For three times the price as Rotella T 15w40 is it REALLY that much better? My engine quited down and runs loads smoother than it did with the stock oil in it, and I'm running the Rotella...seems to me that it is doing just a fine and dandy job...why pay three times the price, I say?

Derek

 

I say, to each his own.......

 

My statement wasn't mean to criticize, so I hope that you don't feel that way...I have never seen a breakdown of the two oils side by side, such as viscosity tests, overall lubrication performance and how well each breaks down under high heat...my only question was is RP 3x as good as Rotella T? If so, I may make the switch...

Derek

 

I seriously doubt that syn is 3 times better than petro if you change frequently. The two biggest reasons I use it is for extended service and the heat stability. From what I've read, I could probably get 15k out of petro oil with the bypass but I'm thinking it would be safer to run that long with syn. I'll probably stay with the 7000 cuz low ambient isn't a problem where I'm at. Craig

 

I'm using RP 15 40, It's expensive but relative to the cost of a $40,000 truck it's pretty small and I've only heard good things about it.

 

I'm not bad mouthing RP, but you might want to so a seach on Bob is the Oil Guy and look in the UOA sections. RP hasn't been that good of a performer. It's proven to be poor in shear stability and TBN retention. The best way to tell how it works in your engine is to take a sample and send it in for analysis.

Please don't take this as if I'm slamming your choice of oil because I'm not, I was just informing you of past UOA's on RP and its' performance.

Here's a link to Bob is the Oil Guy....just scroll down to the Gas Engine UOA & Diesel Engine UOA sections. Best of luck

 

How much does analysis cost and who do you send it to normally?

Also, where in the heck is a good place to check on pricing for Schaeffers 9000?

 

The 7000 actually uses a Group II+ and PAO basestock, and you are correct on the 9000 as far as base goes.

In my experience of using both oils, the 9000 obviously has better cold flow properties, and my oil consumption is lower with it as well.

Considering 7000 is like 70-80% conv/20-30% PAO, and 9000 is all "synthetic", and there is only a couple/few bucks a gallon difference when buying it in cases, I just go with the 9000 and keep it simple. It is a great oil.

Royal Purple, it is widely believed, uses GIII in their synthetic oils. I think it is a good oil, but not for what they want for it. I bought a 93 Ford 7.3 IDI on it a few years ago as a farm truck that had 280K on it with Royal Purple 15w-40and Amsoil bypass. Still runs like a top and uses no oil at all. I use Schaeffer's in it now tho.

 

You are correct. I must have been typing too fast above and not thinking at the same speed

 

The following is from Martin Williamson's (Mr. Williamson is a Noria representative) comments on an automotive forum's FAQs - Noria is an international lubrication consultancy firm:
Rusty

 

Was the consulting firm hired by Royal Purple to do the study?

What proves that RP has a purer base stock and are less susceptible to shearing than other oils with equal base stocks?

Mr. Williamson oughta take a look at the Used Oil Analysis section of Bob is the Oil Guy and look at real world analysis of the Royal Purple oils. I see an oil with an inflated price tag, that has poor TBN retention, and shears badly in engines that have past track records of being easy on oil. UOA's don't lie.

 

No, Noria is an independent lubrication consulting firm.

My point is that you can find support on the Internet for any position one might wish to take. I run Mobil 1 in my wife's Durango, Royal Purple in my Acura 3.2TL-S and Delo 400 in my Ram. All have given excellent service.

Rusty

 

I'd like to know more about shearing. Is shearing the reason an engine will use more oil after many 1000 miles of extended service than it did from the start? How do you tell from the UOA if that is happening? I started ext. service with my 97. During beak-in, I used petro oil and changed every ~3000 miles and it would only use about a cup of oil in that time. I was leary of syn engine oils at that time and there was a guy on the TDR who bragged up Lubrication Engineers oil saying it was as good as any syn, in ext. service so I tried it for a couple of ext. intervals. After about 7k miles the oil consumption would start going up and by about 15k it was using 1 qt. to about 2k miles. Then I'd change it and be fine til about 7k again and the cycle repeated itself. Also TBN would go low with the LE. Then I tried RP and it would go about 10k miles before consumption would go up and it degraded much slower than the LE. My UOAs always looked very good and I went 25k on the RP, one interval. The TBN was always right up there. But nobody could ever tell me why the consumption always goes up at a certain point and continues going up, then all is good again right after a change. Is that a shearing problem? That's one reason why I'm trying the Schaeffers 7000. BTW, I gave all the 97 UOAs to the guy who bought the truck so I can't see them again but I could swear my wear metals were lower than 95% of the Schaeffer UOAs on Bobs UOA forum. I'd go back to RP in a flash! Craig