Hi Guys: Thank you for making me look up some information. Your conversations and questions have made me take a new interest in my own trade. I tried to look up in Mitchell’s and Alldata today to find the correct oil pressure of a 4R100 trans. NOT LISTED – so I called the transmission shop that rebuilds all of our transmissions and asked what the oil pressure should be? After going through two technicians, no one new. I did learn that Hayden Corp has a list of trans. temps on there coolers which states that 175 degrees will get you 100,000 miles – 195 / 50,000 – 220 / 20,000 - 240 / 10,000 and any hotter is death to your trans. I also found TFT (trans. fluid temp sensor) chart by Ford, it list from 40 below to 267-302, the high reading has no spec. last spec listed is 231-266 that reads .8 to 1.5 ohm’s middle of the chart is 105-158 and the spec for that is 5-16 ohm’s. My belief is that about 150 degrees is about what will give you the best life of your transmission. The Mobil salesman was in today and I ask him for the spec. sheet on Delvac and trans. Fluid, keep watching and I will get you the right oil pressure at every condition and temp. By the way, I found out that our transmission has a CBV – that stands for cooler bypass valve and is mounted on the side of the trans. It also has a second line that hooks the outlet to the inlet incase the cooler plugs up. And there is only one outlet to test pressure at and it is called line pressure which is controlled by the PCM and even the A/C can change that pressure. As I get more info. I will give it to you. Happy bird day Mike OB
