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Tranny cooler/external filter really needed?

1820 Views 13 Replies 7 Participants Last post by  Rubizuk
I have been doing some research on aux. tranny coolers and am trying to decide if I need one.

Maybe some of you saw my thread about the odd shifting into drive issues with my 05 rubi LJ auto, after changing over to amsoil. I will be switching back to atf+4 asap and hopefully that will be the best idea, unless someone recommends something else? It has 50k miles, fluid was clean before the amsoil too.

I know that it is a good idea to add a cooler for towing, and long heavy pulls on hilly roads, but still wondering if I need one. It is my DD, and now mostly around town and highway here and there. Then of course wheeling trips (driven to and from trails 1.5 hours away, and then a few trips per year out of state, 10-15 hours away) where I use it what it is made for. I know rock crawling puts more stress on the tranny and probably heats the fluid up quite a bit more, especially in 95+ degree florida heat. But will a cooler help this? It wouldn't have much air flowing through it at crawl speeds, but does the clutch fan solve that? Or would it need an aux fan attached to the cooler too? I was reading the thread about trans running too cool and that it is sometimes pointless to have a cooler (especially if a thermal bypass valve is used).

I am just lost on the whole cooler issue and if I should get one, which one is ideal and fits properly? Thanks for any advice! I want to get this settled before my next harlan KY trip in april. Thanks!!!
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Are you running bigger than stock tires? Judging by your sig, I'd say yes. Then Yes, a tranny cooler is a great idea. Heat kills them QUICK.

Best of Luck,

Mike
Yes, running 33x12.50s right now.

Ok, but from reading other threads, alot of times the tranny temp never goes above what it was designed to operate, especially ones that have a cooler with an thermal bypass valve. I heard that sometimes it may never even flow into the cooler if it has the valve.
I think that they are always a good idea, whether you're towing or not. It's cheap insurance to keep the trannys cool and the aux AT coolers are cheap. Another plus is our tranny line hook ups, at the radiator, are stupidly easy, compared to other manufacturers. Do I have one installed yet? No, and being busy addressing all my other issues is really no excuse. It is on my short list but, it will have to wait until later, due to the weather and other issues. If, you really want to get your head swirling, research and look at the pros and cons of mounting the aux tranny cooler before it enters your radiator or after it leaves it.

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Wow thats a nice unit! Anyone have one of these and have any ideas for the install location?
I have read that its is a good idea but that also depends on where you live also. In florida id say go for it, it cant really hurt ya. That being said I read at that sametime that colder climates could cause some typ of problem due to fluild not heating up. To what degree I am unsure, I dont think there would be much of a problem with it in colder areas.
jfandem said:
Wow thats a nice unit! Anyone have one of these and have any ideas for the install location?
Somweher close to the tranny if you dont bury it in water.
A mate of mine has one bolted to the underside of the hood covered by a Gen-right type grill to suck air in.
itchy said:
A mate of mine has one bolted to the underside of the hood covered by a Gen-right type grill to suck air in.
I am def getting those gen right hood grill pieces...and wow that is a good idea! Do you have any pics or info? How does he run the lines and still be able to open and close the hood?
I'm going to install a cooler, and will order this to mount it:

http://www.offroadtrailtools.com/shop/i ... detail&p=5
itchy said:
A mate of mine has one bolted to the underside of the hood covered by a Gen-right type grill to suck air in.
I am def getting those gen right hood grill pieces...and wow that is a good idea! Do you have any pics or info? How does he run the lines and still be able to open and close the hood?
It was on a Nissan Patrol (dont think you guys get these?) cooler just had slightly longer hoses to allow the hood to open, just make sure to use Trans. hoses and keep it from catching or fouling on any thing as the hood opens.
What about inside the fenders near the firewall (dont know what US spec Jeeps have there, mine has the ARB compressor.
#will try and hunt some pics down
No doubt, coolers are an excellent low cost adder for an automatic transmissions, espeacially if doing alot of low speed crawl type wheeling. I have a small Hayes AT cooler on the power steering I installed in my Samurai. Something else that's even better is proper auto trans service via a closed loop flushing system (BG PF5 type or other). Severe duty (if you wheel your rig) interval would be around 15k miles. Normal everyday driving about 30k. Goes a long, long way towards extending the life of a trans. BG now offers a lifetime warranty (up to some max $$ amount) if the service is performed every 30k miles.
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