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Viscosity: Going Down!

From Blackstone Labs, The Oil Report, February 2017, article attached:

... more diesel fleets going to 10W/30, ... Not only will the bearings do just fine, but the engines will start up better (especially in the cold).  And this change might eliminate the need for plugging your diesel in at night.

Re: Viscosity: Going Down!

Reply #1 –
I run Rotella T6 5w-40.
1998 U270 34'

Re: Viscosity: Going Down!

Reply #2 –
 From the oil report;
"Additive levels have been lowered in engine oil and the old flat-tappet engines still run great."

That's true but I make sure the ZDDP is 1,400 PPM in the case of my classic SBC.

Re: Viscosity: Going Down!

Reply #3 –
Have been running 0w30,0w40 in gas powered vehicles for 20 years plus.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Viscosity: Going Down!

Reply #4 –
+1 on Rotella T6 5W40
Dave and Kelli
1997 U295 40' Build #5188 CSGI
1995 U240 36' Build #4621 SBID-SOLD
2006 Jeep Wrangler Rubicon

Re: Viscosity: Going Down!

Reply #5 –
Interesting- our 2013 Subaru Outback calls for 0w-20 which we have used all the time since new- no problems at all.

Amsoil new diesel oils are lower viscosity, primarily made for the newer diesels to meet EPA regulations.

Has anyone with pre 2007 engines switched to a lower viscosity diesel oil and if so, what are your results?  I have read a number of articles about switching to 10W-30 diesel oil but so far have stayed with the tried and true 15W-40 for my Cummins ISC350.  Might be something to look at??
Ted & Karen
2001 U270 36' - sold after 12 years full timing

Re: Viscosity: Going Down!

Reply #6 –
I'm with Ted & Karen on the subject of; "Has anyone done it and what were the results?"
More oil consumtion, less oil consumtion, leaks............etc.?

Re: Viscosity: Going Down!

Reply #7 –
I've always been a believer in  "stick with the gal that brought you to the dance." I've used Delo (even non-detergent in my Land Rover) on all heavy working business rigs since then. I don't keep much track, but after having three coaches (all diesel), I'd say, I'm like John S.; "close to 400,000 miles". All with Delo 400LE SAE 15W-40.  ^.^d
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: Viscosity: Going Down!

Reply #8 –
Quote from: mike leary –
I've always been a believer in  "stick with the gal that brought you to the dance."

I tend to think along the same lines. Our 1995 Cummins M11 was designed to operate on 15W-40 and has performed remarkably well. Why would I even consider changing?
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Viscosity: Going Down!

Reply #9 –
I am running Mobil1 Turbo Diesel Truck 5w-40 synthetic diesel oil in my FT engine and genset.

My 2017 Subaru forester calls for 0w-20, but I put in 0w-30 because I have read many reports of high oil consumption in these subarus, and all the WRX enthusiasts run thicker oil, so I went ever so slightly thicker. Wont know the results of this change for 15 years or so, but thats OK with me. My GF has a new Mazda 3 and the manual says 0w-20 in USA, 5w-30 rest of world. Mazda clearly uses 0w-20 to meet USA fuel economy standards but prefers a 5w-30 where fuel economy doesnt matter, so I am also using a 0w-30 in that. Keep the cold starting benefits, and slightly more viscosity when hot.

I'm not really concerned with cold starting of the RV engine. The whole point of the RV was to stay away from those ridiculous arctic conditions, at least for me! That said, I know a lot of the 10w-30s provide plenty of protection and are taking over the market. I wouldnt be opposed to switching, but the 5w-40 works great for my needs, and I have enough of it stockpiled to last a lifetime.
95 U300SE

Re: Viscosity: Going Down!

Reply #10 –
I will try to find the info that I had on multi-weight oil. As I recall the higher number is how much anti thinners are put into the oil. It doesn't get any thicker than the lower number.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Viscosity: Going Down!

Reply #11 –
Quote from: craneman –
I will try to find the info that I had on multi-weight oil. As I recall the higher number is how much anti thinners are put into the oil. It doesn't get any thicker than the lower number.
I think the higher number of a multi-grade oil is the normal viscosity at ~210deg & the lower W number is its equivalent at ~40deg.  So, a 5W30 is the viscosity of a single grade 30 weight oil at operating temperature but performs similar to a how a 5 weight would perform at cold temperatures.

Re: Viscosity: Going Down!

Reply #12 –
RVtrvlr, someone said to me a while back that the oil degrades after a year and esp' if it gets really cold- like close to freezing.
 ^.^d
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Viscosity: Going Down!

Reply #13 –
Sorry John, but thats simply not true. Been reading Blackstone reports for years and they successfully ran a 50?ish year old ebay oil in an 80s truck. It performed fine based on analysis. The stuff has been in the ground for millions of years, five years is Mobils official position, but I know itll be good for ten times that.

http://www.blackstone-labs.com/Newsletters/Gas-Diesel/October-1-2013.php
95 U300SE

Re: Viscosity: Going Down!

Reply #14 –
My walmart brand gear oil has the goodies settle to the bottom if it sits on the shelf a while. But the dinosaurs are still in good shape!
1998 U270 34'

Re: Viscosity: Going Down!

Reply #15 –
Shake it like a spray paint can before using.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: Viscosity: Going Down!

Reply #16 –
I installed Shell Rotella T6 5W40 in March of 2016, driven 3600 miles since with no oil used. I also noticed the antifreeze overflow container was down half a quart when checking the oil level. Not sure what this means!
I installed AMSoil HD Diesel oil, 15W40 in January 2011.
By March 2016, had driven 25,000 miles using a quart every 2000 miles, which is normal according to Cummins.
I did notice faster cranking when cold with Rotella.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: Viscosity: Going Down!

Reply #17 –
May be the difference in 5w and 15 wt.
96 U270 BUILD 4810
85 380SL
Drummonds TN.
 

Re: Viscosity: Going Down!

Reply #18 –
Rotella T6 5W40.
 My choice in the engine, generator, and hydraulic reservoir. 

1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.