Originally Posted By: BrocLuno
Depends on whether it has gone through a wax stage separation during a long cold spell. Oils that have a paraffin content can separate if they cool at just the right rate and stay cold (below zero) for a prolonged period.
If you pour one out and it comes out with waxy lumps, it must be re-heated to 180* F and stirred to get it all back together. Can be done on a hot plate in a pot. Nothing wrong with the oil, it has just separated.
I suspect some folks saw this years ago and thought everything had fallen out of suspension ... But it does not work that way. Once heated and mixed, it's as good as new
Interesting. Would it be possible to just put the lube into the crankcase and let the engine mix it up?
1) drive your car/truck to heat up the engine to full temp
2) OCI; old lube out and the "new" (separated) lube in
3) drive it around again for perhaps 20+ minutes; fully warming and mixing the new lube
Would not putting the separated oil into a warm engine not have the same effect as a hot plate? The key to this would be the sump temp, right? Doing this on a hot summer day with a fully warmed engine would probably have the desired result, whereas doing this on a cold winter day may not get the oil pan warm enough to melt the wax enough?
Now, granted, if the oil came out of the jug in total clumps of wax, it would not be a good idea. But if the lube has only small wax separation, would it not work?
I cannot imagine that there would be harm to the engine, presuming a fully warmed state at the beginning. It may not be optimum for the first few minutes, but I don't believe the engine would be irreparably damaged.
Thoughts?