Catman

Lightning bolt on dash but not the engine light. The problem that I feel is that the truck is not going into gear good first/reverse. It will go in gear with a clunk then seems to work fine. I also can’t switch between n2/n1 while lightning bolt is on. It only stays on for a day or two then goes out and all issues are ok with going into gear. Almost 400k on truck. Any ideas? Thanks in advance