Technically the 20w50 doesn't cool better. It has a higher viscosity at higher temperatures. If your engine is running say 240 degrees or higher, the film strenght/thicknes will be thicker for the 20w50. So you would have better protection during high heat times.quote:
Originally posted by sunruh:
please explain how a 20w50 is gonna "cool" the motor so much more than 15w40 is when oil is a poor coolant to being with???
and then, please tell me how this heat absorbing 20w50 then gets rid of all that energy, because it can't hold it forever!
Redline oils are very superior oils. No doubt about it. What do you use in your primary?quote:
Originally posted by Fatboymoe:
When I had my 98 FLHT, the oil pressure with Mobil 1 15-50 was ok, but would go down to about 5psi at hot idle. I do realize that roller bearing motors don't require a lot of oil pressure, but 5psi used to scare me. I changed to Redline 20-50, and doubled my hot idle oil pressure. If I had to use a HDEO in a pinch, I wouldn't waste any time changing it out. On my 03 Fatboy, I use Redline 20-50 in the winter and 20-60 in the summer. The TC motors have a much more modern oil pump assembly, which is better in every way compared to the EVO oil pump assembly. Higher flow and pressure are necessary because of the piston oil squirters.
BMW's have a separate Engine and Transmission oil. As far as going longer, I don't know about that. I've gone over 6,000 on my Triumph (shared sump) and I've seen several long distance touring riders on goldwings go over 10,000 miles. So I don't think that having a shared sump is a factor.quote:
Originally posted by Jim 5:
MSparks,
Did your BMW have a shared sump? My understanding is that many of these BMW's have separate transmission oil, which enables you to go longer on an engine oil change.