Not another synthetic oil question...

[vonTrapp]

quote:

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Originally posted by 4x4man:
After all my Exhaust temps coming out the manifold have been up to 1300 degrees pulling grades in Colorado

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Sorry, but I had to point something out

1300 Deg on your pyro??? That seems DANGEROUSLY high! Have you done some mods to that Duramax (like upping the fuel delivery)?

If you are pulling grades for extended periods at that temperature on a stock engine, I would think you're going to start hurting components (Aluminum melts right around 1250 or so I think). Synthetic oil wouldn't matter if your pistons or turbo start cooking!

Could be towing in too high of gear...try raising the RPM by downshifting a gear, the added air flow through the engine will help cool it a bit.

Okay, you can commence the group beatings now for going off topic.

 

[4x4man]

Sorry for not keeping up on this in the past few days. Yes I have seen 1300-1400 degrees pre turbo pulling 7% grades with our fifth wheel both with and without a power box. The power box I run is an Edge Juice box, set on the 40hp level when towing. I have mounted my EGT probe in the passenger side exhaust manifold, so it measures the temps right out of the combustion chamber, then temps I am most concerned with.

I tried a 4" exhaust system and while I did see about a 200 degree drop in temperatures, it was just too loud for our tastes and I put the stock exhaust back on. But for now, I just back off the throttle and the temps lower, I do not sustain those temps for very long and slow down or downshift to lower the temps.

My main concern was making sure I am using the best oil to make sure my investment is protected under these situations. I don't mind paying extra money for synthetic oil, but I want to make sure I am getting what I am paying for. If I will never see the extremes that synthetic is made for both heat and cold, then I would rather spend the money else where. Then again if Delvac 1 won't hold up in these situations, then maybe I need to look at something else that will.

Gosh now I don't know what to do again!!

 

[toyvwbenz]

Use used oil analysis to help find the best oil for your conditions.

 

[vonTrapp]

For what it's worth:

Our Dodge is a 98 Cummins 3500 4x4 Chassis with a NV4500HD transmission behind it. We regularly load very heavy weights into the 12 foot dump body, and run the truck 12 -14 hours per day all year.

She's worked HARD all her life (ALL HER LIFE, not just pulling a 5er every 10th weekend) and has run 380,000km on bulk 15W40 diesel oil, mostly Canadian Tire's house brand and sometimes Walmart's house brand (note: someone for goodness sake respond to my other thread on "Cdn Tire Rotella" LOL...it's quiet as a graveyard there!)

With changes every 5000km (incl filters which are ALWAYS Fleetguard) she's still going strong, even with all the dust and crap we operate in. On a severity scale of 1-10, we're probably an 8 to 8.5...we are off road 10% of the time, but we're ALWAYS hauling a waste container or a load of garbage.

Now, I have not done a used oil analysis, because the motor and pump run awesome, but the rest of the truck is tiring out a bit (eg replaced all brakes, rotors, complete rear end rebuild, driveshafts, yokes, u joints etc).

But at 380,000 on the odometer on conventional oil (and mostly house brand CI-4 oil at $29.99 per 20L pail) well, I personally do not see the cost advantage of using synthetics in the motor. I would next time use synthetics in the running gear, however.

But I just can't justify huge bucks to run synthetic motor oil when the rest of the truck is going to wear out. Cost / Benefit wise, it isn't there IMHO.

These trucks (incl the Powerstrokes / Duramax's) are engineered to obtain a certain mean or average lifespan. Sure, there's always someone's buddy's friend's wife's sister-in-law's dog's trainer whose got 1,000,000 on the odometer, but it's an anomoly...most people I would say are likely to get 300-500K km before they trade in, or before truck operating costs / repairs start justifying a new truck purchase or lease..

These aren't 1,000,000 mile hi-way rigs we're talking about; they're commercial cab and chassis or pickup trucks we're talking about. The components are not engineered or designed for a lifespan that long, although some do make it. But there are so many variables at work to get that mileage (usage, driving patterns, loads, roads etc). I'm just trying to play devil's advocate here, and present another viewpoint.

Anyways, I'll get off my soapbox here. Really, I think it's an individual matter of preference and peace of mind whether to use Dinosaur Oil or Synthetics.

ps Uhhh...After reading your forums, I guess running 80W140 in a Cummins to quiet it down is not a good idea?

Relax...I'm kidding

[ April 11, 2004, 10:47 PM: Message edited by: vonTrapp ]

 

[Eiron]

vonTrapp,

All good points (except for the hugh volume of oil you're going thru

), but 4x4man's situation is different from what you're outlining. He's already doing 5,000 mile OCIs on dino, & his OLM is telling him to take it farther than that. Since the OLM considers his driving conditions, as well as a host of other factors, it doesn't sound like he's putting his truck thru anything like you are. Right? (Otherwise, the OLM would tell him to change it as often as you do!)

GM's OLM has proven itself to be reliable (via used oil analysis listed on this site), but he really just wants to know that he's got some extra margin w/o wasting more time, money & resources. If GM's taken the time & trouble to program an OLM specifically for his vehicle using dino, then why shouldn't he take full advantage of it with the improved durability & protection of syn? That seems a lot smarter than excessive & unnecessary changes based on tradition, doesn't it?

 

[vonTrapp]

Eiron:

An excellent response...all valid points.

Would the OLM change out be THAT much different on synthetics? Also curious if his warranty would / could be voided through extended drail intervals. Food for thought there...

Oh...about the 5000km thing...I'm sure we could go to 7000-8000km per change, but changing at 5000km is more for my own peace of mind (or piece of mind, depending on one's point of view

). We deal with unreal amounts of dust, plus the truck tends to idle / fast idle alot...get a little paranoid about diesel fuel washing into the oilpan. As well, running syn in the motor at this mileage might open up a can of worms (synthetic is VERY good at cleaning engines...maybe too good!)

I admit it may be a little old school, but I'm going to keep watching the extended drain interval issue before we decide what to do.

ps The Dodge will soon be replaced, likely with a 2003 F550 6.0 PowerStroke...THAT unit will run synthetics in the driveline...still deciding on whether to syn the motor. We'll see...

 

[Eiron]

vonTrapp,

No, the OLM in 4x4man's Duramax would not change his interval based on using syn. The GM OLMs are pre-programmed assuming the use of whatever type of oil the vehicle comes with. In the case of the Corvette & Saab (& maybe Opel?) models, that means synthetic. For everything else (I think?) that means dino. (Of course, for diesels I'm sure they're considering dino HDMOs rather than dino PCMOs.)

Since he's only going half as long as the OLM is measuring, I'm suggesting he use a syn HDMO & go as long as his dino-programmed OLM is saying. As long as he follows the OLM for his OCIs, he's staying well within his warranty requirements. Using syn simply guarantees he's not getting anywhere near the EOL for his HDMO. (If you're not confused yet, ask me again & I'll see if I can get you there!

)

I understand why you're doing what you're doing, even if I think you too would get better protection by going twice as long on syn. (And if they're all HDMOs meeting the necessary specs, I'd think the dinos should already be keeping the engine nearly as clean as syn will.) For you & me (that is, those OOW folks), that piece of mind which generates peace of mind keeps telling me, "better protection over longer intervals ..." Then another piece says, "Hey! Are we still talking about motor oil??"

(I know I had a piece of my mind when I came in here. If I could only find it now ...)

 

[vonTrapp]

Sorry to HiJack the thread...

yet again LOL.

The Dodge is getting replaced fairly soon. We're looking very hard at an Isuzu 5500.

Going to find out about running synthetics in the running gear...will post a message sometime soon in the proper forum for this issue.

[ April 15, 2004, 03:44 AM: Message edited by: vonTrapp ]