Tranny Fluid on a 03WRX 4eat, no mods, 100k miles and no tranny issues, original fluid 05 LGT 5eat, "stage 2" mods, 118k miles and no tranny issues, original fluid Why not: 04 Escalade ESV 125k miles and no tranny issues, original fluid I plan on changing tranny fluid filters on all and thus the question regarding fluid extraction/replacement
I generally feel a drain-and-fill is much better (I typically do one, drive it for a week or so, and then do another w/filter, as you only get about 1/3 of the fluid changed each time). Disconnecting cooler lines to connect a flushing machine can cause issues. Also, either way, be sure to check the fluid level several time after the fact. It can take a few cycles to get all the air out.
Drain and fill. Flushes are generally a waste of time/fluids and can potentially harm something by knocking debris off. Several Manufacturers have spefically mentioned to not do it (Honda is the only one off the top of my head that I can remember right now).
I feel like I've never heard that using an outside source to "flush" the fluid is ever a good idea. When I used to have a Crown Vic, "everybody" suggested to pop one of the lines off at the cooler, then start the motor and let it pump itself out. You ended up getting a lot more fluid out of it than just draining/dropping the pan. Also, when you went to drop the pan it didn't dump all over a player. Not sure if this would be a yay or nay on a Subie or not. More importantly. Rick. What the hell's with all the auto sports cars?!
Its so much easier...In our previous 03 wrx we had a 2800 rpm level ten stall converter. My Lord was that thing quick off the line!
Finally getting around to doing this. I'm going to drain the fluid on our 05 Legacy GT and our 03WRX. Both are automatics. Best guess on how much Subaru ATF I will need to buy to refill each vehicle?
Bumping this up. I have a 2006 N/A Impreza. The owner's manual specifies the HP ATF fluid. Any issues using something like Valvoline Max Life synthetic ATF instead of the OEM? Edit: May have answered my own question. Product sheet at link below states specifically that it can be used for such applications. https://www.valvoline.com/our-products/automatic-transmission-products/maxlife-multi-vehicle-atf
Not in the USA at least as far as I am aware (there are a few auto STi's with 5 speed autos-- https://jalopnik.com/5600541/yep-thats-a-factory-built-subaru-sti-automatic). How much do you save using the Valvoline? Last time I looked, the name brand ATFs weren't much different from Subaru HP-ATF. I only own autos that call for the regular Subaru ATF (or Dexron III), so I've never bought the HP-ATF.
Price of the fluid isn't that different but it is certainly more convenient since I can pick it up at the local parts store or Walmart. Since I posted the question above, I've read on several forums, including bitog, that the Valvoline is good fluid and the 4eat of any year remains happy on it. People sure have strong opinions about automotive fluids. People had more to say about the filter. Apparently there is no actual substitute for the OEM as it's a unique structure compared to the aftermarkets from Wix, etc. Though people have had long term success with the Wix as well. More importantly, I found no horror stories about catastrophic failure, or even poor shifting results with the Valvoline fluid.
Flush machines typically work like a IV and do not do anything but allow fluid to flow out and new fluid to flow into the cooler as it would normally. Doesn't put any abnormal pressure or "flushing" and better described as a "fluid exchange". Typically why the fluid exchanges hurt stuff is vehicles with a filter that is plugging up and new fluid is thicker then thin worn, almost like water, old fluid. This thicker fluid going through a clogged filter causes issues from my experience. I'm no trans expert but this has always been my experience. I've "flushed" over 1000 transmissions in my career prior and every single one we changed the filter when applicable, and none of those failed unless they were already slipping, kicking, or bad in some way... even the very severe ones. But again I am no expert on auto trans internals and this is just my experience.
Also, valvoline maxlife atf IS amazing fluid and highly tested. On another note, Honda oem fluid tested in the bottom 10% out if 50 different fluids... so if you own a Honda get that fluid out of it. Lol
