Have a 2004 3500 4x4..5.9..automatic ..transmission shifting from 1st to 2nd wants to shift back to first and stay there. Then finally shifts after taching very high.. sometimes I have to let out of it to get it to shift...in the past it has wanted to hold in second for a while then shift...but this automatic down shifting is driving me nuts... anybody have any suggestions..?

 

Mileage? Maintenance history? Checked the fluid level and condition?

 

Fluid is good.. replace filter and fluid about a year ago

 

Has 151,000 miles

 

Drop the pan and see whats going on..

 

Replace the electronics while you are in there.