Oh NO, not another oil discussion...

OK for the record, I know that there has been plenty written about this. I'm not looking to start any wars. I just have an honest question, and would like opinions.

I changed all the oils in my truck to synthetic about 10K ago. My intention was to do all the drive train with a particular brand of oil that we could call say brand 'A'. In the process there was some miscommunication with a couple of mutual friends. At any rate, in this process I wound up with not only drive line oils, but 5 gallons of brand 'A'.


The dealer of brand 'A' motor oil claims that he has 20K miles on this oil in his truck and it is fine. I'm at 10K, and my DIC is about to tell me it is time to change the oil. I don't have access to someplace for oil analysis. If I do, I don't know it.

I know there is at least one dealer on this forum, and I believe many using this oil. For you these questions come to mind:

after this 10K how often does one 'need' to do an analysis?
Is there some 'rule of thumb' or idea of approximately how many miles I can go before I reach say critical time to change?

I've towed heavy maybe 300 miles on this change. Other than that, it has all been local driving to and from work.

No wars please, I'm just seeking a consensus. I'm not bashing any brands either, just looking for honest info.

Brand "A" offers an oil analysis kit. Less than $20, postage paid. Visit his site (TDP supporter, www.lubricationspecialist.com) and order one, or two, or....The analysis is as good or better than Blackstone Labs or other popular testers, and they are fast. They will even call you (as opposed to waiting for the mail/email) if any part of your test is alarming.

All that said, I can't recommend running your oil past 10K, even for DD'ing, without an analysis. Once you develop a trend, you may, but you need a baseline and periodic tests. Bypass filtering is a better option if you intend to get every mile out of the oil, but you still need to test. I use "Brand A" for 10K with mostly DD'ing, and change at 5K of towing. I quit testing a long time ago, as my tests were very consistent. I will still test on ocasion, just to confirm my trend. I could probably double the miles, but just don't feel right about it.

This is what I was looking for. I'll check on the kits right away. I wanted more 'real life' experiences. I knew I should get more than 10k, but how much more I wasn't sure.

at what point is it ok to go synthetic, i've got an 06 with almost 25,000 mi. afe dry filter,dealer maintained.find the truck fascinating,don't know much about diesels,yet.my previous truck was 83 k-20 w/845,000mi,chevrolet is all i've ever owned.by the way 14.5 mpg is the best ,i've gotten,i'm not a nextel cup type driver,what am i doing wrong?still beats the 10 mpg i was getting before.i've owned the 06 since new. thanks for any info.chevrolet1

25K is well past what is OK mileage for switching. The old school thought was anywhere from 10K to 50K. Nowadays, engines are built much different, the alloys are more refined, and tolerances much closer. An actual "break in" may never be reached by the old standards. It isn't uncommon to find a modern engine with 200K+ miles, with the cylinder cross-hatch still visible, and little or no ridge. Many vehicles now come with synthetic as a factory fill (Corvette, for example). Some of them do not bench run (dyno) the engines before install, so they get no break in at all.

I switched at 10K. I have less than 20k on it now. First, I have gone round and round on what is best for the truck. I don't know if it was safe to switch that early. For every one that says don't do it 'til 30k you'll hear another that says do it and drive it like you stole it.

Nobody at the dealer had any different advice, so I switched early. I doubt seriously there will be any serious reprecussions. I also doubt seriously that I will have this truck for 250k. I am already dead set on getting a C4500 or 5500 chassis for pulling.

I care about the long range life of the engine, don't get me wrong. I just really can't find any definitive answers one way or the other.

Just my $.34 (adjusted for inflation)

The reason to change oil (in a diesel) is that the additive package becomes depleted by neutralizing contaminants; the main contaminant is sulfur. LSD and ULSD should lower the depletion rate of the additive package, but I've not yet seen any reports about the degree of improvement. Synthetic oils don't really provide enough benefit to outweigh the costs (IMHO) until more is known about the effects of ULSD.

As for me, my motorhome's AMG engine gets RotellaT 15/W40 at 3K intervals (longer - to 4K if I'm on a long road trip). My Ford 6.9L NA gets the same treatment.

There should be no issues with switching to synthetic at any time. This idea may have come from the aviation side, where a new engine (or one with a rebuilt jug) should be run on non-detergent oil for a few hours so the rings will seat.

Rotella T 15-40
Take it to the Bank
My 500 Cat has 540K on it and still uses a gallon in 5000 miles. Was that was when new and still right there. Ma Cat says thats good so off we go.

I use Delo 400 once in a while but usually the Rotella.
The little rigs here at the Ranch get Delo or Rotella depending on what I have a 5 gallon can of at the time they need a change.

I have always used a can of STP sticky stuff in my engines. Never seen a good reason not to. Use it in the Cat too. Just takes a buttload more to goo up 10 gallons of oil.

The way I see it and have seen it shown that the sticky stuff keeps lube in the bearings after a hot shut down.

I have had two rigs I used synth in and it was fine, I just question the $$$$$ outlay for any return.

Good luck

Robyn

STP is basically unnecessary. But, "Wait, there's MORE".

It does have downsides, being basically polyisobutylene. Not good.

Quote:

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Originally Posted by Robyn

..I have always used a can of STP sticky stuff in my engines. Never seen a good reason not to…

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Robyn,

There has been some discussion on this topic in the 6.2/6.5 Tech forum .. Several years ago Dr. Lee recommended the "red bottle" STP as a good source of ZDDP which is a is a anti-oxident & friction reducer .. per Dr. Lee its' kind of like a miracle drug for engines ... the latest oil formulations have reduced levels of ZDDP because it's not good for CATs and emissions if the oil gets by the rings and burns ... One down side of STP is that it also contains viscosity index (VI) improvers or thickeners ..

If you want to add ZDDP there are some other options.. Some of the folks over at BobIsTheOilGuy like a product made by Valvoline that contains ZDP and "moly" ... VSyn Oil Treatment – MSDS

Power Service was selling a Product called Diesel Lube Oil Extender that contained a good shot of ZDDP plus other Diesel add-pack components without the VI improvers .. I stocked up on it and use it to top off my Dmax between oil changes if needed .. It’s no longer listed on their web site but it I contacted PS a while back and they said it was still available … I’ve since seen it in Tractor Supply Stores …

Another point is that with the advent of ULSD there is less acid formed in the oil and therefore less impact on TBN .. I noticed that AVLube no longer recommends the TBN option for Diesel UOA’s.

For some more discussion here’s some threads in the 6.2/6.5 Tech forum …

Sulfur: Good, Bad or Ugly ?

ZDP in oil

Zinc Dithiophosphate


Oil Supplement/Synthetic Oil ?????


:)

:eek: Polyisobutylene, OMG :eek:

Oh well been using the stuff for years and had some very good luck with keeping bearings and such in good shape.

It seems that the more we learn the less we know.

I am not a chemist and certainly not an envirofreek.
I will admit that with the advent of many of the new emission controls many of the different products we used to think were great have proven to be detrimental to the new parts.

Yes Yes the ULSD will definately help keep the acid formation down due to the lower amounts of sulfur entering the oil from combustion gasses.

Anyway to get back to the original ????????

I would not give the Synth oil rave reviews simply because of the cost.
It seems to be a good product but I see no big huge advantage.

Possibly if the engine is beeing run under terrible conditions such as torturous heat for extended periods, maybe.

IMHO the average owner will never see any real benefit from the stuff.

Fuller offers a synth oil for the Road Ranger trannies in the big trucks
I had that stuff put in the new 18 spd in my Star when we did the box 2 years ago.
The tranny runs on average 100 F cooler.

My first box went 495K miles with just 50W mineral oil in it and never a problem.

The sucker was just plain worn out when they yanked it.
I have seen others that had used the Synth with half that many miles that were used up, so go figure.

I can't help but think that the biggest advantage "MIGHT" be for the seller of the product ???????? :D

Would be interesting to see some good fleet statistics where like equiped rigs run under like conditions were compared using Dino in some and synth in others with the operators not knowing what was used.

Good controlled studies with no bias.

Later

Robyn

My first box went 495K miles with just 50W mineral oil in it and never a problem.

The sucker was just plain worn out when they yanked it.
I have seen others that had used the Synth with half that many miles that were used up, so go figure.

I can't help but think that the biggest advantage "MIGHT" be for the seller of the product ???????? :D


Ya don't think it might be the difference between drivers and licence holders?:D

Zinc di(organo)dithiophosphate has been a common additive in diesel motor oil for years and years.

If one uses a diesel motor oil from a reputable supplier like Mobil or Shell, there is no need for additional additives.

Quote:

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Originally Posted by rustyk

Synthetic oils don't really provide enough benefit to outweigh the costs (IMHO)

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That's basically my opinion as well. I've owned 2 6.2ls that have gone to around 300K on Rotella T 15W40, and when I checked compression on the last one at around 280K it averaged 400psi with 1 hole at 360. It got 20mpg, didn't use a drop of oil, and Blackstone said to go 5K between changes. In the wintertime it didn't matter how cold it got, 2 hours of on-time for the block heater and warmer for the single Wal-Mart 875CCA EverStart and a seatbelt buzzer's worth of heat for the Kennedy quick-heats and she'd fire within 2-3 seconds and be running smoothly and almost smoke-free in 30.

So I had a choice - a $2 51794 filter (from a $24 lot of 12 I bought on eBay) and 2 $9 gallons of Rotella changed after 5K miles, or a $2 filter and spending close to $9/quart for Brand "A" and going maybe 15K on it. Given the engine's condition and how well it ran on Rotella T, to me it was a no-brainer to keep going that route.

5150

OH yes there is a difference there for sure.
Owners vs License holders. :eek:

I have seen owner operators that still did not know how to shift one of them big boxes without the thing making noise.

I learned from an old trucker, who by the way just turned 90 and still does a little local stuff for a friend when things get busy.
He told me " If your shifting is making noise yas aint doin it right"

I rarely use the clutch after the monster is rolling and then only under real hard pull up or down shifts. If im over 10 mph even on a hard pull the huge mass of the load will keep it rolling well enough to swap gears without even thinking about the clutch.

I hear these clowns all the time trying to get gears to fit. It just makes me cringe when ya see some lovely Pete let loose with a bunch of grinding and protesting noises as the fool up top is looking for a hole that it will fit in.

Now they have the new fully electronic air shifted 18 spds out there that all you do is select the go button and then let out the clutch and the computer does it all. Just mash the throttle and it automatically feathers the fuel swaps the gears and then fuels back up again without the driver ever removing his/her foot from the loud pedal.

THAT AINT TRUCKIN :eek: NOT EVEN
Also very uncool when it wont shift.

Does however save the fleet operator a metric buttload of $$$$$$$$$$ in repairs because of all the nitwit truck jockeys that couldn't grab a gear if they had a can full sitting on the seat next to them.

The driver can make a ton of difference for sure.

Robyn

:eek:

Quote:

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Originally Posted by Robyn

5150

OH yes there is a difference there for sure.
Owners vs License holders. :eek:

I have seen owner operators that still did not know how to shift one of them big boxes without the thing making noise.

Robyn

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Those are very special people. They are Machinist drivers. They grind um to fit!!
:D

Good Day!

Yup, it doesn't make economic sense to run synthetic, but there are other factors. I used to stock 5W-30 & 10W-40 Valvoline for ma's Buick, & 10W-30 & 15W-40 Rotella for the diesels, plus maybe some SAE 30 or 40 for the mowers, etc. Now I run 5W-40 Synthetic Rotella in everything, & only stock one oil.

Yup, you can take apart my usage of 5W-30 & 10W-40 (& others), but that's what I wanted to do, & 5W-40 makes my life real simple.

It was a lot easier decision when I got started - my daughter worked at WalMart, so I got a gallon of the Synthetic Rotella for $11.56, or $2.89 a quart. That was my price point - running synthetic for under $3 a quart. Unfortunately, their price has gone nuts. If I can get a reasonable price on Amzoil's 5W-40 (& I think I can), I might continue running synthetic; otherwise, it's back to stocking lots of different oils.

I also liked the idea of 5W when the engine's cold. I might be able to start my trucks at -30°F after they've been plugged in a couple hours, but I don't have any heat on the oil, & 15W just sounds too thick for me. 10W-30 was (last time I looked some years ago) the lightest winter non-synthetic diesel oil Rotella had, so that's what I used to run. To each his own, eh? ;)

Blessings!

After I put the 6.5l TD in my C1500 I decided I was going to run Rotella 5W40 synthetic in it. That lasted exactly 1 oil change, because I had to add a quart per week due to it burning oil. I went back to 15W40 dino juice and oil usage dropped to 1 quart per 2500 miles. Like you said, $12-something per gallon makes economic sense, but not when I had to add 2 extra gallons to make up for oil being burned. I'm thinking of trying Rotella synthetic with my Ram 1500 due to the recommended 7500-mile oil change interval, but I'm not sure how it'll like 5W40.

I ran Mobil 1 synthetic 75W90 in the diffs & trannies of my K10 and C1500 and that gave noticeable improvements in the wintertime. The dino 80W90 thickened up to almost the consistency of grease when temps dropped below 0F, and you could actually feel it when moving the shifter around.

Good Day!

(I knew I forgot to include something... :o) Unlike lots of other folks, I experienced absolutely no increase in oil consumption in any of the 3 where I made this change (the 89 & two 95s in my sig); if anything, they are using a little less oil than B4. Also, it still turns black after a change, but not as black & not as fast.

I have heard of many folks that had your experience; I was quite scared of this happening to me too, it just appears to be a bullet I dodged. ;)


Blessings!

(signature in previous post)

We took delivery of a '07 3500 with a Dmax and 6 speed ally in May, it now has 71k miles on it. the oil that came with the rig stayed in it untill 3400 miles, at that point I drained it out and replaced it with Convoy 15w40CJ4. I sent in an oil sample of the clean oil(right from the bottle) for a baseline. At 5k I took another oil sample, There was hardly a change in the report. At 10k I took another one, same deal. At 15k another, as well as a filter only and toped off the level. Finally at 30,000 miles I decided to finally change the oil, but the test still came back as usable. I am still just not content with the fact that I don't have to change the oil every 7k like We used to in our other trucks.

so for just that one truck so far, using CONKLINs convoy 15-40CJ4 has saved us, lets see here

7Quarts of Convoy 15-40 @ 7.344 a Quart total cost $51.40

Filter @ $21.95

cost of oil change $73.35

Oil analyst cost 5 @ 10.53 a pop = $52.69

Total cost to run same oil for 30k = $126.04 pluse $10.53 for the baseline test.

so to run with the normal program of Shell rotella 15-40

7 Quarts @ $4.50 a quart(bulk case) = $31.50

Filter @ 21.95

cost of oil change every 7k = $53.45

53.45 x 4.28(to equal mileage) = $229.07

now We never did oil samples on the rotella but my the time it was up to 7k miles the oil pressure was lower then normal and the truck started using a little oil.

so by my findings we save $103 for every 30k miles we drive that truck.

I have also switched over to Conklins Gold guard plus gear oil 75-90 and there ATF-Extra(with this ATF we have noticed the tranny's run cooler then they used to.

By doing these things to our trucks we have realized an average or 8% better fuel economy. for a company that puts 72+k miles on each of the 4 rigs in the yard per 4 months this has netted us substantial savings.

The company owner is now using Conklin products in his personal trucks as well as his and his wifes Harley Davidson's


I made the switch to this different maintenance program with out telling any of the other drivers, so I can safely say that the fuel gain is not from them driving the rigs nicer to make it look good. I still have not told them.


*** NOTE: I have no affiliation with Conklin or serve to gain anything by this "testimonial/Information" this is just plane observation*** I was turned on to these products from a friend of mine that lives in Minnesota and is a Farmer and uses this stuff.

Excellent info. Thanks for sharing.

7 quarts? Your Duramax sump is 10 quarts.

Your results sound impressive, but... The front & rear differential are spec'ed for synthetic lube, and your owner's manual specifies 7500-mile engine oil drain intervals. An anal dealer could, in a worst case scenario, void coverage if GM felt the vehicle wasn't maintained according to what's required by the engine and powertrain warranty.

Synthetic lube is required by the rear differential because of its higher resistance to breakdown due to heat. Dodge discovered years ago that the rear differentials used in trucks that tow heavy for long distances in high heat routinely failed when running a conventional petroleum gear lube. All of the Dodges and GM's now get synthetic lube as a result. Both Dodge and GM diesel pickups use the AAM1150 rear differential.

Jim

ah yeah 10 Qts, it has been a long while so I couldn't remember the amount and figured 7 sounded about right.

THIS IS THE GEAR OIL I USED

THIS IS THE OIL I USED

After reading this forum from the beginning I have some questions about what type of engine, tranny, and gear oil to use.

I have a 94 6.5 turbo with 152k miles on it. My grandpa bought it new and my brother had it about 4 years before I got a hold of it last summer. I know for a fact the engine oil was changed every 3-4k miles but with Dela 400 and usually a napa, wix, or sometimes a fram :( filter. As for the transmission, I don't know when it has been done or with what oil. The rear end I doubt has ever been touched, and probably still has factory seal on the cover. I currently have a few oil leaks from the turbo, the valve covers, the fittings on the oil cooler lines by the oil pan, and maybe a rear main. During the last oil change i ran the truck about 4 k miles and only added maybe 1 qt, probably not even that much. So, the leaks aren't bad. I usually park the truck and I get about 3 or 4 spots the size of a dime or smaller. Not very big leaks at all.

I have been thinking of running amsoil or another syn. oil but am now worried of my leaks getting worse. Also, the truck has always run dela 400 and this last change has run Lucas 15w-40 heavy duty diesel engine oil. What oil should I run for my engine, tranny, and rear end? Dino or syn? Rotella, dela, or mobil 1 or even another brand? My truck is mostly stock but is out in orchards for farming a lot and is exposed to dirt a lot. Other than that most of the driving is in town, daily driving.

Sorry, for the long question, please bear with me though. I am just trying to catch up on maintenance for a more economical and reliable truck.

I'd snug the bolts up a little on the valve cover gaskets and continue to run the Delo 400 and change it just like before. The 4L80E, I don't think I would switch to synthetic on it, just the dexron that was recommended for it when new, if you can still find it, but convention trans. fluid (Dexron) is what I'd use. The differential, yeah, go with the synthetic, either GM's or Mobil 1 or Amsoil.