$7.99 a qt at JC Whitney. Just FYI

 

I don't see it on their site. The thinest weight they have is 5W-30.

 

How do oil weights work? What do the numbers mean? Thanks

 

The way I think of it is:

* The lower the numbers are. the thiner the oil is.
* The number in front of the "W" is the viscosity at start up.
* The last number is viscosity at full operating temp.

So, 0W-20 would be thiner at start up and operating temp , than, 5W-30 oils. Don't flame me, this is how I understand it is. Please correct me, if I'm wrong.

Peace,
Paul

 

Let's take 0w-20 oil as an example.

0 is the viscosity of the oil at -35deg C (-31deg F). Water has the same viscosity as zero weight oil.

20 is the oil's viscosity at 100deg celcius (212deg F). The oil gets thicker at higher temperatures to protect the engine.

Source: http://en.wikipedia.org/wiki/Motor_oil#Multi-grade

 

So 0W 10 would be thinner than 0W 20 and possibly yield higher FE. Has anyone done a test of 0w20 vs 0w10 in an HCH to confirm this?

 

I'm having some difficulty accepting that assertion. There are so many mechanical and environmental factors involved that unless you have an implanted an OBD-II interface, Borg-style, I think what you probably sense is what you want to sense.

That said, a lower viscosity oil will probably get you some gain in mpg-efficiency, but at what cost? It is very expensive, and you have more friction at operating temperatures.

 

I doubt it, although I suspect it does save some gas. But the REAL question is "Is 10-weight oil TOO thin to protect my car's gas engine?" I suspect it may be. I wouldn't run it solo in any car I own. At best, I might consider a 50-50 mix of it and Mobil1 0w20 in my Hybrid, since I know it was DESIGNED for 0w20 (so a 0w15 blend might be safe). But I wouldn't even do that until very late into my (extended to 120K) warranty. Any issues - and a subsequent warranty denial - will KILL your gas savings.

 

This is my first post, however, I changed my engine oil in a 92 jeep cherokee laredo 4x4 with 240,000 miles on it. ( I did NOT like adding zinc for camshaft protection). I used RP 5w-20 and a mopar filter. I could tell an IMMEDIATE difference. The weather was lower than 20*f snow, ice etc. I always got 13 & 14 MPG ( doing the math), the MOST MPG I EVER got was 18, no a/c, windows up,warm weather, etc.

IN THAT cold, in 4x4 d/t snow and ice, mileage went to 17.? and 19.?...this is including 10 minute warm up times. NOW the weather has gotten warmer, soooo, filled 2 days ago and got 20.43 MPG from a 4x4 4.0 jeep !!!!

My honda hybrid in the summer, gets 47.? MPG, winter, if I am lucky I'll get 39 / 40.

I am ordering RP 0w-10 for it now. The ONLY detrimental thing I can see is the HTHS levels will reduce the catalyst conversion efficiency over time, RP literature states that the additive package in their oils REMAINS in suspension and is retained, ( 3 months / 1 year quicker reduction errosion ? ). on THAT NOTE, a 25% co2 reduction from EVERY properly tuned and in fuel control-ed modern EFI vehicle can be obtained by eliminating the cat's on these cars ( not by me).

I used a 4 gas on several vehicles, properly running and in fuel control. WITH cat 15.5% co2, 0.00% co, and under 100 PPM hc's......same vehicles WITHOUT cat 12.3% co2, 0.00% co, under 100 PPM hc's.....hmmmmm

just something to ponder

 

The HTHS additives will reduce wear. The PRESSURE @ idle does not matter in an ICE engine 10 psi @ idle is PLENTY, 10 PSI for every 1000 rpm is the "accepted" oil pressures. Who cares about resistance to flow ( pressure) as long as it is high enough to keep metal reciprocating parts from making contact. instantaneous flow throughout the ICE is whats nessesary for longetevity (sp?)

BTW...I have been running 0w-10 in my 400 HP pro street cat for 5 years now, ZERO wear last winter when torn down for a "refresh" of ANY worn parts....wasted gaskets is all I did.