Recent Topics
putting on auxillary speakers
by 928 - 01/29/20 02:51 PM
The "benefits" of low unemployment
by Egg_Head - 01/29/20 01:47 PM
What ever happened to the Focus RS engine problems?
by jayjr1105 - 01/29/20 01:05 PM
Motul vs Shell
by yagciogullari - 01/29/20 12:20 PM
2011 -13 Prius
by WhyMe - 01/29/20 12:15 PM
Mixed feelings about retirement
by carviewsonic - 01/29/20 12:04 PM
2 yr old M1 0W-20 AFE. Still good?
by jharrison - 01/29/20 11:51 AM
1965 Mustang 289 - Recommended oils
by Mossyoakglock - 01/29/20 11:22 AM
Avast antivirus selling user data
by xfactor9 - 01/29/20 11:04 AM
Quality wheels
by meborder - 01/29/20 09:59 AM
topping off coolant
by snake123 - 01/29/20 09:15 AM
Check your TSC stores.
by D1dad - 01/29/20 08:32 AM
School me on tread design and performance
by MoneyJohn - 01/29/20 07:43 AM
What style refrigerator do you have?
by ZZman - 01/29/20 07:29 AM
Julianne Hough, Wildfire...
by mattwithcats - 01/29/20 07:21 AM
Battle for the lowest price for T5 15w40 back on
by paulswagelock - 01/29/20 06:36 AM
Pressurized Well Tank & Digital Control
by GON - 01/29/20 06:33 AM
Toyota haults production due to Coronavirus
by Rat407 - 01/29/20 05:50 AM
Jay Leno-- Honda 50/Cub Memories
by csandste - 01/29/20 02:47 AM
Newest Members
CNT, Subthedom69, mag3, mosschops, indigo2020
70555 Registered Users
Who's Online Now
112 registered members (1978elcamino, 28oz, AandPDan, 750IX, AlaskaMike, 928, 8 invisible), 2,097 guests, and 18 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics300,707
Posts5,181,662
Members70,555
Most Online4,538
Jan 20th, 2020
Donate to BITOG
Print Thread
Hop To
Page 1 of 6 1 2 6
Higher viscosity = higher operating temps? #5205699 09/05/19 07:15 PM
Joined: Sep 2010
Posts: 8,235
2015_PSD Offline OP
OP Offline
Joined: Sep 2010
Posts: 8,235
Has anyone seen an oil temperature increase by moving from say an xW-20 to an xW-40 (with everything remaining the same)?


2019 o)|||||(o Rubicon Wrangler Unlimited 3.6L V6 [Castrol Edge + Mahle]
2018 Mercedes Benz C300 2.0L Turbo [Pennzoil Platinum + Mann filter]
Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205764 09/05/19 08:50 PM
Joined: Dec 2002
Posts: 43,484
S
Shannow Offline
Offline
S
Joined: Dec 2002
Posts: 43,484
Yep,
5W20 to 25W60 in my Briggs and Straton makes quite a difference.

That was an air cooled engine, so you won't see a coolant temperature change.

My old J-Car, lost a few MPG going SAE30 to 25W70...that's ALL oil related heat.


If it's the truth....it can handle the pressure !!!
Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205792 09/05/19 09:29 PM
Joined: Dec 2017
Posts: 3,238
J
JLTD Offline
Offline
J
Joined: Dec 2017
Posts: 3,238
I went from 5w-20 to 0w-40 (with 5w-30 in between) in my 2013 F150 (5.0), with no discernible difference in mpg or power.

I imagine going to a 70 (! dang Shannow) might have made a difference....there's thick, then there's TOO thick.


"Let’s not pretend like 0w20 is anything but a CAFE required crutch to eek another 1/2MPG" - BLND1

Hers: 2018 Ford Flex AWD EB, 35k, dealer fill

His: 2015 4Runner 60k, SS 5w20/Amsoil

Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205829 09/05/19 10:53 PM
Joined: May 2019
Posts: 3,513
M
Mad_Hatter Offline
Offline
M
Joined: May 2019
Posts: 3,513
Originally Posted by 2015_PSD
Has anyone seen an oil temperature increase by moving from say an xW-20 to an xW-40 (with everything remaining the same)?

I'd say the new Xw-40 lube isn't moving as freely (reduced flow) throughout the engine, as compared to the previous Xw20 lube? You would get more heat if the oil film weren't as thick as the previous lube but I would expect that to happen (potentially) if you went down in viscosity, not up.

I suppose it's possible to see a noticeable rise in oil temp related to oil drag..too thick of an oil can actually increase wear (rate) on some components.

Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205832 09/05/19 11:09 PM
Joined: Aug 2018
Posts: 1,054
RDY4WAR Online Content
Online Content
Joined: Aug 2018
Posts: 1,054
Yes. Street stock engines running 5000-7000 rpm sustained at near WOT the entire time. On 20w-50, the oil temp hangs around 280*F. On 10w-30, it never tops 260*F.

In my own car, sticking with 5w-30 all year around produced the same 220-230*F oil temps all year around. Going to 5w-40 in the summer increased temps to near 240*F.


"He who is without oil, shall throw the first rod." - Compressions 9:1
Re: Higher viscosity = higher operating temps? [Re: Mad_Hatter] #5205847 09/06/19 12:50 AM
Joined: Aug 2015
Posts: 1,349
paulri Offline
Offline
Joined: Aug 2015
Posts: 1,349
Interesting question. Since the answer appears to be yes, then why is this the case? Is it that the engine has to work harder, to push through a thicker oil? Or is it that a thicker oil will absorb heat better? If I understand Mad Hatter correctly, he is saying that it is the first--that the engine has to work harder?

Originally Posted by Mad_Hatter
I suppose it's possible to see a noticeable rise in oil temp related to oil drag..too thick of an oil can actually increase wear (rate) on some components.


2005 Toyota Sienna LE; 163,000 miles
2006 Toyota Highlander Hybrid 118,000 miles
Re: Higher viscosity = higher operating temps? [Re: JLTD] #5205848 09/06/19 12:54 AM
Joined: Jul 2003
Posts: 5,397
S
Silk Offline
Offline
S
Joined: Jul 2003
Posts: 5,397
Originally Posted by JLTD
I went from 5w-20 to 0w-40 (with 5w-30 in between) in my 2013 F150 (5.0), with no discernible difference in mpg or power.

I imagine going to a 70 (! dang Shannow) might have made a difference....there's thick, then there's TOO thick.


Currently have 15W-60 in my Volvo, and no noticeable in crease in temp or fuel consumption...that's just using a temp gun on the sump, and it has a heat exchanger in the top tank, so basically running at coolant temp. In fact my best ever fuel consumption has been done on the 15W-60 - 7 litres per 100km for 100km open road...33.6 mpgUS., 40mpg UK.


1987 BMW R65 - Penrite VTwin 20-50
2005 Nissan Expert - 5W-30 Castrol Edge
1996 Volvo T5 - Penrite HPR15 - 15W-60. Ryco syntec filter.
Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205853 09/06/19 01:26 AM
Joined: Sep 2015
Posts: 2,757
Z
zeng Offline
Offline
Z
Joined: Sep 2015
Posts: 2,757
It's rpm driven under light load condition , IMHO.

Re: Higher viscosity = higher operating temps? [Re: Silk] #5205858 09/06/19 01:57 AM
Joined: Oct 2015
Posts: 3,321
F
FordCapriDriver Offline
Offline
F
Joined: Oct 2015
Posts: 3,321
Originally Posted by Silk
Originally Posted by JLTD
I went from 5w-20 to 0w-40 (with 5w-30 in between) in my 2013 F150 (5.0), with no discernible difference in mpg or power.

I imagine going to a 70 (! dang Shannow) might have made a difference....there's thick, then there's TOO thick.


Currently have 15W-60 in my Volvo, and no noticeable in crease in temp or fuel consumption...that's just using a temp gun on the sump, and it has a heat exchanger in the top tank, so basically running at coolant temp. In fact my best ever fuel consumption has been done on the 15W-60 - 7 litres per 100km for 100km open road...33.6 mpgUS., 40mpg UK.


Wish i could get Penrite in Spain, specially some HPR30 20W-60...
Just the thought of that lovely bright stock base with 1600ppm of ZDDP makes my mouth water slobber

Last edited by FordCapriDriver; 09/06/19 02:00 AM.

1975 Ford Capri II Ghia 3000 V6 - Repsol Elite Super 20W-50
1988 Ford Escort XR3i Cabrio - Repsol Elite Super 20W-50

Re: Higher viscosity = higher operating temps? [Re: zeng] #5205859 09/06/19 02:15 AM
Joined: Jul 2003
Posts: 5,397
S
Silk Offline
Offline
S
Joined: Jul 2003
Posts: 5,397
Originally Posted by zeng
It's rpm driven under light load condition , IMHO.


No one achieves best fuel economy at max revs and wide open throttle...max manifold vacuum is best. But I never got better economy with lighter oils in the same conditions. And as they say - ''Your results may differ.''

Last edited by Silk; 09/06/19 02:16 AM. Reason: A capital a was required.

1987 BMW R65 - Penrite VTwin 20-50
2005 Nissan Expert - 5W-30 Castrol Edge
1996 Volvo T5 - Penrite HPR15 - 15W-60. Ryco syntec filter.
Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205860 09/06/19 02:18 AM
Joined: May 2019
Posts: 3,513
M
Mad_Hatter Offline
Offline
M
Joined: May 2019
Posts: 3,513
Originally Posted by paulri
Interesting question. Since the answer appears to be yes, then why is this the case? Is it that the engine has to work harder, to push through a thicker oil? Or is it that a thicker oil will absorb heat better? If I understand Mad Hatter correctly, he is saying that it is the first--that the engine has to work harder?

Tolerances determine the ideal viscosity..too thick of an oil and starvation and drag (resistance) can be a problem; too thin of an oil and oil film thickness can become an issue in preventing metal to metal contact.

The thicker the oil, the harder the engine has to work to push that oil through the engine, filter etc. This (engine working harder) will cause an increase, on some level, of engine temps. This is also why high viscosity oils are not designated resource conserving (increased fuel consumption). In addition, higher viscosity oils have larger molecules and when an oil ages and the lighter molecules burn off you have a high(er) concentration of those larger molecules (think sludge) that can cause wear in areas of tight tolerance (think bearings). Now synthetics are designed to have uniform molecules that better withstand thermal breakdown as compared to mineral oil. The higher the quality of the synthetic base oil, the more uniform the molecules are and better thermal stability. I believe that the same holds for the type and quality of the viscosity modifiers used.

I'm just a regular Joe trying to relate stuff I've read, so if I've got something wrong please chime in.

There's a lot out there on oil drag but here's some stuff that you might find useful..

Viscosity

Viscosity 2

Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205897 09/06/19 04:22 AM
Joined: Jul 2003
Posts: 5,397
S
Silk Offline
Offline
S
Joined: Jul 2003
Posts: 5,397
Oh, so that's all good then, my 15W-60 is ester POA and the uniform molecules are what give me the better fuel economy.


1987 BMW R65 - Penrite VTwin 20-50
2005 Nissan Expert - 5W-30 Castrol Edge
1996 Volvo T5 - Penrite HPR15 - 15W-60. Ryco syntec filter.
Re: Higher viscosity = higher operating temps? [Re: Silk] #5205902 09/06/19 04:34 AM
Joined: May 2019
Posts: 3,513
M
Mad_Hatter Offline
Offline
M
Joined: May 2019
Posts: 3,513
Originally Posted by Silk
Oh, so that's all good then, my 15W-60 is ester POA and the uniform molecules are what give me the better fuel economy.

Or even if you're running a grp2 oil, just don't push it past it's break point...oil that's breaking down is going to increase the operating temp and rob your engine of hp, fuel efficiency and increase wear rate.

Last edited by Mad_Hatter; 09/06/19 04:36 AM.
Re: Higher viscosity = higher operating temps? [Re: paulri] #5205912 09/06/19 04:51 AM
Joined: Dec 2002
Posts: 43,484
S
Shannow Offline
Offline
S
Joined: Dec 2002
Posts: 43,484
Originally Posted by paulri
Interesting question. Since the answer appears to be yes, then why is this the case? Is it that the engine has to work harder, to push through a thicker oil? Or is it that a thicker oil will absorb heat better? If I understand Mad Hatter correctly, he is saying that it is the first--that the engine has to work harder?

Originally Posted by Mad_Hatter
I suppose it's possible to see a noticeable rise in oil temp related to oil drag..too thick of an oil can actually increase wear (rate) on some components.



People get enamoured with the pumping and "flow"...that' not it. Pumping is less than turning on your headlights.

The real losses are in viscous drag in the bearings (and bearing surfaces like piston rings)...in fact, some OTR engine designs of the future will include thermal barrier coatings in the mid stroke area to artificially reduce the viscosity in the mid stroke region.


If it's the truth....it can handle the pressure !!!
Re: Higher viscosity = higher operating temps? [Re: 2015_PSD] #5205929 09/06/19 05:16 AM
Joined: Jun 2015
Posts: 5,678
V
Virtus_Probi Offline
Offline
V
Joined: Jun 2015
Posts: 5,678
I keep the oil temp up on my MFD and I definitely noticed an increase in temps the first time I used a higher HTHS 5W30 (M1 ESP Formula, HTHS was 3.58 compared to the vanilla M1 5W30 I had been using at 3.1). I don't remember the exact temp ranges anymore, but I think I posted at the time that they went up 5-10F with the ESP.
Since I was used to seeing fairly consistent temp ranges with some dependence upon the seasons (typically a bit cooler in the winter) over some tens of thousands of miles and I made this change in the summer, I was pretty alarmed to see the temp range move up all of a sudden. I actually posted a panicky thread about it on subaruforester.org and some knowledgeable folks there let me know that was exactly what was to be expected...more viscous oil, higher oil temps.


2014 Forester XT, 111000 miles
Last Change;
M1 0W30 AFE
Tokyo Roki 15208AA170 filter
Page 1 of 6 1 2 6
Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™