[jdmccright]

The amount of cooling you get from the brief period the fluid runs through a steel line is minimal compared to the fluid running through an actual cooler. Sorry, but keeping it steel won't make that much difference in the lifespan of the tranny. The only reason GM used the steel/rubber combo is to make it fast & easy for the assembly line to hook it up and be reliable for the warranty term while giving enough flexibility to account for production variance. To me simpler is better.

It is inevitable that the OEM crimped steel/rubber lines will leak, whether they be for oil, tranny fluid, etc. All 4 are leaking on my '95. I've gone to cutting the original crimped hoses off and using a flaring tool to create a bubble flare to use with standard tranny fluid hose and a screw clamp.

Dunno where you live at but dry rotting of oil lines is a very long-term problem in general (up to 10 years). If you want to protect them further, you can install some braided hose cover or the split-type engine wiring harness plastic over them. And tie them away from other heat sources.

If you're tranny fluid is getting too hot and you don't have one already, then consider an external tranny fluid cooler.

Hope this helps!