I have a 05 2500 diesel with a slush box. Unit has 174k on it. A month or so ago a line pressure code came up . After 2 weeks they (Dodge service)figured it out , governor solenoid and some harness inside trans was replaced.
A week ago another trans code came up, P 1753 I believe, now the shifting is not right , first to second shift at almost 2500rpm .
I bought an extended warranty when I bought the truck but it only has about 5000 miles until it’s done. Now they will do an adjustment and replace a part or two , then say it’s fixed. Most transmissions don’t last 170000 miles but the truck was never used , it was a pavement princess until I bought it. Now I think they should replace the unit but they don’t want to do that because of the cost.
Glad I bought the truck, performance is great, fully loaded with over a cord of hardwood it crawls out of the forest and gets me home. A little more light on climate controls would be nice and the alarm that goes off if something is not right.

 

Something to do with the trans throttle valve, which is electronic.... Fair few things could be wrong, and yeah, I am pretty sure that "Age" has a fair bit to do with it. And pavement princess or not, 170K miles, is 170K miles.