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markeb01 · 09-17-2009, 10:45 PM

The last time I had an automatic, I also used metal lines, from trans to radiator with no rubber hose. The only exception was when I once used an external cooler and had to use rubber to hook it up. If you incorporate multiple bends, or a loop in the hard line, it won't fracture. I suspended mine in the center of the run with a bracket near the oil pan.

I'd recommend nothing smaller than 3/8". If you're going to use an external cooler do not use one that has 5/16 tube fittings. I did that once and it created so much pressure in the transmission it ballooned the torque converter, which pushed forward on the crank and wiped out the engine block. It was an expensive learning experience.

If you do use rubber hose in the system, either keep it ahead of the fan/v-belt arc, or route the lines inside or against the frame so the possiblity of a broken belt won't rip the cooler line open.

09-17-2009, 10:45 PM	#3
markeb01 Senior Enthusiast Join Date: Feb 2007 Location: Spokane Valley, WA Posts: 8,356	Re: Trans lines The last time I had an automatic, I also used metal lines, from trans to radiator with no rubber hose. The only exception was when I once used an external cooler and had to use rubber to hook it up. If you incorporate multiple bends, or a loop in the hard line, it won't fracture. I suspended mine in the center of the run with a bracket near the oil pan. I'd recommend nothing smaller than 3/8". If you're going to use an external cooler do not use one that has 5/16 tube fittings. I did that once and it created so much pressure in the transmission it ballooned the torque converter, which pushed forward on the crank and wiped out the engine block. It was an expensive learning experience. If you do use rubber hose in the system, either keep it ahead of the fan/v-belt arc, or route the lines inside or against the frame so the possiblity of a broken belt won't rip the cooler line open.