I just baught an 20 hd, what oil does everyone run? I was thinking about ansoil, any suggestions?

 

To be honest, you could run it on any oil (even Wally Mart cheap stuff) as long as you changed it regularly along with the filter.
Just stick with a name brand and follow the factory instructions on weight and service interval.
Personally, mine has Castrol semi-syn 5/20w because thats what the dealer uses.

 

I run Valvoline Synthetic

 

The synthetics really can't be beat, except on value. Amsoil and Redline???yes, they're great. Mobil1???yes, it's great and readily available. Food for thought???Motorcraft semi-synthetic meeting the 903 spec for under $2 per quart and readily available.

 

I'd go with a name brand synthetic like Mobil 1, Amsoil, etc.

 

Spend a few bucks and use fully synthetic. Cheap insurance. These motors have pretty tight tolerances. I use Mobil I 5W30 as do many many others in this community.