quote:
Originally posted by TallPaul:
heyjay: I'm hoping to get your opinion/advice on the following oil for winter use in the Detroit area. I rarely get below zero F around here. I would be running it in my '95 Ford 300 straight six that has been running 10w40 all winter. The oil is Valvoline Durablend 15w40 (PCEO) and the cold properties are:
pour: -36C
CCS cP: 5700 @-20C
MRV TP-1 cP: 17000 @-25C
In comparison, the Valvo Maxlife 10w40 I was running is:
pour: -36C
CCS cP: 7000 @-25C
MRV TP-1 cP: 21000 @-30C
Hard to compare with the different temps of measurement
BTW, are there other 15w40 PCEOs or is Valvo Dura the only one?
Thanks, Paul
Hello Paul:
Remember that "pour point" has no relevance at all to cold flow. I'm not even sure why they list it.
Based on the limited values you had access to, I would guess the two oils are comparable.
I've never seen a PCEO in 15W-40. Only HDEO in 15W-40.
To compare your values, let's contrast several Esso XD-3 HDEO and some limited data I have about the CI-4 Mobil Delvac 1 5W-40:
CCS:
Esso XD-3 15W-40 6,500 cP @ -20 C
Esso XD-3 0W-30 5,900 cP @ -35 C
Esso XD-3 0W-40 5,900 cP @ -35 C
Mobil Delvac 1 5W-40 6,100 cP @ -30 C
Valvoline Durablend 15W-40 5,700 cP @ -20 C
Valvoline MaxLife 10W-40 7,000 cP @ -25 C
MRV:
Esso XD-3 15W-40 33,000 cP @ -25 C
Esso XD-3 0W-30 11,200 cP @ -35 C
Esso XD-3 0W-40 14,900 cP @ -35 C
Mobil Delvac 1 5W-40 32,000 cP @ -35 C
Valvoline Durablend 15W-40 17,000 cP @ -25 C
Valvoline MaxLife 10W-40 21,000 cP @ -30 C
As you can see, although the CCS values are quite close for Esso XD-3 0W-30 / 0W-40 and Delvac 1, the MRV values are quite different at the same test temp. Comparing Esso XD-3 0W-30 to Delvac 1 represents 1/3 the flow resistance.
That said, I also know of folks running the 300 I-6 with heavier oils in winter no problem. Do you have a good mechanical oil pressure gauge?
Check to see how quickly you build oil pressure.
Any unusual noises? Especially KNOCK KNOCK KNOCK or CLACK CLACK CLACK? If you don't have noises, and don't feel that you "might" have a fuel economy issue (Which I doubt), then carry on.
Hope this helps.
Jerry