oil change

Sully2 wrote:

WILDEBILL308 wrote:

427435 wrote:

WILDEBILL308 wrote:
The problem with running a oil with higher viscosity than recommended is todays engines are not your fathers engines. The internal tolerances are much tighter than those built 50 years ago. The rod bearings in your V10 Std Size Oil Clearance: 0.0011/0.0023 in. main bearing oil clearance 0.0001 - 0.0018. When you run a higher viscosity oil you don't get proper lubrication.
But you can run what ever you want in your engine I won't have to pay any money for repairs. I would run Mobil 1 0-20 if it was my engine.
Bill

Like many others, you are confusing reduced tolerances with reduced clearances. The minimum clearance that a certain bearing will successfully run at has not changed. But with tighter tolerances, more bearings are closer to that minimum tolerance (nor are there as many bearings that are "loose."

Well actually I do know what I am talking about. In this case we are talking about the oil gap. The bearings will be out of tolerance when they exceed the max dimensions listed. The oil gap is much tighter in newer engines than in the past and require a lower viscosity oil for proper lubrication.
You jump in on this by trying to talk about the manufacturing tolerance.
Bill

REGARDLESS of the thickness of the lube..the BEARINGS remain the size they were machined at!

Well there agene you are wrong Sully. Bearings wearer with use that is why you have to rebuild engines. When they reach a point where they no longer control oil flow they need to be replaced. In the case I posted earlier you would need to replace the main bearings if the oil gap was 0.002. Let me try to explain this a different way for you. If you have a gap of 0.001 and a gap of 0.006 which one would 50 weight oil flow through faster? Now if you were concerned about getting oil through the smaller 0.001 gap wouldn't it make sense to use a 20 wt. oil?
Bill