Anyone find a good aditive that helps with milage or anything?
Does any aditive help at all? other then winter fuel jelling?

I use Stanadyne. Used it since new so couldn't tell you what I've gained. All I can say is that the truck in 55K has a life to date average close to 18mpg. I get around 18mpg on my daily commute and typically over 20mpg on the highway at 70mph. I've never had a fuel related issue on any of my diesels which have all had additive pretty much since day one.

It's more of a peace of mind for me. I'm sure there will be others that say you're wasting money.

http://www.dieselplace.com/forum/showthread.php?t=177728

Stanadyne is the only additive that has GM's approval.

K thanks guys