I have a 03 ram with automatic transmission, it has trouble shifting out of 1st gear. It stays in 1st at about 3300 rpms for a while (maybe 6-8 seconds) then finally shifts into 2nd. I am new to this forum and this is my first real truck, just upgraded from turbo imports. So I know next to nothing about diesels. I did a search on here and found someone had the same problem i am having (more or less) and they changed something called a valve body. Does anyone know if this will fix my problem, or have any advice on what the problem may be? Also, just curious, but what exactly does a valve body do? Thanks.