Recommended Transmission Cooler for 2001 Toyota Sienna

Question:

I see a number of listings for a transmission oil cooler for 2006 Toyota Sienna. I plan to do some moderate towing and generally would liek to extend my trans life by assuring that it gets a cool drink on hot days...I just purchase dthe Sienna so Im not familiar with the hot setup but have been cautioned by my local trans shop that the stock small cooler is a weak link on the 06 sienna.....Please advise. My location is norteast, MAss / Nh so we do get cold in winter,. If the set up is to install a second cooler then I will probably plumb it in a manner that allows me to close a valve to only use the single oem cooler in winter....probably a couple of custom braided lines and fittings...Please advise. Thanks No specific timeframe in mind for this modification...better to get it right when I do it. Thanks

asked by: Peter

Expert Reply:

For your Sienna, given your location and the fact that you describe your planned towing activity to be moderate, I'd recommend a middle of the road option, the Derale # D13501. The cooler is large enough to be effective for moderate towing, but not so large that you'll be waiting forever in the winter for the transmission to warm up.

It's recommended to install the aftermarket cooler in the return line from the radiator back to the transmission. I personally wouldn't recommend installing a bypass valve because the valve could easily be forgotten. I believe you'd need to install a valve in the line from the radiator to the aftermarket cooler and in the line from the after market cooler to back to the transmission. A bypass would join the two valves. I've linked you to a video showing a cooler being installed on a similar vehicle. I've also linked you to some FAQ articles about transmission coolers that you might find helpful.

expert reply by: Mike L