Does it matter which way the ATF flows through the stock Subaru cooler (the one that's integral to the main coolant radiator)? I'm taking off my aftermarket cooler (not towing heavy any more), and don't want to blow coolant everywhere just to find out which line is supply and which is return. Does it even make any difference? I wouldn't think so, but I'm sure some of you will know better than I. Thanks.

Just flushed a 93 Legacy, in the top and out the bottom.

 

The hard line bolted along the frame rail that points straight up is the top hose-the feed line. The other is the return.

Hmm... Well, the Baja (what I have), like the newer Legacys, doesn't have a 'top' and 'bottom.' Both ATF lines are in the bottom radiator tank, and there's a left and right. The hard lines along the frame rail from the tranny are also both pointing nearly-straight down. There's a forward one and a rear one.

 

??

Hmm... Well, the Baja (what I have), like the newer Legacys, doesn't have a 'top' and 'bottom.' Both ATF lines are in the bottom radiator tank, and there's a left and right. The hard lines along the frame rail from the tranny are also both pointing nearly-straight down. There's a forward one and a rear one.

 

??

 

 

Its not a cross flow radiator?

 

It doesnt matter when your removing your external cooler, but it does when you add it. You want to cool the fluid before it goes in the radiator, as it also helps to heat up the tranny fluid. Putting it in after the radiator can cause the tranny to take longer to warm up.

 

nipper

Yeah, I was trying to explain that to the shop who originally installed it for me, but they flatly refused to plumb it that way. They were just stuck on how that would put heat back in the fluid, which was almost worse than heresy to them.

 

Anyway, if the flow direction doesn't matter, then I'll just un-hook and re-hook. I'm not going to use them both, just the factory one. Don't need the aftermarket any more.

 

My ATF cooler (stock one) is a cross-flow, though I must not have phrased myself very well. I meant to say that the factory input and output are on opposite sides of the lower tank on the coolant radiator. So, the ATF inside flows across the tank, just as you say. Sorry if I was unclear before, and thanks for the help.