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has anyone ever put one on a impreza outback ? i do a lot of stop and go and i was thinking a trans cooler would help the fliud stay cooler under these conditions. my subaru has 75,000 and i want it to go another 125,000 if possible. if i put this on myself, how easy would this be to put on ?

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Most people don't know it, but an AT runs hottest at very slow speeds or when stopped. That's right, highway speeds genereally put very little thermal strain on an AT. Using synthetic AT fluid is very good advice. AT fluid actually runs hotter than engine oil! Even better than than an oil cooler, put your AT in neutral when stopped, especially in hot weather. Of course, you have to remeber to shift back into drive before your remove your foot from the brake.

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If you add a cooler for the transmission, install a temp guage for it also. If you're concerned about the tranny you might as well have an indication that you got your money's worth.

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Haven't put an ATF cooler on an Impreza Outback, but I have put them on both '96 Legacy and '00OBW. Pretty simple install if you're inclined. I figure bigger is better so I ordered medium size PermaCool heavy duty (1-1/2"thick) transmission coolers from Summit.

 

Basically, I found the hoses going to the radiator in-tank ATF cooler ('96 Legthey're on the LH side of the radiator; '00OBW they're on the bottom), then pulled one of them off. Convenient thing was they're just hose on a barb connections, no complicated manufacturer proprietary fittings there. Then I started the engine for a second to figure out which hose was the AT outlet (the one fluid came out of) and the return (the one fluid didn't come out of). (This is also a convenient way to flush the old fluid out of the torque converter when changing out ATF; draining pan only doesn't get it all). Then connected the PermaCool in series from the radiator in-tank cooler outlet and the AT return line with the supplied PermaCool hose which seemed the right size for the barbs.

 

The coolers are fastened between the bumper and front of the A/C coil jobby there in front of the radiator. Plenty of room there from what I remember. You could probably even fit an ATF cooler with integral fan if desired.

 

Also installed filtration in series with the ATF cooler circuit between the AT outlet and the radiator in-tank cooler. On these vehicles, there was tons of room inside the LH fender, just pulled that plastic thing out of the way under there. The screen filter in AT doesn't get the small stuff. Even the external filter on the phase II's doesn't filter like a bypass filter to get the maybe 2um stuff.

 

Preferably the ATF temp gauge would go near the AT outlet to let you know the fluid temp coming out (before cooling). Like to keep it below 180 deg. F, even climbing long steep hills in hot weather A/C maxed never gotten it above 210 deg. F with the cooler. After one day of climbing like this in the '96 it's slight torque bind in hard corners was gone. Suspect the cleaning action of good quality hot ATF melted off the junk on the clutches.

 

Synthetic ATF should be more resistant to undesirable oxidation. Currently running Amsoil universal syn ATF in both vehicles and the shifting is very nice; like it a bit better than Mobil1 syn ATF which I have also tried.

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thanks for the advise! this was alot of good advise, were was this mb when i had problems with my old 93 legacy awd (r.i.p.) i'm convenced i need a trans cooler, the synthetic idea and temp guage are nice ideas. i'll do that for sure! i never herd of a temp guage on a trans before, were can i get one ? since this is my mail car i'm never going very fast, maybe 1st and 2nd gear, the oil just stews in there until i can get to a point where 3rd and 4th hit. im getting one asap.

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Then I started the engine for a second to figure out which hose was the AT outlet (the one fluid came out of) and the return (the one fluid didn't come out of).

 

Did you install it so the fluid went through the radiator cooler first and then the aftermarket cooler, or the other way around?

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99subrew, you can get all manner of gauges from Summit Racing or Jegs. I like Auto Meter pro-comp analog; they seem good quality. Can get ATF gauge for maybe $40-50 including sender. They also have Cyberdyne digital if you go for a more ricey look. I don't like those junk overpriced sunpr like from Pepboys. I like Summit b/c anything I order by 6PM, I get the next business day. :headbang:

 

2X2KOB, I installed it so it goes through radiator in-tank cooler first, then aftermarket cooler.

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thanks , i'll check out auto meter gauges....it doesn't have to be nice for me just as long as it works good. thanks again 2 all

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Heat is a major enemy of neoprene seals and fries 'em into tasty bacon crisps. Synth fluid might be able to hold-up under high temps, but don't be fooled into thinking that the seals will come out unscathed.

 

Keeping the tranny fluid temp under control is key to extending the life of the trans. It's no small deal.

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