1 Lucky Texan

if you haven't been thru a tank yet, one of the floats may be stuck high giving false positive info that you are near 1/2 tank when you may be near empty.

ATF is near the firewall on the left (US driver's side) front diff is on the right side, somewhat lower and maybe a little further back some cars in that time period had a parking pawl recall(might rattle ??? I think, check www.cars101.com) , but I can't help think you should also inspect for a broken axle. that car needs a thorough inspection, new fluids and other TLC. check the 'stickies' at the top of the Gen 2 Forum too. are the tires all the same brand/size/model and near each other in wear? they need to be.

scan ECU for stored/pending codes might be fuel issue? weak pump or ?????

yep - It creates a documented way to maintain consistency so, if you make a bad product, it will stay bad, in the same manner, everytime it's produced!

P0420 code? there can be other reasons for it to be on than a bad catalytic conv. Even a simple exhaust leak. But, if your mechanic knows his stuff, cats can go bad and yours is fairly old. Just ask him if he feels certain this will get rid of the code, and what he's prepared to do for you if it doesn't. Or consider a second opinion, for $750 it may be worth paying for a second diagnosis if the problem is something simple like a vacuum or exhaust leak. If the car runs well and the cat isn't clogged, that codes is benign and, if TN doesn't emissions test a '99, you could just drive the car as-is.

are the trans and front diff fluids at correct levels now? The automatic trans level must be checked while idling on level ground. best if the engine is warmed-up and after moving the shifter thru each gear before stopping at Park or N with handbrake on. how many miles on the car? what is its general condition? has it been well maintained? new to you? are there any fluid leaks? any repairs done lately?

others here know more about the VDC, but pretty sure the trans fluid capacity, type, procedures are the same as 'regular' 4EAT. many folks like Valvoline MaxLife synth. , others like the Subaru ATF-HP (backwards compatible, mandatory starting in 05 I think))

Is the coolant nasty-looking? Any signs this car has been run with straight water and no antifreeze? I'd be suspicious of an internal head gasket leak and a possible wrong diagnosis about the trans fluid. But, if there's any doubt, one test could be to disconnect the lines to the cooler and temporarily connect them together. Run the car a little and watch for; A. leakage of coolant from the coil. B. overheating also, the thermostat MUST be OEM-style, with the larger wax capsule. Don't run the transmission too much if you feel there's coolant mixed in the fluid! while pricey and a little bit of a hassle, fluid samples could be sent to Polaris or Blackstone labs.

must check while idling, warm best. If it looked ovefilled by a lot with engine off, it may be dead on while idling. But a small amount over the appropriate mark while idling is probably not a problem. go slow when filling, the marks on the stick are are not a quart apart like engine oil, more like a pint. filling is easier with something like this;

confirm fluid level - wonder if it's possible radiator has leaked into the trans cooler coil and vice-versa? with above fluid change - try a bottle of Trans-X (CRC or K&W ?) or similar on the last fill?

go to the amazon reviews, look for the search reviews box and try putting in 'automatic' or 'auto' and see if a reviewer has actually used the part in an auto. this works well most of the time, but I admit, it may not for something with low sale or only a few reviews.

yeah, as it's hygroscopic, the fluid's boiling point becomes reduced. there may be other additives that help keep seals happy. OEM pads are great, akebono ceramic, but, many people save a little money and have no issues with name-brand aftermarket ceramic or maybe semi-metallic. I like the Centric PosiQuiet Ceramic. long-lasting, noise free,similar dust and performance to stock pads, good value. On my WRX that gets a little spirited driving, I run StopTech Street Performance. they are also good for the occasional track day. Good initial bite cold, modulate well, not crazy $$$ - but dusty!

Sill Impreza-based, but did get bigger, then, bigger again in 2013? I think; from wiki;

you should also consider a Forester - opens-up a lot more used cars to you and is basically the same 'platform' as OBS, just taller body.

are you running good tires? what pads are you running? had the fluid flushed?

There may be some Chinese corps that do well. Supposedly, the ones that are ISO-9000 certified by European auditors are OK. But maybe not the ones certified by Chinese auditors.

I don't recall specifics, but the one I got at the local parts store worked fine for me.

first, try taking a temp reading after a cold start - confirm the reading is near the ambient temeprature - if not the engine temp sensor may be bad. If you're concerned about the piping causing high intake temps, consider insulating it with something. A wrapping or split some kind of foam tubing to place around it. etc.

I think there's a sticker under the hood with the capacity listed(22 - 24 ozs?) - two 12oz cans should be correct. Compressor may begin pulling after one can.

you could try the Subaru Coolant conditioner (it's repackaged Holdt's RadWeld leak stop) ONLY 1 bottle total ONLY installed per directions I have read several posts of people installing radiators for leaks or internal clogging, etc. Several in cars newer than '97 so, yeah, nothing special about soob radiators. Ebay seems to be a popular place for replacements, I suspect Amazon, RockAuto, Advance, NAPA and others could be fine too.

on the oil idea, maybe drip some on a heated nail and carefully take a small whiff - maybe it will smell like OILY, toasted marshmallows ?

hmmm....the car must be stopped? have you tried just turning the a/c system off-on ? there is a 'rev sensor' in the H6 comp. But try searching for that, I think the failure symptoms don't match your issue too well. some folks have replaced a/c relays for being 'weak'.... how much refrigerant did you put in the system?

kgol - Joe Spitz that runs www.cars101.com works at Carter Subaru (shoreline ?) maybe contact him to see what he would suggest? - http://www.cars101.com/subaru/contact.html

throttlebody 'MIGHT' be a possible - uh - 'intersection' ? of crankcase vapors and cooling system ?????????? I dunno, must be some car made in a different universe. seems crazy to me - I'd like to schedule a meeting with the mech or service writer to have him SHOW me this path of contamination. A leak from the trans cooler seems much more likely - check trans fluid level, you might consider sending coolant sample to Blackstone Labs or Polaris etc. and see if they can ID the oil or , hopefully not, find combustion products..

coupla Gates kits on Amazon have reviews mentioning - and showing - chinese parts. Afew dated in the JUne-July timeframe and one I saw as early as February of this year.