Originally Posted By: BoostFiend
Originally Posted By: Gary Allan
Quote:
I am little confused by your calculation. Since the viscosity is figured at 32 degree's for the "winter" weight (5 vs 20 weight) and 212 degree's Fahrenheit ( 20 vs 50 weight), I don't see how a 5w-20 can be thicker then the 20w-50 weight at any same given temp.
I merely pointed out that if, as you suggest, a 20w-50 would harm his engine due to tight clearances ..and let us for the moment that he is operating in a 95F environment over the summer. Oh ..he may get a dip to 85 on occasion ..but his standard temp during the summer is 95F ..now if you look at the 40C spec's of a 20w-50 ..you'll see the 104F viscosity. Now just dial in the temp that makes a typical 5w-20 THAT SAME VISC ..and you're looking at 50F. Hence, if a 20w-50 is going to harm his engine with him starting at (near enough) to 95F ...then the EXACT SAME liabilities are experienced by EVERY 5w-20 user at 50F.
Do they have troubles with their HLA's and whatnot?
No, they don't. So, WITH THE QUALIFICATION of limited starting temp usage, he's at NO RISK of the things you alleged. That is, unless 50F starters also suffer from that (5w-20)oil's use.
Here's what people tend to gloss over. Every oil out there transitions through a very broad span of visc from whatever temps to whatever temps ..from Canada to Texas ..from -40-100f+
That's why when someone says "people have reported problems with VTECH when using a 5w-40" ...I ask "Do they have troubles if they hammer it too early out of the driveway with lighter oils"? Otherwise, what they really mean is "They have trouble until they fully warm up.".
NOW ..and AGAIN, I think that he would use a 5w-20 and be happy and confident. Using a 20w-50 will have him wasting fuel for no good reason churning very heavy oil.
Not really sure how what your saying is relevant , I am not talking just about start up, most the time the car is running the oil is going to be near full operating temp at that time the oil will be to thick for the lash adjusters.
Do cold 5w-20 engines experience HLA issues? The oil is allegedly too high for them too
..and all cars running on 5w-20 are operated for 20 minutes and never start @ freezing or below freezing? Do they experience HLA issues? If they don't ..they are seeing conditions that a 20w-50 car can ...in say ..Texas with 75f-100F startup temps.
Let's take "Jake" the retired Crown Vic owner in Frostbite Falls MN. Every day Jake goes to Mom's Apple Pie diner for coffee. It's 6 miles away. He starts his 5w-20 Crown Vic @ -25 and experiences no HLA issues ..even though his 5w-20 is several magnitudes above a 70 weight at startup and, since Mom's is only 6 miles away, only reaches 100F oil temp. He appears to have no HLA issues ..and no one expects him to. Why? Because they say he's using the approved 5w-20 oil.
Now Jake's cousin, Texas Tommy, has the exact same routine, but he lives in Texas, uses 20w-50, and goes to Sally's Spicy Cafe ..same 6miles and he reaches a 150F oil temp. Does he experience HLA issues? Some say that he should ..but he's experiencing the same conditions that Jake is. How can he have these issues if Jake does not?
The relevancy is simple. Anyone who tells you that using one grade will "cause" (fill in the blank) is obviously looking at it from a one dimensional view and not thinking it out to far.
So .....for our OP ...given some seasonal qualification for ambient temps ..why would 20w-50 cause him "issues"??
Now (and for the 3rd time - just to assure you that I feel he should) I think that he should use a 5w-20. His cost savings in fuel kinda make it a good thing.
