Farm Equipment - 30wt VS 15W40 oil pressure

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30wt VS 15W40 oil pressure

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Category: Allis Chalmers
Forum Name: Farm Equipment
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URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=130949
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Topic: 30wt VS 15W40 oil pressure

Posted By: SteveM C/IL
Subject: 30wt VS 15W40 oil pressure
Date Posted: 05 Nov 2016 at 11:01pm

Is it likely that you have higher hot oil pressure with 15W40 over straight 30wt? 15W40 is supposed to act like 40wt hot so that would make sense.Just wondered. I put 15W40 in my 220 last winter and used it for all fall work this year.It runs just under 60psi WOT and I could swear it use to only make 50 with the 30wt but,it's been about 6 years since it really got worked and I got CRS.
The 8070 is out of commission for the time being,ergo using the 220.

Replies:

Posted By: CrestonM
Date Posted: 05 Nov 2016 at 11:11pm

Uh oh...another oil pressure thread! Batten down the hatches!!

Posted By: DrAllis
Date Posted: 06 Nov 2016 at 12:07am

Not been my experience. 30 wt will carry a couple more pounds of hot oil pressure than 15W-40 does.

Posted By: Lars(wi)
Date Posted: 06 Nov 2016 at 6:28am

Years ago, I owned a delivery truck (IH 2155 w/ dt466) that did alot of slow idle with a pto, in the summer I ran 30w, in winter 15-40, it alway's showed higher pressure even in the hottest day's with the 30w that it did in the winter with 15-40.

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I tried to follow the science, but it was not there. I then followed the money, and that’s where I found the science.

Posted By: Gary Burnett
Date Posted: 06 Nov 2016 at 7:13am

I run 15W-40 diesel grade oil in every engine I own and when I change oil the first time in a tractor I buy the oil pressure almost always increases,of course i don't have any way to know what was running it when I bought the tractor.

Posted By: ac45dave
Date Posted: 06 Nov 2016 at 7:20am

CrestonM wrote:

Uh oh...another oil pressure thread! Batten down the hatches!!

I think we're all pretty safe now.the arrogant know it all, that caused all the havoc lately and took threads off topic and turned them into his own personal pi$$ing match was suspended and shut down last week. Thumbs Up

thanks moderators.

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54 wd-45gas ; 56 wd-45d N/F w/fact p/s ; 63 d-17 sIII N/F gas ; 60 D14 N/F ; 67 d-17 sIV N/F gas ; 63D15 sII W/F; 39rc#667 ; 2021 massey 4710 fwa ; gravely 2 wheel tractors

Posted By: Dan73
Date Posted: 06 Nov 2016 at 7:21am

CrestonM wrote:

Uh oh...another oil pressure thread! Batten down the hatches!!

2x LMAO

Posted By: ac45dave
Date Posted: 06 Nov 2016 at 7:25am

i always found in my own experiences, straight weight oil to carry a little higher pressure than multi weight oils.

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54 wd-45gas ; 56 wd-45d N/F w/fact p/s ; 63 d-17 sIII N/F gas ; 60 D14 N/F ; 67 d-17 sIV N/F gas ; 63D15 sII W/F; 39rc#667 ; 2021 massey 4710 fwa ; gravely 2 wheel tractors

Posted By: steve(ill)
Date Posted: 06 Nov 2016 at 7:51am

the straight weight might have a slightly higher pressure than the 15w40. "Theoretically" they should be similar , but remember, the multiweight is a combination trying to solve multiple problems. The main advantage of a 10w30 or 15w40 is not the pressure when HOT, it is the advantage of thin oil when COLD to get the oil flowing quicker.

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Like them all, but love the "B"s.

Posted By: SteveM C/IL
Date Posted: 06 Nov 2016 at 8:51am

DrAllis wrote:

Not been my experience. 30 wt will carry a couple more pounds of hot oil pressure than 15W-40 does.

That would have been my guess too.Kinda why I ask.I guess I'm okay with what it is but am a little puzzeled.