Finally replaced the bypass valve in my brothers 2014 Ram a three weeks ago. He started noticing that his is temps were spiking higher than normal(even for 100F outside temps) when he was hooking up his RV several weeks ago with the truck running in park for just 5-10 minutes and the trans temps got up past 200F. He also started seeing that his temps rose higher than normal when in park longer than five minutes in other situations as well. Towing, his temps would get to the 190F's when they usually were well below that. This led us to believe that the thermostat in this valve was acting up like mine was causing the higher than normal temps.
He did his first tow to Rockport a few weekends ago. Temps never got past 170F towing in 90-95F heat where previously it would get closer to 190F. Unloaded, temps stay around 150F where they were 170F to 175F before. The big test was going across the ferry. He was in line for 30 minutes and his temps never got past 180F where before they would have gone past 200F.
My temps are a little higher than his in the same conditions since I have much higher line pressure than he does due to having a trans built to handle 700 hp.
This time I took pictures of the OE valve since I replaced it for him. As you can see, the line going to the cooler is blocked by a thermostat causing a major restriction. I heated the valve up passed 170F and it barely opened to allow fluid to flow. The Revmax valve (which I didn't take a picture of) is a flow through design like the cooler to transmission side of the OE valve is, but much larger diameter port allowing more fluid to pass through to the cooler unrestricted.
The top of the valve.
From cooler to trans port, trans side.
From trans to cooler port, trans side.
From trans to cooler port, cooler side.
