Quote:
|
Originally Posted by docsg
Thanks RockyMtnRay for your informative post. I'm going to just head out and nix the cooler. I see your point in that a 7" x 7" cooler will not help much until you operate at a significant speed and since my trailer is in the "small" category, I'll "chance" it. B&M makes a thermostat operated unit w/fan that probably puts the OEM Toyota unit to shame and it is 1/2 the price of what Toyota wants for theirs. A service technical that works for Toyota told me "off the cuff" that the Tundra tranny coolers were crap compared to other truck brands and aftermarket units so you can see how I was beginning to get confused by the conflicting information I was getting. Your post made sense to me and I'm going to just head out. I would like to order the B&M or Derale fan units but I don't have time before I leave. The truck has only 10K on it and it is 1 year old. If I screw up the transmission, I'll let Toyota repair it then sell it as I want an O5' anyway. Again, thanks for the great advice!
P.S. To the moderators--thanks for the information about "moving my original post." Might I suggest that an email be sent to the person originating the thread simply denoting that it has been moved (and to where). To be honest I never even thought to look in the section where it was moved but appreciate you informing me that that's where the original went. I just got through reading the posts to it (also very informative) and you can simply "kill" this one if you want to and don't worry about having to merge them.
|
Yeah...you should be fine without the external cooler as long as
you make sure the transmission torque converter stays locked. The transmission doesn't generate much heat as long as that TC is locked...but as soon as it unlocks and you start getting torque conversion/slippage, a
lot of heat gets generated.
The best way to insure TC lock is to simply turn off the OD...that allows TC lock in 3rd gear and given your fairly small/light trailer in combination with the relatively low altitudes and mild grades of your trip, 3rd should provide more than enough towing power.
One of the more startling revelations I've had while towing is how closely changes in transmission temperature track to engine load even with the torque converter locked (so the tranny itself is not generating much heat at all). I eventually concluded that under light engine load, the engine's coolant thermostat is mostly closed, therefore the coolant at the bottom of the radiator (where the transmission's primary oil/water cooler is setting) is really rather cool. However, under high engine load (again with the TC locked), the thermostat opens and the temperature of the coolant at the bottom of the radiator rises quite a bit...up into the 150 to 165 range if the ambient is over 90. A corrolary conclusion is the factory external cooler is really only dropping the ATF temperature by about 5 to 10 degrees...a definite help but not a huge one...which corroborates what the service technician told you.
As for PMs to thread originators re thread moves, if time permits and we remember to do so, we mods often do send a PM. But since this is volunteer work and we're pretty busy folk, that doesn't always happen. When in doubt, use the search functions.