Upgrading transmission cooler lines. 2004 LJ
 

Hi there,

My transmission cooler lines on my LJ with the 42RLE have developed some real bad corrosion so I intend to replace them. Looking at the factory routing of these lines, it puzzles me as to why they run within an inch of the exaust pipes and along the length of the engine. I would figure cooler lines especially for a transmission would be ran in a way to avoid any sources of heat.

So in a effort to improve this I plan to replace most of the factory steel lines with 3/8" Goodyear HR5 high temp(300F) hose commonly used in air brake applications on larger trucks and route the new lines along the frame rails and eventually meet up with the rad. I plan to replace the steel factory fittings at the transmission with common brass plumbing fittings to accept a standard 3/8" flare and run new steel lines out of the transmission and transition to rubber between the transmission and the chassis instead of at the front of the engine. At the same time I plan to install a B&M temperature sensor in the cooler return line.

Would appreciate any input or ideas that anyone has to offer on this.