I need a tool for transmission temp. I have a Disco 4 and LR insisted no oil cooler. Now with burnt oil and new gearbox. I tow. I will check temp of gearbox oil in new defender and install oil cooler if temp goes above temp set by automotive experts. I need the tool to prove to LR that I need a cooler for heavy towing. They didn't want to know me when their advice cost me $10000 last time.

