Hey guys....
I have a 03 tacoma 4X4, V6. i was wondering what you guys suggest for transmission coolers for towing about 5000 Lbs. for my truck. Thanks for any help!

I do suggest a tranny cooler for any rig with an auto tranny that will be towing. I've done a little tranny work and can tell ya that heat is the death of almost all auto trannies.

Get a stacked plate cooler rather than the bigger, less effective tube and fin coolers. Hayden makes some good ones, get the biggest one you can fit in. I've seen them at Pepboys but online is cheaper. Try e-bay, here is one: http://cgi.ebay.com/ebaymotors/HAYD...QitemZ8021209767QQrdZ1QQsspagenameZWDVW

Without reading that whole ebay ad, if that's the same size as the TRD tranny cooler, I can say the size is perfect. I've 4wheeled in sand in the summer and the tranny temp didn't go over 220 - well inside the safe zone on the chart. <img src="/forums/images/graemlins/kewl.gif" alt="" />

I would fab some real brackets instead of using zip ties on a 4wheeler <img src="/forums/images/graemlins/baby.gif" alt="" />

Curious question. My wifes car runs the tranny fluid through a coil inside the radiator to cool it; does Toyota not do the same? I've got the manual so I can't go look. <img src="/forums/images/graemlins/zombie.gif" alt="" />

Yep, same design. The aftermarket cooler taps into those lines.

Yes, this is for extra cooling above and beyond what the radiator cooler can do. On mine I run the ATF through the factory radiator cooler then through a Hayden cooler before the return trip to the tranny. It will also help if you put in a cooler thermostat so your coolant isn't running quite so hot.

Hayden Part No. 678 or 679 - either one. Both are of the stacked plate design, too. Pep Boys sells them for about $60-$70, but I've heard of people getting them on ebay for about $30-$40. Summit Racing sells a bunch of different trans coolers, too.

Also, it helps to buy extra trans cooler hose - but make sure it is labeled as transmission cooler hose and not something else, like fuel line. Fuel line is not designed to handle hot, 150-250 degree fluid. And the bigger the hose diameter, the better.

It's true that a stacked plate design dissipates heat more efficiently than a tube and fin design. However, a tube and fin design is much less restrictive with flow than a stacked plate design. Flow restriction is also a tranny killer, but most stacked plate designs do not restrict the flow so much to risk starving the tranny of precious fluid and pressure to the point of damage, unless you run two or three in series. The best setup is a big tube and fin cooler with an electric fan and shroud in which the core is at least 1.5" thick (the Hayden 678 and 679 cores are only 3/4" thick for comparison). But unfortunately, it's not only expensive ($150-$400), but it's also very difficult to fit in front of the Tacoma's a/c condensor without major cutting and modification.

An old school trick is to get a good, clean a/c condensor from a salvage yard and run it as a tranny cooler, but you have to make sure it's super clean inside and has not suffered "black death" damage, otherwise you'll be contaminating the transmission with blackish gunk and possibly killing it. Also, most a/c condensors are huge, which obviously makes them excellent heat dissipation units, but also makes them hard to fit behind the front grille of a Tacoma.

Hope this helps.

Here is next cooler I'm going to get: http://www.importperformancetrans.com/coolers.shtml

The self regulating design sounds like it would be worth the extra $ IMHO because it has less flow restriction when cold. My BMW ATF cooler has a simalar design.