99subrew Posted August 8, 2006 Share Posted August 8, 2006 should i mount 1 of those rv trans coolers....i was thinking the bigger the better ...plus this would mean more cool trans fluid flowing through the system. what yall think? Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted August 8, 2006 Share Posted August 8, 2006 Sounds like a plan! If you do any kind of hill driving, towing, hauling lots of people and/or cars, hot weather driving, I'd put in a big boy. Otherwise a smaller one might be adequate. This will of course somewhat reduce airflow over the A/C coil and radiator, but I haven't had any problems with that. I'd also spring for an ATF temp gauge on the AT outlet to cooler else you don't know how hot the fluid is. I like the aftermarket cooler in series after the radiator in-tank cooler and shoot to keep the ATF exit temp from the AT at no more than 180 deg. F. I've got a medium size PermaCool 1-1/2" thick, 10"x14" I think it is on the '00OBW, and I haven't seen temp climb above about 150 deg. F. yet on a hot day. The '96 Legacy has a smaller PermaCool, I think it's 1-1/2" thick by 7"x14" and it will get to 180 deg. F. on a 90 deg. F. day in stop and go or hilly driving; highest it ever got was 210 deg. F. climbing long steep hills in 1st gear. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 10, 2006 Author Share Posted August 10, 2006 thanks for the info on your coolers. i think i will go for the big 1.... the temp gauge is going on for sure! Quote Link to comment Share on other sites More sharing options...
nipper Posted August 10, 2006 Share Posted August 10, 2006 thanks for the info on your coolers. i think i will go for the big 1.... the temp gauge is going on for sure! where you mounting the gauge sensor? nipper Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 10, 2006 Share Posted August 10, 2006 in this case, the "bigger is better" philosophy is incorrect. the automatic transmission is designed to run with fluid at a certain operating termperature. the goal isn't to make the fluid run at the coolest temperature possible. the goal is to make sure the fluid never exceeds damaging temperatures due to non-nominal instances that may increase the ATF beyond normal temperatures. these may include but aren't limited to.....degraded ATF cooling systems (usually old radiators), an overheating engine (which overheats the radiator and ATF if still equipped), or hard driving like towing, hills, climbing, frequenty shifting and offroading...etc. Subaru's are small light duty vehicles. Unless you're towing something large up mountains on a frequent basis you won't need a large cooler, the smallest will due just fine. have a look at the stock set up...even the smallest aftermarket cooler is many times more efficient. and yet people drive automatic transmissions to 200,000 miles with the stock set up. a bigger one will be more a PITA to install anyway. i'm not one to say a larger cooler will cause issues, but i'd stick to keeping it close to the stock design on this one. Quote Link to comment Share on other sites More sharing options...
benebob Posted August 10, 2006 Share Posted August 10, 2006 Don't put one on until you put a gauge in and see where its running at! Proper temp is 140-170 in most driving conditions but 190ish is fine when its 100 outside. Lower than 130 isn't real good on the tranny just as 200 isn't. Bigger isn't necessarily better, esp. when winter comes. Don't block off the radiatory cooler either as it also acts as a fluid warmer from a cold start. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 10, 2006 Author Share Posted August 10, 2006 so medium to small would be best ? i deliver mail so my tranny shifts all the time and i creep olang at slow speeds for long periods of time, but i don't have any idea what temperature my fluid is reaching. i guess i need to install a atf gauge asap so i can see some numbers..... this will be interesting, i will order one, install, then let you guys know what temps it's hitting..... Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 11, 2006 Author Share Posted August 11, 2006 order is done....summit analog gauge with inline block to link up to. Quote Link to comment Share on other sites More sharing options...
nipper Posted August 11, 2006 Share Posted August 11, 2006 order is done....summit analog gauge with inline block to link up to. got a link? mipper Quote Link to comment Share on other sites More sharing options...
benebob Posted August 11, 2006 Share Posted August 11, 2006 I have the Norsdouq from Summit. The best place to put it is in the pan. Anywhere else you're not getting as accurate of results Quote Link to comment Share on other sites More sharing options...
idosubaru Posted August 11, 2006 Share Posted August 11, 2006 so medium to small would be best ? i deliver mail so my tranny shifts all the time and i creep olang at slow speeds for long periods of time, small would be fine for your circumstances. benebob, which vehicle has the ATF temp sensor installed? what kind of reading do you get? does it vary much...season, ambient T's, hills, highway? there's a post on USMB somewhere of a guy that used one of those laser temperature devices to see the temps before and after installing the cooler. made for interesting reading. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted August 11, 2006 Share Posted August 11, 2006 I put in this auto meter in the AT outlet to cooler line. I figure that AT outlet to cooler is the hottest temperature point I can measure. With a switch and an extra sensor in the pan you could monitor both temps. Sometimes in the winter I put a piece of Reflectix insulation infront of the ATF cooler so the temp has a chance to get above 100 deg. F. at least. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 11, 2006 Author Share Posted August 11, 2006 thats the one i ordered from Summit! thanks for the link, i cant wait to bolt it up and see temps....i think im reaching 230- 230 at times but its only a guess. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 11, 2006 Author Share Posted August 11, 2006 boo boo ....210-230 lol Quote Link to comment Share on other sites More sharing options...
benebob Posted August 11, 2006 Share Posted August 11, 2006 boo boo ....210-230 lol If you are you fried your tranny long ago. The flash point (when fluid breaks down immediately) for Mobil sythetic (which is the highest independenty verified temp ATF out there as Redline and Purple won't let 'em test theirs) is 212 degrees. On my SVX with spirited driving and sitting in traffic at 100 degrees outside (with a 19000gvw cooler) I've never exceeded 210 on the digital gauge and a pan sender. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted August 11, 2006 Share Posted August 11, 2006 There are other syn ATF's with a flash point above 212 deg. C. I would say temps of 210-230 deg. F. in normal summer driving could easily be reached with the stock cooler. I ran Mobil Syn ATF for a while; seemd like a really nice fluid. Mobil's Web site shows a flash point for their syn ATF of 236 deg. C. I hope your gauge temp of 210 deg. is deg. F, else you could flash fry a Buffalo in that fluid RedLine publishes in their spec sheet for their 'high temp ATF' a flash point of 238 deg. C. I think pan temps can be misleading because this fluid is already cooled and is probably the coolest point in the system. Flash point indicates the temperature at which a specimen vapors will ignite. Flash point assesses the overall hazard of a material and is used in shipping and safety regulations to define "flammable" and "combustible" materials. Quote Link to comment Share on other sites More sharing options...
benebob Posted August 12, 2006 Share Posted August 12, 2006 There are other syn ATF's with a flash point above 212 deg. C. I would say temps of 210-230 deg. F. in normal summer driving could easily be reached with the stock cooler. I ran Mobil Syn ATF for a while; seemd like a really nice fluid. Mobil's Web site shows a flash point for their syn ATF of 236 deg. C. I hope your gauge temp of 210 deg. is deg. F, else you could flash fry a Buffalo in that fluid RedLine publishes in their spec sheet for their 'high temp ATF' a flash point of 238 deg. C. I think pan temps can be misleading because this fluid is already cooled and is probably the coolest point in the system. Flash point indicates the temperature at which a specimen vapors will ignite. Flash point assesses the overall hazard of a material and is used in shipping and safety regulations to define "flammable" and "combustible" materials. I said independently verified. You can post whatever you want on your own site but until a lab with no ties to your company verifies those results how accurate is that? You're thinking on the pan would be wrong for whatever reason. Mine was tested with a sender near the radiator and with one in the pan. Sender is plenty far away from the return line in the pan as you'd probably be right if it was near to it. Guess which one was between 10-25 higher? Ah but remember what also happens at that flash point! The higher the better as at that point the molecular structure breaks down. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 15, 2006 Author Share Posted August 15, 2006 sense i'm putting mine inline, i suppose it should go on the hose exiting the tranny? this is were i was going to mont it so i could see what the temp is b4 cooled....? Quote Link to comment Share on other sites More sharing options...
benebob Posted August 15, 2006 Share Posted August 15, 2006 sense i'm putting mine inline, i suppose it should go on the hose exiting the tranny? this is were i was going to mont it so i could see what the temp is b4 cooled....? Like was previously stated do a search. I'm not gonna get into where it should go and why aside from saying in the PAN is by far the best. Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 16, 2006 Author Share Posted August 16, 2006 it does seem like the temp readings you would get from the pan would be altered with cool fliud returning into the system. were do most drag cars, race cars etc. put theirs? Quote Link to comment Share on other sites More sharing options...
benebob Posted August 16, 2006 Share Posted August 16, 2006 it does seem like the temp readings you would get from the pan would be altered with cool fliud returning into the system. were do most drag cars, race cars etc. put theirs? DO A SEARCH. I OUTLINED THE STUFF IN A POST ELSEWHERE NOT A MONTH AGO! YOU WOULD BE WRONG THOUGH! Quote Link to comment Share on other sites More sharing options...
99subrew Posted August 16, 2006 Author Share Posted August 16, 2006 BONEBOB, i did a search it was helpfull, thanks Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.