Only (2) choices in synthetic 15W40?

496 BB

Head Thread De-Railer
Feb 20, 2009
697
5
18
44
At your girlfriends house
Bout due for my first oil change since Ive owned truck (only has 36k miles) and want to run a synthetic. Ive read a BUNCH on the net about oils in the past few days but seems only schaeffers and Amsoil make a synthetic in this weight and I think schaffers is a blend not full.

I have ALWAYS ran Mobil 1 in my 8.1L and its still kicking like new with 178k on the odo. Im very particular in preventive maintenance and due it religiously. I know most of it is prolly in my head but again thats my head so Im running a synthetic. Im not worried about the cost of an oil change. I didnt buy a $40k used truck to be a cheap ass on important things such as an oil change.

I tow 8k lbs most weeks and have it deleted. Ive always been skeptical of Amsoil mostly due to their high pressure sales tactics and more importantly (and Im not sure if this is true anymore or not) they were not certified by whatever board that certifies oils. Correct me on that if so please. I do run it in my sport quad but I also change the oil after every 2 rides too so not much to see there.

As does everyone I just want to start this thing out on the right plan for the future. I keep my trucks for a long amount of time and want whats best in an oil. Please share thoughts and facts and or studies so I can make a decision. Appreciate it!
 

Max Attitude

11SIX
Mar 7, 2012
814
0
16
Caledonia, MI
http://www.duramaxdiesels.com/forum/showthread.php?t=56857&highlight=rotella+t6

http://www.duramaxdiesels.com/forum/showthread.php?t=65180&highlight=engine+oil+run

http://www.duramaxdiesels.com/forum/showthread.php?t=44832&highlight=rotella+15w40

I run regular Rotella 15w40 (with Lucas oil additive) as well as many others. Most the oils mentioned in those threads are good. Pick something easy for you to get locally and change it often. I change mine every 5k. Some change it every 3k. I believe the manual suggests every 10k. :eek:
 
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PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,517
501
113
Central OH
5w40 won't hurt anything,
Good oil doesn't have to be expensive,
Non synthetic will protect your engine perfectly.

Want a good high zddp oil? Run some Brad Penn.
 

ikeG

Oughta Know Better
Apr 19, 2011
2,472
152
63
Western PA
www.facebook.com
Schaffers sales rep said their supreme 7000(semi synth) has all the good qualities of both oils but with the advances in dino oil anymore, non synthetic isnt as great of an issue.
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,677
1,947
113
Mid Michigan
If only Schaffers was sold at more places. Id rather run that than anything else. That said, Ive never had issues with Rotella. I just shortened the interval up when running the truck harder. I never let the OLM get below 50% during those years. ;)
 

DefiantArms

Limp Mode Cowboy
Jan 28, 2016
897
1
18
St. Augustine, FL
I didn't know schaffers made the citrol degreaser cleaner that stuff works real good. I've always used rotella but occasionally add something to the mix gives it another 50rpm :thumb:
 

paint94979

Beer Nazi
Sep 18, 2006
11,715
8
38
37
i've ran Amsoil 15w-40 for 60,000 miles... i change every 6-10,000 miles or once a year :D
 

mike diesel

I'm alright.
Sep 6, 2012
4,005
0
36
SLC, Utah
Royal purple makes a full synthetic 15w40 @ $35 a gallon lol!

With that being said, all I run is standard delo 400. My 167,000 motor looked brand new inside when I tore it down for the built motor.
 

THEFERMANATOR

LEGALLY INSANE
Feb 16, 2009
3,890
44
48
44
ZEPHYRHILLS, FL
Just run a 5w40 oil. It will spin over quicker when cold, and oil pressure is about the same as 15w40 when hot. I hold 65-70 cold idle, and around 30 hot idle. Opens the squirters just off idle, and even when its hot out towing, it will still go up to 55-60 where the bypass opens around 2500-2800 rpm's. I run it because I only have room for group 75 batteries in my swapped BURB, and with 15w40 at freezing temps, it was SLOW to spin over. 5w40 took care of it. Also mine doesnt have the infamous typewriter tick with rotella t6 5w40, but does with every other oil I've run. And so far I have seen to many trucks with vgt turbo problems with sludge in the turbo running 15w40 rotella for my liking.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,743
5,911
113
Phoenix Az
biggest issue with reg dino oil is oil temps when towing. they dont like the heat as much as synthetic.

That said, i run reg rotella 15w40 in the winter out here (not really winter compared to most places lol) where my oil temps damn near never get over 230 when towing and swap to 5w40 full syn rotella in the summer for the heat protection. changed every 3-5k or twice a year it seems :D
 

496 BB

Head Thread De-Railer
Feb 20, 2009
697
5
18
44
At your girlfriends house
Just run a 5w40 oil. It will spin over quicker when cold, and oil pressure is about the same as 15w40 when hot. I hold 65-70 cold idle, and around 30 hot idle. Opens the squirters just off idle, and even when its hot out towing, it will still go up to 55-60 where the bypass opens around 2500-2800 rpm's. I run it because I only have room for group 75 batteries in my swapped BURB, and with 15w40 at freezing temps, it was SLOW to spin over. 5w40 took care of it. Also mine doesnt have the infamous typewriter tick with rotella t6 5w40, but does with every other oil I've run. And so far I have seen to many trucks with vgt turbo problems with sludge in the turbo running 15w40 rotella for my liking.

What about Schaffers 15w40 blend and turbos?

Only reason Im wanting 15w40 is for the towing. Its gets hot here in the summer and Im always having the AC on. Im sure Im waaaay overthinking all this but thats how I am I guess.
 

Dozerboy

Well-known member
Jun 23, 2009
4,918
497
83
TX of course
Run it once and do and oil analysis. Its one thing to over think things. It an whole nother thing to over think things using hear say over facts. IMO any of the major oils out there are fine to run, but I'm not a fan of Rotella.

No way in hell I would put Royal Purple I a turbo diesel. See it once in person and heard of a few other times of it sludging up really bad.

Sent from my SAMSUNG-SM-G900A using Tapatalk
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,729
297
83
Boise, ID, USA
I'm with mike diesel: I run good old Delo 400 and change it at 10k or so. Oil analysis always came back great, and when I tore my motor down to build it, it looked great (except the cylinder that had a glow plug go through it, which was beat to crap). Bearings were great, pistons were great, block was great (even the cylinder that got killed, amazingly).

I'm still running Delo 400 after the build, I just change it more often than on the stock motor (5k changes for now). Once it is fully broken in, I'll start increasing the change interval based on oil analysis.
 

WVRigrat05

Wound for sound
Jan 1, 2011
3,081
4
38
36
French Creek, West Virginia
When I ran Dino oil in my LLY, the turbo was full of junk, esp with rotella. I ran royal purple forever because it was free from the rig, it cleaned things right up.

I run amsoil in my LMM and change it every 3-5k, but I drive like a kid.
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,517
501
113
Central OH
Sludge in the turbo aka oil coking is from shutting it down while exhaust temps are too hot (350°+).

I'm not a real believer in synthetic oils, especially with the limited amounts that have to be synthetic for it to be labeled so.

When I worked at the cummins tech center, they ran Premium Blue 15/40 (obviously), and those engines are put through hell, with higher oil temps and coolant temps only a moron would run it to in a pickup. After a hotbox test engines would get torn down, and the only thing wrong is usually abnormal carbon in the ring lands. But that's what you get running oil at 280°F for 250hrs.

In my personal truck with 220k, I've ran Delo; Delvac; Rotella t6 and regular; Premium Blue and Amsoil one time. Only difference I've ever noticed was the smell coming from the blowby tube. Motor was still clean inside when I peeled it open to check lash. Been running Delvac for the last 2yrs, its great oil and its usually the cheapest at Rural King.
 

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