:eek: I stumbled on this forum from a GM Engineer who was in on the making/testing of the GM OIL LIFE MONITOR.

VERY,VERY Interesting.:exactly:

His Sign on is Jestal......

http://p083.ezboard.com/ffjr1300ownersassociationfrm12.showMessage?topicID =536.topic

:eek: I stumbled on this forum from a GM Engineer who was in on the making/testing of the GM OIL LIFE MONITOR.

VERY,VERY Interesting.:exactly:

His Sign on is Jestal......

http://p083.ezboard.com/ffjr1300ownersassociationfrm12.showMessage?topicID =536.topicMiDmax, Thanks for posting this excellant thread. :exactly: I've been reading it for an hour and plan to read the rest later. This is the most informative oil thread I have EVER read and I'm sure it will be very usefull for all who read it. Jestal is definately an epert on engine lubrication. :bow:

Thanks for sharing this great thread.:thumb:

interesting thanks.

Yeah, there's some good info in that thread.

I'd like to hear Greg Landuyt's opinion on the matter...

Awesome post. There are allot of interesting things to think about there. I know so many guys who think oil changes every 3k miles is a must. But some of the basic points that are brought up by this thread are over looked by most people today. Even the simple point that there are no longer so many tasks for the oil to perform (i.e. distributor gear etc). Thanks for the informative find.

Good read -- although I drew the opposite conclusion -- synthetic oil is a necessity for a bombed turbo diesel due to extreme engine temperatures under load.

Think we could invite him over here?

Actually, there is already a thread in progress on this subject in the GM 2500HD 3500 topic area, called "Comments for a GM Engineer". Here is the link:

http://dieselplace.com/forum/showthread.php?t=30090&page=1&pp=10

And if you want to read more, the TDR also has a thread going on this. Here is the link:

http://www.turbodieselregister.com/forums/showthread.php?t=127780

I wouldn't be surprised if the Ford site (DieselStop) also has a thread, but there is not enough time in the day to follow them all.

On Edit: BobistheOilGuy.Com also has a "long" thread going on this topic:

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=010447#000000

I there's probably a lot of truth to what he's saying from what I've read so far. I think I'm going to stick with the Delvac 5-40W I'm running now for extra protection during really cold starts and possible high operating temps with the performance mods.

But, I do not feel that this oil or any synthetic for that matter is as far superior to dino oil as I once thought. I still maintain that some of these synthetics are excellent products, as Jestal noted.

Regardless, I'm going to let used oil analysis help me determine drain intervals--that seems like the smart solution to me.

Here are some quotes I feel are key points made by Jestal:

"Yea, I agree, oil in turbocharged applications is a good candidate for synthetic."

"I use Delvac 15W40 in my FJR and most everything else around the house."

"Class 8 , over-the-road diesels can go for long distances without oil changes simply because they carry a LOT of oil onboard."

" BTW...you don't get any ZDP in any of the aftermarket snakeoil additives."



I would definitely like to have this guy as a member here. How can we invite him over here?

:confused: If the motor is showing 200+ degrees (operating temp) by which our coolant is maintaining, I expect the extreme temps are being expelled as in EGT's. Not the internal motor temp. Does this sound incorrect?

I wish I knew 1/2 as much as some in the forums......
I sure appreciate all they do for us.........:ro)

Well I'm not sure--coolant temp and oil temp are two different things. While they are obviously closely related, I'd be willing to bet that your oil jumps way up in temp when pulling hard in really hot weather even if the engine fan kicks in and the coolant temp stays within reason.

This is why I'm planning on adding an oil temp gauge--I'm a gauge freak, and I think this truck and extra gauges might be able to teach me some things about engines in general, especially turbo diesels.

Modern turbo diesels use oil sprayers to cool the piston. If temperature is an issue with dino oils, I'd say syn would have an advantage. While the average oil temp is not much different from a gasser, the peak temp the oil is exposed to is much higher.

This is soooooooo interesting............

The biggest thing I got out of it is, synthetic is better when exposed to extreme temps but it can be wrecked by having a bunch of sh!t put in it, and using up wear additives, just like can happen to dino.

Anyone know how hot the oil is coming out of our turbo center section?

I don't want to think about how hot that oil is. If the gas going though that turbo is in the neighboorhood of 1200 degrees, the turbo, and the oil inside that turbo has got to be atleast 300 degrees.
I know from my experience with oval track race cars, the oil inside that pan can get well above 350 degrees. :weld: The races we run are no more than a half an hour, but that is with the engine running between 4500 and 7200 RPM's, race fuel, and 12 to 1 or better compression. So there is a LOT of heat generated inside that motor. If we keep the water temperature between 210 and 230 we consider ourselves lucky.

I totally understand the point they are trying to make about the friction modifyers. But if the oil breaks down so bad, shouldn't you see a decrease in mileage? Also, how come since installing sythetic in my D-Max, it runs cooler? Does that mean the oil is carying away more heat, not likely, the decrease in temperature has to be because of a decrease in friction inside the motor. Friction is the enmy of all engines. Any time you decrease friction the motor will last longer and make more power.

the decrease in temperature has to be because of a decrease in friction inside the motor. Friction is the enmy of all engines. Any time you decrease friction the motor will last longer and make more power.That sounds like a good explanation -- Friction causes heat...

no i don't think that is it at all. idk how you saw a change in operating temperature. i would LOVE to see that under STP (standard temperature and pressure of the motor)

it has to do with the properties of the oil that allow it so withstand the extra heat. i doubt that it is just because sythetic is sliperier that is allows it to take more heat.

IMO i think you have extemely over simplified what is going on.

He didn't say anything about the synthetic being slippier allowing it to take more heat - he said it reduces friction, thereby reducing friction-created heat. Less heat created = lower engine temps.

So.........:confused: Do we go Up? Down? Left? Right?

Is the glass half full or half empty.

WHAT IS THE WAY TO GO?????:help:

My oil analysis dont lie.... Schaeffers in my truck

I don't normally weigh in on these discussions but I guess I will give my opinion. He is just one guy that happens to be and engineer. Ask George Morrison what he thinks about synthetics and it will be the the other way.

The oil monitor system can in no way tell you what life is left in the oil. I have had to reset mine twice in 16K miles and my oil analysis is saying the oil has plenty of life left in it. Oil analysis do not lie.

Also notice the only good thing he say about synthetics is it will take the heat, nothing about stability.

Also synthetics are way more stable than dino and the additive packages used are better than in Dino because of it. The additive package is what keeps all the stuff under control and helps keep it in suspension.

Synthetics also help the rings seal better which leads to less combustion by products From getting into the oil which again leads to a longer life.

I could go on but way? It is just ones mans opinion just like mine. He is not the last word nor am I. I don't care what synthetic is used because they are all better than dino. Also here seems to want to slam on Amsoil but if they were so bad and scamming everyone the FTC would have done something about it over 30 years ago. I will go with the majority and technology when it comes to synthetics.

Way change your oil if the oil is still good to go and the filters are kept changed. Fleets and construction companies have been doing this for years and its nothing new. We are just doing it on a scaled down version.
Greg

He mentions that synthetics do nothing to allow for extended drain intervals. I think Mercedes would beg to differ. They had a lot of motor problems when consumers followed their oil change intervals (which are based off the use of synthetics) using mineral-based oils.

Well for the benefit of my Truck .......... I'm going to follow dmaxalliTech's tracks and go with


:exactly: Schaeffer Motor Oil :ro)

Copied my response from the 2500/3500 thread, same subject:

OK, finally finished reading that thread. I give the guy his due, he has enough confidence in his technical ability and expertise to air it out in a forum much like ours, stood his ground to. While I don't agree with everything he said he did bring some interesting points up. http://www.dieselplace.com/forum/images/smilies/smile.gif

I had heard that the initial oil in our trucks had some special properties and that we should run them for a while. We've had this discussion on the forum several times about when to change the oil. I'm glad I left the original in for 1k miles, it appears I likely made good use of the ZDP rich environment. His points about the initial break-in and metal components within the first 20-30 miles was enlightening as well. http://www.dieselplace.com/forum/images/smilies/wink.gif

The only question I had was "Doesn't an engine take on different operating characteristics after you strap a truck and tranny onto it and work it good? I would suspect the answer is a resounding yes! http://www.dieselplace.com/forum/images/smilies/biggrin.gif

His argument about Mobil 1's "extended service" not being an extended service brought the question to mind: Is Mobil 1 going to advise customers to follow the manufacturers oil change schedule during the warranty period, or find themselves in a liability situation should something break? :rolleyes: Smart thinking in my book. Also, why does Mobil 1 advise to follow the "Oil Life Monitor" change intervals? The PCM tracks all this stuff, if it doesn't show you changed the oil and you have a problem the manufacturer can contend that you didn't follow proper maintenance procedures. Again, Mobil 1 CYA! http://www.dieselplace.com/forum/images/smilies/hihi.gif

I didn't realize that oil filters can be bypassed at very high flow rates. I thought he gave good advice during initial breakin not to run high RPM's to avoid metal shavings going unfiltered into the bearings! Thank you GM Engineer man! http://www.dieselplace.com/forum/images/smilies/confused.gif

OEM filters are looking much better to me! http://www.dieselplace.com/forum/images/smilies/rolleyes.gif Good intel on this post. Concensus seems to be that guys/gals that run performance mods, push their trucks to the upper limits (RPM's and heat), or tow heavy with their trucks might be better off to stick with synthetics since they tend to offer better protection at high temps/stress conditions and not break down as fast as dyno oil under these conditions. :confused:

There is a guy on the bobstheoilguy site, can't remember his name, that I would love see go head-to-head with the GM engineer guy. We could gain a lot of intel from them both. Later. JJ http://www.dieselplace.com/forum/images/smilies/smile.gif
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