- Dec 23, 2006
Why not use a higher HTHSV oil and add GF-6B to it to lower the HTHSV to the desired level? Also, I'm not sure that STP is all that effective at raising HTHSV.
Originally Posted By: ExMachina
The main point here is that GF-6B oils will have better boundary lubrication performance, since that oil will be at a low HTHS (for fuel economy). We like the boundary lube superiority of a GF-6B, but want to add a slightly higher HTHS (to about 3.0) for the typical load carrying oil film strength we also want. Therefore, raising HTHS slightly in a GF-6B will give us BOTH great boundary lubrication AND thicker oil films. Thats the last time I will explain that.