I found a PDF for the drain down radiator test to see if the lower section is clogged. Problem is that the pictures are low quality. Anyone have a source for better pics or added input? I am also unclear if the cause of transmission cooler failure is only from radiator clogging or can the transmission cooler fail on the transmission fluid side? Thanks.

This is my old rad, removed from car, hose in top hole, this is the flow from the bottom feed to the gearbox cooler



This is the same with a new rad...



Trans cooler can fail internally and put water in gearbox, it can also get blocked with old dirty oil and the pipes often collapse internally and block flow...

If you having gearbox overheat problems I'd do the lot, new engine rad, new oil cooler, new oil cooler, oil cooler thermostat and manifold and new cooler lines...

Admin note: this post has had its images recovered from a money grabbing photo hosting site and reinstated  Pete

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2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Thanks. No issues yet and I want to be proactive on these things. 120k miles on it now. PO was not first owner and doesn't know if it was ever changed.