Wal-Mart Rotella 10W-30 Shelf Tag

[JasonA]

It's a 4-quart jug, so it makes for a nice even $20 oil change (plus filter) with an extra quart or two for top-off during the OCI.

[Cadillac Jim]

I would hope that the price is similar for 5W-30. Thanks.

[JasonA]

Unfortunately, Rotella is only available in a few weights. 5W-40, 10W-30, and 15W-40. They also have a few straight weights (like HD30).

www.rotella.com has all their product offerings.

[wiz6728]

DO ANY OF U ACTUALLY USE 5W30 IN YOUR CADILLAC? THAT THIN OIL SCARES ME ESPECIALLY IN A BIG MOTOR

[JimD]

Starting in 2000, Northstars were factory filled with 5W-30.

[BodybyFisher]

Starting in 2000, Northstars were factory filled with 5W-30.

Keep in mind that in 2000 the NS came with roller CAMs, the 95 has rubbing surfaces

[Ranger]

DO ANY OF U ACTUALLY USE 5W30 IN YOUR CADILLAC? THAT THIN OIL SCARES ME ESPECIALLY IN A BIG MOTOR

Not me. I still use 10W30.

[JasonA]

DO ANY OF U ACTUALLY USE 5W30 IN YOUR CADILLAC? THAT THIN OIL SCARES ME ESPECIALLY IN A BIG MOTOR

Why not? It's what Cadillac recommends (for a 2000+ engine). Many engines use 5W-20 now.

It used to be that viscosity was the key to engine protection. A thin oil didn't protect as well. But now that oil chemistry has evolved so, the additive packages perform the same metal-to-metal protection that viscosity once did, and now the thicker oils just waste fuel (economy).

As you know, a 5W-30 and a 10W-30 is essentially the same at operating temperature. The difference is the cold pumpability. If you live anywhere where it gets even remotely cold, you'd be doing your engine a disservice by using 10W-30 oil. There's no such thing as too thin an oil on a cold startup. Remember that. A 5W-30's cold viscosity is much lower (thinner) than a 10W-30 oil.

The Cadillac spec for a 2000+ engine is 5W-30 "recommended", 10W-30 "acceptable" (above 0*F I believe...or 32*F, I can't remember which).

I currently have the Rotella 10W-30 in my 2001, but will try Pennzoil Platinum 10W-30. It's cold viscosity is about the same as a 5W-30 conventional oil, and its price compares favorably with the conventional oil I'd have bought anyway (Pennzoil yellow bottle). I know I'm wasting fuel with the relatively thick Rotella I have in it now.

[Patrick7997]

15w40 Rotella hasn't cost me any fuel mileage at all....

I may print out that picture when I get home, and try to show that to the Wal-Mart people....

I've questioned them repeatedly about this product, and they all say the same thing: "We don't have it. There's nothing in the back room. Everything we have is out on those shelves."

I'm also intrigued by that zddplus website someone posted. Kinda expensive, but it might be another way to go....

[Cadillac Jim]

My 1990 Quad 4 HO specified 5W-30, and it had direct camshaft-to-lifter contact. I had it for 7 years and shifted at about 7000 RPM occasionally for all that time and never had a problem with the motor, except a PCM going south in 1992 and an obscure dealer-fixed-on-warranty driveability issue in 1994. When I traded it for my Cadillac in 1997 with 85,000 miles it ran as good as the day I bought it and had the original cams, although the cam chain tensioner was changed in 1994. My 1997 Northstar specified 10W-30 which I ran for years. In about 2001, my Cadillac dealer started recommending 5W-30 for my car and I've been using it since.

I run synthetic oil, which actually has a higher viscosity at 40 C and 100 C than 10W-30 of the same manufacturer (Mobil 1) but less variation in viscosity over temperature. I disagree with BodybyFisher about direct action cams needing 10W-30, in part because of my long experience with the Quad 4 HO running the factory-recommended 5W-30 with its 6800 RPM redline.

Whatever you do, honor your owner's manual about grade and viscosity of oil. My 1997 says to use 10W-30 for lowest daily temperatures of 0 F and above, and 5W-30 for lowest temperatures below 60 F (1997 FSM, page 0B-4, figure 2 at bottom left). Other notes on the figure, which should also be in your owner's manual:

• 10W-30 is the preferred grade for temperatures over 0 F.
• Do not use SAE 20W-50 or any other grade oil not recommended.
• For best fuel economy and cold starting, select the lowest SAE viscosity grade oil for the expected temperature range.

Since the low temperature for the day is never over 60 F where I live, 5W-30 is OK year-round in my climate according to my FSM. I use synthetic oil, which isn't mentioned.

I had a friend with a 2002 Blazer with the 325 cid Chevrolet V8. He used it primarily to tow an Airstream for touring. His owner's manual recommended 10W-30 dino oil for most driving, but that the owner consider 5W-30 synthetic oil for temperatures below 0 F, and consider 0W-30 synthetic for temperatures much below that.

[JasonA]

...I run [5W-30] synthetic oil, which actually has a higher viscosity at 40 C and 100 C than 10W-30 of the same manufacturer (Mobil 1)...

I think this illustrates that there isn't THAT great of a difference between 5W-30 and 10W-30 sometimes. As Jim said, with Mobil 1, it's even backwards. Indeed, by the kinematic viscosity numbers, the 5W-30 is thicker than the 10W-30 (at BOTH measured temperatures). For MOST oils, the 5W-30 is quite a bit thinner than the 10W-30 at 40*C, and about the same (in terms of viscosity) at 100*C.

In general, I would prefer the 10W-30 over the 5W-30 due to the use of fewer Viscosity Index Improvers. If you examine Noack Volatility data published by Pennzoil, all three of their main-line oils (conventional in the yellow bottle, high mileage in the copper bottle, and synthetic in the silver bottle) show greatly reduced volatility in the 10W-30 grade vs. the 5W-30 grade. The conventional 10W-30 is 26% less volatile than 5W-30, the high mileage 16% less, and the synthetic 23% less.

I personally just bought some Pennzoil Platinum (synthetic) in the 10W-30 grade because it's already formulated pretty thin. For example, its kinematic viscosity at 40*C is LOWER (thinner) than all of these 5W-30 oils: Mobil 1, Pennzoil conventional, Pennzoil High Mileage, Valvoline conventional, Valvoline MaxLife. The viscosity at 100*C is also lower (thinner) than all of them as well. So those "thin" 5W-30 oils are actually THICKER than the 10W-30 that I'm about to pour in. You can't JUST look at the nominal oil weight grades. There's a lot of variation allowed within those grade specifications. And not only that, but viscosity in itself isn't really a good indicator of an oil's protection performance anyway, in this day in age.

[Cadillac Jim]

All very good points. Here is what I go by:

• My 1997 owner's manual and FSM say to use 5W-30 or 10W-30 and doesn't mention synthetic oils. I have seen later model GM owner's manuals refer to synthetic oils for colder temperatures or heavier engine use such as towing, and GM ships Corvettes with Mobil 1.
• The two weights in multigrade oil refer to viscosity at 40 C (104 F) and 100 C (212 F), and give an indication of how much variation in viscosity you will see over temperature. I'm interested in thinner oil at 0 C (32 F) and thicker oil at 150 C (300 F). 5W-30 will perform better over this temperature range than 10W-30.
• Synthetic oils generally have lower volatility than dino oils for the same grade.
• Most importantly, I notice a performance difference with synthetic 5W-30 over dino 10W-30.

There is a lot of data and there are theories, but between the FSM and a slight but definite performance difference, I am staying with 5W-30.

[Ranger]

I have had 10W30 in my engines and started them at -20F. Never a problem. That is what GM recommended before there was a 5W30. I once asked the Guru about it and without actually coming out and saying it, he inferd that GM went to 5W30 to satisfy CAFE. He led me to believe that if left to their own choices, they would still recommend 10W30. That is what I got out of his response and why I sill use 10W30.

[JasonA]

Again, there's no such thing as too thin of an oil on start-up. We could all be using 0W-30 very safely. And it'd provide even better lubrication during a cold start.

Pressure is inversely related to flow. Higher pressure equals lower flow. Pressure does not lubricate -- FLOW lubricates. You want as much oil FLOW as possible.

10W-30 oil and 0W-30 oil are essentially the same viscosity when hot. Let's just say 10 to pick a number (as most XW-30 oils are around 10-11 at operating temperture). Don't look at the numbers on the oil bottle. Think in terms of actual viscosities. So 10W-30 and 0W-30 are both at 10 when you turn the car off at night. Overnight, both oils will thicken as the temperature drops. That's just how oils work. The next morning, the 10W-30 oil has thickened to 110, and the 0W-30 has thickened to 60. Both oils are still too thick for what the engine really wants (10). But you'd rather work your way down from 60 than from 110.

There is no such thing as an oil that's too thin at start-up -- especially cold starts. 10W-30 will crank and run at -20F. 0W-30 will protect MUCH better at -20F. The notion that 5W-30 was spec'd for CAFE reasons may be partly true...but who cares? It's also going to protect your engine MUCH better during cold starts -- especially those far below freezing. That 10W-30 is THICK at -20F. The 0W-30 will still be relatively thin. Which do you REALLY want to have in your engine?

I just bought 10W-30 oil for my 2001 because it never even gets below freezing in my garage overnight, even in the "dead of winter" in North Carolina. That said, I still could have benefitted from 5W-30 every day vs. 10W-30.

[KHE]

Again, there's no such thing as too thin of an oil on start-up. We could all be using 0W-30 very safely. And it'd provide even better lubrication during a cold start.

Pressure is inversely related to flow. Higher pressure equals lower flow. 10W-30 oil and 0W-30 oil are essentially the same viscosity when hot. Let's just say 10 to pick a number (as most XW-30 oils are around 10-11 at operating temperture). Don't look at the numbers on the oil bottle. Think in terms of actual viscosities. So 10W-30 and 0W-30 are both at 10 when you turn the car off at night. Overnight, both oils will thicken as the temperature drops. That's just how oils work. The next morning, the 10W-30 oil has thickened to 70, and the 0W-30 has thickened to 50. Both oils are still too thick for what the engine really wants (10). But you'd rather work your way down from 50 than from 70.

There is no such thing as an oil that's too thin at start-up -- especially cold starts. 10W-30 will crank fine at -20F. 0W-30 will protect MUCH better at -20F. The notion that 5W-30 was spec'd for CAFE reasons may be partly true...but who cares? It's also going to protect your engine MUCH better during cold starts -- especially those far below freezing. That 10W-30 is THICK at -20F. The 0W-30 will still be relatively thin. Which do you REALLY want to have in your engine?

One thing that people forget is that a thicker oil will have higher film strength and therefore more oil will stay on the bearings during shutdown. That will protect the engine on restart. That is often overlooked because people are concerned about cranking speed.

[JasonA]

One thing that people forget is that a thicker oil will have higher film strength and therefore more oil will stay on the bearings during shutdown. That will protect the engine on restart. That is often overlooked because people are concerned about cranking speed.

0W-30 and 10W-30 oils have the SAME viscosity when warm. When cool, both oils thicken, one just less so than the other. I think a lot of people mis-interpret the 'W' weight index (I'm not saying you are). A '0' is thinner than a '10', but we have to remember that at the measured temperature (which is actually far from cold, 40*C), both lubricants are MUCH thicker than they are at 100*C.

Cranking speed is very relevant. If your cranking speed has been reduced simply because of the viscosity of the oil (honey), there's a problem. Taken to the extreme, let's just use a straight 30 oil. It'll have a MUCH higher film strength.

Oil technology (as we know) has advanced dramatically in the past few decades. Viscosity no longer equals protection. Additive packages are much more complex than they used to be. A lot of people run 5W-20 oils with BETTER UOAs than they had with 5W-30 or 10W-30. Thinner oils are providing better protection. Just as we "know" that oils are better today such that we can safely follow the GMOLM for 10,000 mile OCIs, we oughta "know" that as oil chemistry improves such that "thinner" oil provides as-good-or-better engine protection, GM is keeping current on their oil specifications and specifying the best oil for the job.

[JasonA]

A few good set of articles outlining viscosity can be found here:

http://63.240.161.99/motoroil/

It's written by a very frequent poster on BITOG. It seems to very much follow the evidence we see in the field (UOAs with different viscosity grades, etc).