Rotella 15w40

-
If its for diesel, it has things you dont need or even want in some cases.

If it's all you have and it's a one time thing...it wont kill it.
 
If its for diesel, it has things you dont need or even want in some cases.

If it's all you have and it's a one time thing...it wont kill it.
I was just reading on a few posts about it. Looking for something to run in it permanently. What weight would be preferred?
 
I was just reading on a few posts about it. Looking for something to run in it permanently. What weight would be preferred?
What kind climate do you live in?

If its California, 20/50 or 30 covers most.
East coast, 10/30 or 30
I think Chrysler had it right with where the middle of the road was..30 wt.

You can technically run 5/20,30,40 etc...
Heat fades the psi as much as 15psi or so shown more at idle on the gauge. 20/50 was chosen as the general race weight because of it's good operating temp range protection aka viscosity sustainability from low to high rpms and film strength for momentary air pockets in the system, 'think pickup gets uncovered with g forces'

Me.. I run Schaefers superme 7000 20/50 para synthetic.
 
I live in Texas where the climate is very similar to California. I have always run 30 straight. For a while ran VR-1 Valvoline. Now started to run Brad Penn 30 and it is nice! Also bought a case of Schaeffer 30 wt. Haven't tried it yet but have heard good things about it.
 
Which Rotella? There's T3 (Dino), T4(Blended), and T5 (full synthetic).
With flat tappets, run the T3 (has zinc ZDDP additive). If you're running rollers, the blended or full syn will work just fine.
 
What kind climate do you live in?

If its California, 20/50 or 30 covers most.
East coast, 10/30 or 30
I think Chrysler had it right with where the middle of the road was..30 wt.

You can technically run 5/20,30,40 etc...
Heat fades the psi as much as 15psi or so shown more at idle on the gauge. 20/50 was chosen as the general race weight because of it's good operating temp range protection aka viscosity sustainability from low to high rpms and film strength for momentary air pockets in the system, 'think pickup gets uncovered with g forces'

Me.. I run Schaefers superme 7000 20/50 para synthetic.
Eventually I do want to run staffers. Just at the moment want to get it in and running. I live in PA so summers are anywhere from 60-90°
 
Which Rotella? There's T3 (Dino), T4(Blended), and T5 (full synthetic).
With flat tappets, run the T3 (has zinc ZDDP additive). If you're running rollers, the blended or full syn will work just fine.

A little off. T4 is dino, T5 Blended. I've run T4 15w-40 with a bottle of zinc in the hot rods for years. Also put in my mowers and T5 in my Victory bike. I'm a fan. It takes diesel abuse to 10-15,000 miles without issue. It's certainly good enough for our little motors.
 
Check the current spec sheets and oil analysis (virgin and used) that people post on the web.
Many oils including the Rotella line were revised about 5 years ago.

It depends what bearing clearances the engine has and how it's going to be used.
This ^^^^^^^^

Here's what was posted in:
Oil Viscosity vs Bearing Clearance
and discussed in posts here
Valvoline VR-1 vs. Lucas Hot Rod oil

[Below is quoted from the thread linked above. I'm not a builder and in no position to say whether they are good guidelines based on my own observations and experience, but they appear to be.

For general use, its usually better to use a multi-grade.
Whatever W portion is in front will provide better lubrication when the oil is not fully warmed up than a straight grade. One they are at operating temperature, the viscosities are about the same. That said, 40 and 50 grades tend to have better high temperature, high shear performance.]

Multi-grades.
Some recommended rod bearing oil clearances for various oil viscosities:
.0015 to .0018 for 0W20 or 5W-20
.0020 to .0024 for 5W-30 or 10W30
.0025 to .0029 for 10W-40 or 15W40
.0030 to .0040 for 15W-50 or 20W-50

For main bearings:
.0015 to .0020 for 0W20 or 5W20
.0020 to .0025 for 5W-30 or 10W30
.0026 to .0030 for 10W-40 or 15W40
.0031 to .0041 for 15W-50 or 20W-50

Single Grades
Rod bearings with
.0015 to .0018 use 20
.002 to .0024 use 30
.0025 to .0029 use 40
.0030 to .004 use 50

For main bearings:
.0015 to .002 use 20
.002 to .0025 use 30
.0026 to .003 use 40
.0031 to .0041 use 50

After break-in, depending on how it was machined, probably best to use a conventional base stock for a few thousand miles.
One current option for a conventional oil with decent Zddp levels is "Ford Super Heavyduty" which meets FORD WSS-M2C171-F1
some specs here
PETROLEUM QUALITY INSTITUTE OF AMERICA TEST PROGRAM

The higher the spring pressures, the more concerned I'd be about the ZDDP.
800 ppm is pretty good.
For a cam that's somewhat radical, I personally prefer an oil more around 1200.
 
Last edited:
I quit Rotella in my diesel trucks because there was always 'stuff' in the bottom of the white gallon jug.
 
Last edited:
I’m running T-4 15/40 in my Roadrunner, due to its high zinc count. It has 72k miles on it, and I don’t think it hurts it a bit.
 
A little off. T4 is dino, T5 Blended. I've run T4 15w-40 with a bottle of zinc in the hot rods for years. Also put in my mowers and T5 in my Victory bike. I'm a fan. It takes diesel abuse to 10-15,000 miles without issue. It's certainly good enough for our little motors.
Yep, you're right- I was just shooting from memory, which is a crapshoot at my age... :BangHead:
 
Check the current spec sheets and oil analysis (virgin and used) that people post on the web.
Many oils including the Rotella line were revised about 5 years ago.


This ^^^^^^^^

Here's what was posted in:
Oil Viscosity vs Bearing Clearance
and discussed in posts here
Valvoline VR-1 vs. Lucas Hot Rod oil

[Below is quoted from the thread linked above. I'm not a builder and in no position to say whether the are good guidelines based on my on observations and experience, but they appear to be.

For general use, its usually better to use a multi-grade.
Whatever W portion is in front will provide better lubrication when the oil is not fully warmed up than a straight grade. One they are at operating temperature, the viscosities are about the same. That said, 40 and 50 grades tend to have better high temperature, high shear performance.]

Multi-grades.
Some recommended rod bearing oil clearances for various oil viscosities:
.0015 to .0018 for 0W20 or 5W-20
.0020 to .0024 for 5W-30 or 10W30
.0025 to .0029 for 10W-40 or 15W40
.0030 to .0040 for 15W-50 or 20W-50

For main bearings:
.0015 to .0020 for 0W20 or 5W20
.0020 to .0025 for 5W-30 or 10W30
.0026 to .0030 for 10W-40 or 15W40
.0031 to .0041 for 15W-50 or 20W-50

Single Grades
Rod bearings with
.0015 to .0018 use 20
.002 to .0024 use 30
.0025 to .0029 use 40
.0030 to .004 use 50

For main bearings:
.0015 to .002 use 20
.002 to .0025 use 30
.0026 to .003 use 40
.0031 to .0041 use 50

After break-in, depending on how it was machined, probably best to use a conventional base stock for a few thousand miles.
One current option for a conventional oil with decent Zddp levels is "Ford Super Heavyduty" which meets FORD WSS-M2C171-F1
some specs here
PETROLEUM QUALITY INSTITUTE OF AMERICA TEST PROGRAM

The higher the spring pressures, the more concerned I'd be about the ZDDP.
800 ppm is pretty good.
For a cam that's somewhat radical, I personally prefer an oil more around 1200.


I agree with most of this. What I disagree with is it’s not 1985 anymore. A properly honed bore with modern rings will be ready for synthetic oil as soon as the cam is broke in. I’m all for leaving the brake in oil in longer than that. I leave it in for 700 miles or so and go straight to synthetic oil. I could change it out sooner, and probably will when I switch to roller lifters.

The other thing is modern, decent oils can run a bit looser that the above chart calls out. I’m at .0021 on the rods and .0023 on the mains and I’m going to use a 0w20 oil in it. And it gets hot here in the summer.

I also don’t use 7 bucks a quart oil either.
 
What I disagree with is it’s not 1985 anymore. A properly honed bore with modern rings will be ready for synthetic oil as soon as the cam is broke in. I’m all for leaving the brake in oil in longer than that. I leave it in for 700 miles or so and go straight to synthetic oil.
I tried to get the builder's view on that for my jeep's 360 and got a pretty vague answer. Figured it was best to assume the rings might need conventional. Stock cam, 0.30 over, just a rebuild.
 
I tried to get the builder's view on that for my jeep's 360 and got a pretty vague answer. Figured it was best to assume the rings might need conventional. Stock cam, 0.30 over, just a rebuild.


It depends a HUGE amount on the cylinder finish. If the machinist is using vitrified abrasives, it will take different techniques to get the correct finish than if he is using Diamond abrasives. And if they use a brush finish, a CBN finish or a combination of both.

What’s crazy is I’ve seen profilometer readings change a significant amount with 3 strokes of a finish brush. I’m mean a big move.

So if the machinist isn’t using a profilometer then I’d certainly start out with mineral oil and leave it in there for 500 miles. You can ***** up a set of rings right quick if the machinist isn’t careful.

I used to think I could hone a cylinder about as good as it can get. After watching a Rottler CNC hone, with a ball drive head finish a bore, I can’t even get within a country mile of that machine. Not even close. It’s that good a machine.
 
Well damn. All my machinist told me was to use an oil with high zinc. LOL

So I use that Lucas Hot Rod & Classic Car oil. 20w50 flavor for these 90 deg CA days.
 
I'm not a big fan of using diesel in gas engine. Even Shell does not recommend it.

No reason to use a 15/40 in most vehicles either.

I had a Ford van with a 351 gasser . Bought it with 105k... Sold it with 485k. Tried Citgo 10w-30...used too much and the oil temp soared. Went to Mobil1 10w-30 after the first change.

I have 30w CenPeCo for my race motor. I use a single grade for the alky motor.
 
I'm not a big fan of using diesel in gas engine. Even Shell does not recommend it.

No reason to use a 15/40 in most vehicles either.

I had a Ford van with a 351 gasser . Bought it with 105k... Sold it with 485k. Tried Citgo 10w-30...used too much and the oil temp soared. Went to Mobil1 10w-30 after the first change.

I have 30w CenPeCo for my race motor. I use a single grade for the alky motor.


not talking about using diesel in a gas engine (i tried it once, didnt work out well, long story)

we are talking about running diesel grade oil in a gasoline engine

(im sure thats what you meant too, but cant be too carefull nowadays)
 
Does anyone know if Rotella or other diesel oils still have zinc? I was told 2 or 3 yrs ago that Rotella doesn't have it anymore.True or false?
 
Does anyone know if Rotella or other diesel oils still have zinc? I was told 2 or 3 yrs ago that Rotella doesn't have it anymore.True or false?


False. Any ENGINE oil must have zinc in it. It’s the level of zinc that changes.

Again, an engine oil that is formulated for Diesel engines isn’t good for a gas burning engines. They use more detergents, different detergents and other additives that affect almost every facet the oil must meet.

You (not you particularly but anyone wanting to know) can spend a day on the web looking at a multitude of webinars and such on oils, oil formulation, lubrication, tribology and a host of other oil related topics can find this information.

We have long since passed the day when engine oils are mass market junk. We have a multitude of quality oils to choose from, to the point that there is no reason to run on the shelf oil.

I’m still baffled that guys will spend money like water on their engines and then throw Walmart or some other cheap assed oil at it.

Hopefully by the end of the year I’ll be able to test oils. The data will be mine, so I’ll be able to publish the results. It should open some eyes as to how garbage some of these oils really are.
 
-
Back
Top