Eaton 6 speed problem please help

Hi everyone,
First time using this forum, I’m hoping someone can help me out here.

I have bought a 2010 freightliner m2 box truck with Cummins 5.9 with a Eaton auto shift 6 speed tranny. I’m having horrible trouble with the transmission.


When I bought the truck almost 10 months ago it, every now and then when reversing it would start to make an awful noise, ( almost like something was trying to engage but couldn’t) took it to the shop after 5 weeks I finally got it back. They sent the transmission to ULT powertrain in Moncton to get rebuilt, new clutch was installed at the same time. drove truck for 2 months, 2 weeks ago I came to a set of lights. Pulled away got approx 50 feet and the truck locked up solid! I couldn’t move forward, reverse. Almost like the brakes locked up. I checked playing with the gear selector and finally after 10-15 mins I put it in low gear and it moved. Worked ok for about a week. Now it has a noise every time it upshifts, and it’s delayed, almost like it searching for the gear before it engages. ( sounds like something is still spinning between shifts, also now pulling away on any hill, the truck won’t shift out of first. It tries to shift into 2nd, and it’s so delayed and drops by down into 1st again. It keeps trying. Took it to shop they told me it’s the x-y shifter. Just replaced it, same thing. Very frustrate! Will be calling the dealer tomorrow to tell them that bill they will need to look after because I’m getting fed up with them throwing parts at it.

Any info would be greatly appreciated.