Tranny Codes
Last year my tranny was shifting hard up and down in 4th, I picked up a code that the speed sensor was going bad or had a bad connection. I had Covington Diesel (the Allison/Detroit Bank and Trust in this area) install a new speed sensor and then changed the two small filters in the tranny for about 150.00 lew bucks. This was about a year ago and I am still burning fuel. If I have used the retarder, it will still shift hard.
Check for codes before spending big bucks.
Roger that!
2008 Liberty DS XL2
2023 Denali Ultimate
My 6th Prevost