I hooked it up to the top “passenger” side tranny line that goes into the upper connection of what I’m assuming is the radiator/factory trans cooler. (And of course, I didn’t take pictures before putting everything back together)
That’s the thing, though… I found 2 connectors/ports. One at the top passenger side and another at the bottom driver side. I cannot find anything anywhere online that shows which line goes to and from the tranny.
I couldn’t find a single install video or guide for my year or generation Yukon 5.3 (XL or otherwise). Even the install video from Derale (one trailer.com) is for a 2007.
Does your radiator look like this? Photo taken from ACDelco's website of a 2017 Tahoe without Enhanced Cooling.
This photo from Rock Auto website shows Enhanced Cooling Radiator.
The radiator above, the view is from the driver's seat looking forward. Those two lines/fittings on your left are for the engine oil cooler. The two lines/fittings on the right are for the transmission oil cooler. An external transmission cooler connects to the top right line and then goes back to the transmission.
Now having said that, on a K2, your generation truck, the factory external transmission cooler is built into the top of the AC Condenser. So make sure you don't have that already.
Oh, almost forgot, your K2s have a transmission thermostat to keep the temperature nearly the same as the engine coolant. This shortens the life of the transmissions and the remedy is to "flip the pill". Google it.
This is how Mishimoto plumbed theirs:
https://www.tahoeyukonforum.com/thr...14-silverado-sierra-1500-trans-cooler.104487/
