08 F450 transmission issue

[ASPILL]

I have an 08 f450 that is doing some interesting things. It runs normal, without a trailer. As soon as I start to haul something, the transmission won't down shift properly. The RPMs go way down, without down shift help. It will do this in tow mode and without it in tow. Does it sound familiar to anybody. It is completly stock, and has 110,000 miles

thanks aaron

[merickson]

Doesn't sound familiar, but I would almost guess a bad or sticking shift solenoid from increased pressures in your tranny when towing, hope this helps.