I used to know that if I put Mobil Delvac 1 in my Duramax I was getting a great Group IV PAO based synthetic. Later when Delvac 1 became very difficult to find, I thought Mobil 1 Turbo Diesel Truck was the same. It's not. Now I don't know what to buy.
I want to buy a Diesel 5W-40 true Group IV PAO synthetic with a good additive package. Mobil refuses to even tell me what category their synths fall into now and their wear numbers as shown on this site aren't too impressive either so screw them.
I look to Amsoil and it seems they are starting to use the same nebulous language, "blends" and all that nobody can nail down, and at the same time I am reading that they are buying their basestocks from the lowest bidder. This in addition to a call I put in to Mercedes Benz asking why they don't recommend Amsoil and their response that the formulation was too inconsistent. I don't know what that means but I guessed that it means that the formulation changes as a function of the price of the ingredients. (this is just my supposition)
Royal Purple seemed interesting but there are too few people using it and too little data for me to get a handle on.
And then there is Redline which is a group V basestock which is not a durable (long OCI) as a group IV and I really don't want that.
What I really want is what old Delvac 1 was. I want a 5W-40 Group IV PAO basestock synthetic oil.
Does it still exist?
Is there anywhere I can buy an oil like this anymore?
I want to buy a Diesel 5W-40 true Group IV PAO synthetic with a good additive package. Mobil refuses to even tell me what category their synths fall into now and their wear numbers as shown on this site aren't too impressive either so screw them.
I look to Amsoil and it seems they are starting to use the same nebulous language, "blends" and all that nobody can nail down, and at the same time I am reading that they are buying their basestocks from the lowest bidder. This in addition to a call I put in to Mercedes Benz asking why they don't recommend Amsoil and their response that the formulation was too inconsistent. I don't know what that means but I guessed that it means that the formulation changes as a function of the price of the ingredients. (this is just my supposition)
Royal Purple seemed interesting but there are too few people using it and too little data for me to get a handle on.
And then there is Redline which is a group V basestock which is not a durable (long OCI) as a group IV and I really don't want that.
What I really want is what old Delvac 1 was. I want a 5W-40 Group IV PAO basestock synthetic oil.
Does it still exist?
Is there anywhere I can buy an oil like this anymore?
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