engine oil, whats best?

[Diesel JD]

Currently running a couple auto-RX and rinse cycles with Valvoline Blue and then to 15w-40 Amsoil Marine and Diesel.
Also nothing but good things to say about Rotella it seems to protect more than adequately I've run mostly 15/40 rotella but also some SAE30 rotella. Now if you wanna find something that is CI4 or older compliant I'd think that stuff would be the ticket...haven't looked lately though. I ran some Pennzoil Longlife in my rig as well, but I was less than impressed with how much blowby and increased oil consumption I had with it especially near the end of the interval, ditto for Carquest's storebrand.

 

[typ4]

The problem is less zinc in the additive package, rotella has a bit more than the others. If the jug of any of them say" low e" as in emmissions there is little to no zinc, which is a great anti scuff additive.
Also ,I dont see too many big rig turbo's coking up with dino diesel oil ,because it is designed for the heat. Now standard car oil is another story. I run delo or rotella in the vw engines and the temp drops 10 degrees average over even good racing oil so, they get diesel stuff.
my 2 c

 

[Agnem]

Yup. I was ticked about this switch. I think we are past the point now where when you read the label and it says "recommended for all diesel engines" they are not talking about us anymore. I think the general assumption is they are no longer going to take into consideration anything older than 20 years. Unfortunately though, to the best of my knowledge pre 6.0 liter engines still need zinc and phosphates too last a long time too, so I've had to switch the whole fleet to Brad Penn. I posted about this problem a while ago in my API Alert thread.

 

[Papabear]

my rule of thumb is I will use whatever is common in the stores.
Delo or Rotella is good. I tend to find Delo more frequently, so I go with Delo.
Synthetics imho is nothing but trouble if you ever wind up in a situation where you will need to stop somewhere and buy oil.

amsoil claims to mix readily with any oil without complication