This 5w20 application chart is a joke!

[427Z06]

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Originally posted by TallPaul:

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Originally posted by 427Z06:
Why be a wimp? Move up to Red Line 25W70 and show us you have some guts.

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And add two bottles Synpower Oil Treatment just in case it's on the thin side of a 70 weight?

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Why chance it still being to thin? Why not use straight Valvoline Synpower Oil Treatment?

 

[Gary Allan]

Ah, Dr. Aehaas! Glad you could join us. We haven't heard from you in a while

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It is arrivederci, Gary.

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Hey, blame Google. It corrected my mutilation of the word(s) and asked me if that is what I meant

They need lessons too

As my mental faculties decay I find myself depending more and more on google to find the obscure stuff that a normal spell checker just can't help with

The normal stuff I just misspell

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Hey I like ol' ***Wee, he knows his lubes.

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Allegedly so

 

[TallPaul]

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Originally posted by 427Z06:

quote:

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Originally posted by TallPaul:

quote:

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Originally posted by 427Z06:
Why be a wimp? Move up to Red Line 25W70 and show us you have some guts.

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And add two bottles Synpower Oil Treatment just in case it's on the thin side of a 70 weight?

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Why chance it still being to thin? Why not use straight Valvoline Synpower Oil Treatment?

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I like it. Definitely would get some good ZDDP values! Bit expensive though. May have to revert to Walmart Oil Treatment (presumably a clone of STP).

 

[cousincletus]

FWIW I have seen a few late 1980s, early 90s 300 inline sixes that had main bearing problems. Some just wore out too soon for some reason.

 

[TallPaul]

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Originally posted by cousincletus:
FWIW I have seen a few late 1980s, early 90s 300 inline sixes that had main bearing problems. Some just wore out too soon for some reason.

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I suspect a weak oil pump relief valve spring is causing my lower than spec pressure with a 30 weight.

 

[JAYCEE]

I just started my ARX 2nd rinse w/ 15w40. I think that I will give MC 5w30 a try this winter to see if the MPGs go up a little.

 

[Gary Allan]

Lower pan ..or other access method to said spring. Remove spring. Stretch spring or add washer behind spring (proper end). Replace spring.

Enjoy higher peak pressure.

 

[TallPaul]

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Originally posted by Gary Allan:
Lower pan ..or other access method to said spring. Remove spring. Stretch spring or add washer behind spring (proper end). Replace spring.

Enjoy higher peak pressure.

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If I go so far as to have the pan pulled I will have a new pump installed--or in the least, a new spring. But 40 psi is acceptable vs the cash outlay for the new pump and, if it isn't the pump, I will have wasted the money. So until the hot pressure is getting too low I'll just stick with 10w40. Who knows, maybe it has looser bearings. But I would think if the engine was worn it would show up in other areas, such as oil consumption and that is zero, literally, not even a drop in the level on the stick through 4200 miles.

 

[JohnBrowning]

Mitch the old rule of thumb was usualy to start with a base oil presure number of something like 25-35 psi at idle and then add 10 psi per 1000 RPM's added to that base number. If the engine is a low rpm engine a bypass is not really needed if the engine's RPM limits peak oil pressure. If the RPM potenial is high enough and the oil pump is designed to exceed the minimum then an oil bypass system is designed in. Most OEM applications bypass some place between 65psi and 150psi.

 

[TallPaul]

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Originally posted by JohnBrowning:
Mitch the old rule of thumb was usualy to start with a base oil presure number of something like 25-35 psi at idle and then add 10 psi per 1000 RPM's added to that base number.

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Yep and my idle pressure is about 18 hot on the F150 I6. Now, my motorhome 460 V8 is a textbook example of good oil pressure: 75 cold, 60 hot at 2000 rpm, and 30 hot at idle. And that on 10w30.

 

[427Z06]

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Originally posted by JohnBrowning:
Mitch the old rule of thumb was usualy to start with a base oil presure number of something like 25-35 psi at idle and then add 10 psi per 1000 RPM's added to that base number. If the engine is a low rpm engine a bypass is not really needed if the engine's RPM limits peak oil pressure. If the RPM potenial is high enough and the oil pump is designed to exceed the minimum then an oil bypass system is designed in. Most OEM applications bypass some place between 65psi and 150psi.

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JB, get off the crack. It's bad for your health.

 

[Gary Allan]

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But I would think if the engine was worn it would show up in other areas, such as oil consumption and that is zero, literally, not even a drop in the level on the stick through 4200 miles.

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I agree, if the bearings were shot you would show some symptoms elsewhere. I think that you're in good shape.

There are some oil pumps (I forget the particular installations) that have access to the pressure relief via the oil filter mount. There it is truly a matter of a couple of screws and stretching the spring out ..stuffing it back in ..and ~voila~ instant higher peak pressure. Now it don't do squat for your hot idle reading ..but..

 

[427Z06]

My Toyota 7ME service manual says that anything above 4.3 psi at idle is acceptable.

 

[JohnBrowning]

427Z06, Specific applications are going to be all over the place. We are talking about general rules of thumb that have been used since shortly after the inception of the internal combustion engine. More and more often this old general rule is being left behind for a lot of reasons. One of the main issues is crank case size, rpm potenial and sump size. Then you add in newer bearing material and new material matrix's. Today you have two very different stratageys for oil mangement. Some engines are biased toward volume while others are biased towards pressure.

To add insult to injury you also have more then one standard for any given engine. It is common for the engineers to set the limits at a different point for warranty worj then what the service manaul actualy states.

I am almost positive that the RPM potenial of your Supra is the reason for the low idle oil pressure. You see this on Corvettes and other performance vechiles as well. What is the bypass presure 90,95,110,120 psi??? As a matter of fact the idle and operateing oil pressure standards for my Buick 3800 exceeds the oil requirments for a Corvette.

 

[TallPaul]

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Originally posted by Gary Allan:
I agree, if the bearings were shot you would show some symptoms elsewhere.

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Like maybe the 476 ppm lead in my latest UOA?

 

[theguru]

Arrivederci Baby -The Movie

 

[Gary Allan]

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quote:Originally posted by Gary Allan:
I agree, if the bearings were shot you would show some symptoms elsewhere.

Like maybe the 476 ppm lead in my latest UOA?

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Whoa

(imagine semi cowpoke type leaning on a fence post - perhaps with blade of grass in his mouth - tipping his hat back) "Say, mighty fine lead reading you got thar"

 

[427Z06]

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Originally posted by JohnBrowning:
Specific applications are going to be all over the place.

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JB, my point exactly. One needs to look at the specs for the engine before one starts to decide what is acceptable.

 

[Eddie]

Maybe you have a faulty oil pressure gauge OR you may have gotten an engine built at the outer limits of acceptable tolerances. Check your oil pressure gauge first. Ed

 

[TallPaul]

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Originally posted by Eddie:
Maybe you have a faulty oil pressure gauge OR you may have gotten an engine built at the outer limits of acceptable tolerances. Check your oil pressure gauge first. Ed

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Good point. I recently verified the used AutoGauge in my F150 by slipping in a brand new Sun gauge and got the same readings at a handfull of rpm levels. Also slipped in a used Sun gauge and it also was close to the AutoGauge.