folks here with ej22 swap experience. Someone will reply I'm sure - the recent virus issue may have some folks a bit distracted. try a search to read about swaps.

4 cyl or 6?

WANT!!!

some older filters had bad crimps and would leak sometimes......r

looks like hubs were done

could an observer in another car 'pacing' you perhaps see something? video the front corners, etc.

is it less noticeable on wet roads by any chance? or on gravel?

I edited my last post, el freddo is talking about center drive shaft I think?

EDITED; have half-shaft/CV axle nuts been torqued with wheels on the ground? FSM says not to do that - no weight on the wheels.

as a triple check, find the tooth count for your engine.

check hub/rotor/caliper temps with an infrared thermometer after a highway run. is the wobble in sync with tire roation - or, 'about' 4 times faster? if you lightly touch the brakes while wobbling, can you feel pulses in the brake pedal or, does it change the symptom? did this begine gradually or after some work on the car?

Pretty sure my 06 WRX wagon got a faster ratio vs 05. Maybe the 05 Saabaru was ahead of the curve?????

ah, I guess that's right. I thought it was only VDC.

does it idle rough? if so, try a stream of propane from a handheld torch or some ether-start into the intake. If idle smooths-out, that may point to a fueling issue. check all grounds.

one thing for certain, you must use the FWD fuse in the block under the hood if you mix tire sizes. Even very slight differences are very stressful on the drive train and it's usually the trans that suffers. so, use of the donut requires use of the FWD fuse. seriously. tires need to be the same size/brand/model and near each other in wear. that trans also needs OEM or compatible fluid. of course, check fluid level when idling.

is there oil on the plugs or their boots?

hmmmmm....did this same shop do the brake work that preceded the rattling problem? kinda wondering if some 'accident' is being 'covered-up' -like the car shifted/dropped on the lift or ????? if we think a welded nut or other steel object is causing the noise, maybe a very strong magnet in some various areas near the rear support for the lwr ctrl arm's rear bushing - might 'trap' something loose?

hows the anti-rattle hardware? supposed to keep pads from rattling.

quite possible incorrect alternators from parts store.

try pb blaster, then tighten a little, then loosen....

any chance there's a CD stuck in the radio? that has caused problems on some cars before. stuck in some EJECT cycle.

the NA (non-turbo) Imprezas will not have the asymmetric 'rumble' like the turbo models - unless an unequal length header is installed. I don't really understand the OP's question - has the original exhaust system rusted away? anyway - it is possible to interfere with proper pressure pulse 'propagation' if the exhaust piping is of mixed diameters. But, many folks fit partial or entirely new complete exhaust systems without drama. I wouldn't expect noticeable power increase.

unlikely the rotors will help much IMHO - fresh fluid is important as old brake fluid has a reduced boiling point due to moisture. many people like EBC. I run Stoptech Street Performance (they have a different name now?) and they are good value for an upgraded pad. Long-lasting, noise free, great 'cold bite', good modulation, etc. Higher MOT than Hawk.