Interesting link on diesel oil ratings

Hi Abus,

Take a look at Delvac Super’s VI and HTHS, also the pour point, in each and every facet the Delvac Super is proving to be superior to others and coming quite close to the synthetics surprisingly. In terms of HTHS, the Delvac Super is proving to be superior to the Amsoil synthetic which is quite credible considering the Amsoil product is rated to be quite good. It was your post about HTHS ratings that got me into thinking that under severe high temperature operating conditions, HTHS and VI should be the topmost criteria for any good diesel engine oil. Even in matter of TBN, the Delvac Super is bettering its synthetic Delvac-I cousin and that is no mean feat. Sadly Delo 400 which I consider to be excellent diesel oil didn’t give its HTHS rating as it would have been interesting to compare it to the Delvac Super. All in all, thanks to you, I got interested in HTHS ratings apart from VI and therefore gained this valuable insight into the world of diesel engine oils.

The Rotella S is avaialble here but I didnt like the performance of the previous Rotella diesel oil so didnt try it out. Maybe I will give it a try.

I think that it isn't easy to correlate low wear numbers or long drain capabilities with the small differences in starting HTHS and TBN between Delvac 1300S and the others. There are several different methods of measuring TBN, such that if you send a virgin sample to 4 different labs, you will likely get a range of numbers. As a side note, the real question for long drain intervals is TBN retention, which is an area where Delvac 1 definitely wins.


I agree that regular Rotella T 15W40 seems overpriced for an acceptable, but not outstanding product. Since the same parent company makes the rather excellent Penz Long Life, and it is the cheapest of the major 15W40's, it seems like an easy decision to me!

The 5W40 Rotella "Synthetic" is interesting though, at $12/gallon it offers a good bit of the performance of Delvac 1.

http://www.shell-lubricants.com/products/pdf/RotellaTSynthetic.pdf

http://mobil.com/USA-English/Lubes/PDS/GLXXE2CVLMOMobilDelvac1_5W-40.asp

Having said all that, I like the Delvac 1300S.

Since there has been lots of favorable reviews of Delo 400 Isosynth, I have decided to give it a try,yesterday I had a long conversation with the local regional manager of Caltex and even though he went into lots of details, even he couldnt give me the HTHS rating of this oil. Anyways I have decided to give it a try and will keep you guys updated on the situation.

I normally use the Delo 7,000 km in my light vehicles on dirt roads, 500 hours on farm equipment, and 20,000 km on highway trailer trucks on paved roads through the mountains.
I use oil analisis to monitor these levels and maintain extremely low wear metals.

Widman,

Many thanks for your information about Delo 400, since both my diesels are older generation engines, I would expect less soot deposti on them so the Delo 400 should be good for 7000Km/6months intervals.