I run a warmed 150kw TD42T in front of my RE4 with stock TB45E J6 TC and Nomad valve body. I tow 2.7t caravan no problem.
I rebuilt a spare RE4 years ago with extra clutches but it’s still sitting on the shelf waiting for the current one to give up.

If I had to guess I’d say something wasn’t put back together properly but it’s likely to not be anyone’s fault as usual..