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Criteria for a transmission cooler when towing

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We are moving next week and although we are having movers move the majority of stuff, there's going to be quite a bit of stuff we still have to move ourselves. we were thinking of renting a 4x8 u-haul trailer to put on the back of our 2000 forester (auto).

 

Do I need a transmission cooler? everything I've read RECOMENDS having one, but a lot of times people plan to tow multiple times. this is a one time deal and we are going 550 relatively flat miles (over 2 days- missouri to minnesota). the trailer apparently weighs 600ish lbs empty and we'll ahve 2 adults, 2 kids, 4 cats in the car with maybe a few hundred lbs in the trailer.

 

I'd like to install a cooler, but I'm so pressed for time now. If I can get away with not putting in a cooler, that would make for 1 less thing to worry about. otherwise, if I run a risk of damage, I'll certainly make the time.

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5MT or AT? If it's an AT, I would STRONGLY suggest getting a cooler. If it's not, I still suggest getting a cooler. You're going to load that thing down and add weight that it has to pull - not good for the transmission.

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I think you're fine. That size trailer is ok as long as you use some common sense down the interstate.

 

Easy acceleration

moderate cruise speeds (55-60mph)

downshift to 3rd on hills and slow down, AC off

easy decelleration (brake friendly)

 

 

rd

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I think you're fine. That size trailer is ok as long as you use some common sense down the interstate.

 

Easy acceleration

moderate cruise speeds (55-60mph)

downshift to 3rd on hills and slow down, AC off

easy decelleration (brake friendly)

 

What he said. I think your car should have an AT temp light, obviously, if that illuminates, heed its warning. You can overheat auto trans fluid pretty badly and so long as it is changed promptly afterwards, you probably won't cause any permanent damage to the trans. If you are concerned, have the ATF changed once you get to your destination.

 

Tow safely,

Nathan

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I'd go for the ATF cooler but if there isn't enough time I'd change the fluid after the tow. Yes the thing has a light for too high a temp but I don't know what temp that comes on at, could be 250 deg F up to 300 deg F and both of those are prettttyyy hot.

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Installing a transmission cooler was no harder than changing the engine oil on my 2000. The hardest part was putting the oil lines through gaps in the radiator. Overall 3/10 on difficulty, just for the lines.

 

I installed mine after the factory cooler lines.

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If you're putting a cooler in don't bother unless you put a gauge in too. Undercooled is just as bad as overheated. How far are you going? If it isn't that far and you're not going to be towing again in the near future I'd simply change my fluid after the move. Anything above 210 is very bad. The idiot light comes on at 280 or something insane like that. Your tranny is pretty much already gone at that point. Might just want to invest in a gauge and stop for a break if it gets above 200 but honestly on the highway you should be just fine. Its stop and go traffic that will heat it up quick.

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agree with benebob. highly unlikely you'll reach high temps like he said for just some highway cruising and not many mountain climbs. if you're driving up many hills, don't let the transmission search, in other words shift multiple times up and down while climbing a hill because of the load. just take it easy and you'll be fine.

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The Forester has a 1000 pound limit for towing a trailer without brakes. I would be much more concerned with the braking limit than the amount of weight towed. I believe the same Forester has been given a 2000 kg towing limit in Europe.

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thanks for the replies everyone.

 

I think i will try to go w/o the atf cooler and change the fluid after the trip. Since the trip is 99% major highway and we will be traveling with small kids (ie many breaks), I'm hoping things will be ok. also the weather will be cool so I wont need the a/c.

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If you find yourself at a stoplight now and then put the shifter in nuetral. Unloads the tranny. Helps cooling of the ATF.

 

rd

 

Actually that increases temps for whatever reason or at least it does on my SVX with a digital gauge.

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The Forester has a 1000 pound limit for towing a trailer without brakes. I would be much more concerned with the braking limit than the amount of weight towed. I believe the same Forester has been given a 2000 kg towing limit in Europe.

 

1,000 lb limit in US vs 4,400 lb (2,000 kg) in Europe?

 

Methinks there's a conversion error someplace. :rolleyes:

 

That said, when it downshifts on a hill, put it in 3rd so it doesn't 'hunt' (as previously advised). As a matter of fact, this is good practice whether towing or no. Not to mention how bloody irritating that up and down shifting is on a long hill.

 

I vote with the 'you'll be fine, especially if you have a fluid change after' faction.

 

Enjoy the trip, stop often (read the roadside Histerical markers), take lot's of rest stop breaks (change drivers each time), and enjoy the trip. OH, I aweddy said that didn't I?

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in neutral the pump probably isn't circulating any fluid since the torque converter and oil pump shaft wouldn't be spinning. makes sense to me what benebob is seeing. engine does the same thing when the coolant quits circulating (engine turns off). surface temps increase since coolant quits circulating.

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Just to post a follow up... we successfully made the move with no real issues. At one point I thought I smelled something burning, but it turned out to be a ripped axle boot spewing grease (grr... 2nd one in a year)

 

I guess I'll never know how "close" i got to the limit since I don't have a temp gauge for the tranny, but everything "seemed" normal. the car has since gone in for it's 90k service where all the fluids got changed anyway.

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I'd go for the ATF cooler but if there isn't enough time I'd change the fluid after the tow.////

 

What he said. If it was mid-summer, different song.....

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I just got the largest tranny cooler i could find.. ;)

it was actually cheaper than the mid sized one...

the box said "suited for full sized RV's"

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