Winter will be here soon - starting to think oil cooler thermostats again

[bobcowan]

Don't drive below 50*?? Really?? Last week end the temp was right about freezing when I started out. The Lambo in our group had a little trouble starting, but I don't think any of the Cobra's did.

My oil cooler has a seperate pump. So in normal street driving it's like not having a cooler at all. As the day wore on and the air temp got warmer (like 55-60*F), the water temp stabilized at about 180*, and the oil temp was about the same. We were pushing it a little hard over some of the mountain passes.

Before I started using a seperate pump, on a day like that with the cooler blocked off I the oil would not see temps >140* or so on the street, no matter how hard I pushed it. Not having the cooler and associated lines with oil running through them made a big differance.

Synthetic oil does pour easier at lower temps. But we're talking about temps below 0*F. At 40*, a 20W synthetic pours about the same as a 20W dino. That being said, you're much better off with a 5W oil in the winter - just like in your other cars.

Synthetic oils don't run any cooler than dino oils. It's not a function of the oil. Synthetics just handle high heat better, which is a whole differant issue.

Most engines don't need a 20W-50 oil, especially in the winter. Unless you're racing. In that case, you take pains to pre-warm the oil before starting and racing. For street driving, you need enough viscosity to maintain proper pressure. Thicker/heavier/higher viscosity just wastes energy, and makes the engine more difficult to lubricate.

I run 5W-30 in the winter with no problems at all. In the summer and racing I switch to 10W-40. That works well for my engine.