What's your avg speed/ OCI in terms of hours?

[BlakeB]

How many hours/miles does your truck/vehicle have? I'm seeking information on a Duramax specifically, but if you have data to add from other vehicles (gas or diesel, please do.

We have a 2016 Duramax LML, 3500HD.... Flatbed, nothing special. Bone stock, not deleted. This truck is used as a work truck/daily driver. It accumulates over 3 hrs of runtime daily, its average speed is 14.7 mph thus far. I ran the factory oil and filter for an entire OCI, until the OLM hit 0%. I ran the second oil change till the OLM hit 0% as well. Heres the breakdown:
*Bought new 12/23/16* Oil used (after factory fill): Delo 400 SDE 15w40 along with M1-303A or PF2232 filter.
OCI #1 (5/27/17) 7,684 miles, 534.5 hours. OLM=0%
OCI #2 (10/31/17) 7,404 miles, 491.8 hours. OLM=0%

In total, at the last oil change, the truck had 15,088 miles and 1,026.3 hours, giving me an average speed of 14.7 MPH.

By following the oil life monitor I am seeing OCI's of about 7,500 miles/ 500 hours. Should I be changing the oil sooner than this? These trucks have a relatively small sump, is a 500 hour OCI pushing too far on 10 quarts of (non-synthetic) oil?

A few things to note, this truck has daily short trips of less than 1 mile, and a fair amount of idle time. It is ran at operating temp daily, it averages just over 3 hrs of run time each day, 7 days per week. This truck is used regularly for towing/hauling as well as unloaded (passenger type) regular daily driving, it required 2 quarts of makeup oil during its last OCI.



I know this is the wrong place to ask, but what about servicing the transmission, GM says to change the fluid and (spin-on) filter at 45,000 miles under severe service. These transmissions are factory filled with Dex VI, and GM gives no recommendation on a basis of hours in operation. I'm thinking a drain/fill and spin-on filter change every 1500 hours or less with Dexron VI?
Here is what Allison recommends (using their fluids):


I'm thinking that I may have to service this truck more in terms of hours, instead of miles. From what I can gather, regular service implies something along the lines of 25-30 mph. I know that Ford specifies 25 mph as regular usage, so we'll use that as our number for arguments sake.
Now, lets take engine coolant for an example:
Recommended change interval, 5 years/150,000 miles. (150,000/25 mph = 6000 hours) (150,000/30 mph = 5,000 hours)
My actual usage (150,000/14.7 = 10,204 hours), or lets figure 1500 hours per year. (1500x5= 7,500 hours)

I'd love to hear what you guys think, If you want to see the oil filters from my 1st and 2nd OCI, see my thread
PF2232, M1-303A. Thanks!

 

[AITG]

I had a Duramax LB7 for about seven years and I followed the OLM and took used oil analysis at each change. I learned that these engines are very easy on oil. At one point I went four years on a change and the oil sample came back just fine. I would follow the recommendations on the transmission. While Allison has an excellent reputation, the 1000 series transmission is a light duty item. As long as you aren't cranking up the engine with a tuner it will last a fairly long time. I would definitely switch it to TranSynd. It handles the heat of towing much better than Dexron.

 

[i_hate_autofraud]

It’s truly staggering the accumulated hours a auto / truck engine can have! Of course it’s possible since you can cruise the hiway with 30 HP on an engine capable of 300 HP for hours at a time! Aircraft engines running full power at take off and 60 – 80% power during flight means a 5,000 Hr TBO is nothing to scrimp on! Since you have a spin-on tranny oil filter, see if the steel shell is .020” thick or less, then you can use FilterMags or individual magnets on the shell to pick wear metals in the ATF. If your spin on filter has a shell .025”, FilterMags are less effective. At .030” or more, it’s not possible to use standard FilterMags and get results. See the results in this PDF: I’ve been able to get the same results too, so I’m happy. “ FILTERMAG vs HOMEBREW “ https://app.box.com/s/uxvu8dmscf5wcgftutdm0ejqwgn86tw7

 

[BlakeB]

Originally Posted By: AITG

I had a Duramax LB7 for about seven years and I followed the OLM and took used oil analysis at each change. I learned that these engines are very easy on oil. At one point I went four years on a change and the oil sample came back just fine. I would follow the recommendations on the transmission. While Allison has an excellent reputation, the 1000 series transmission is a light duty item. As long as you aren't cranking up the engine with a tuner it will last a fairly long time. I would definitely switch it to TranSynd. It handles the heat of towing much better than Dexron.

That's what I've gathered as well, on the oil. I think I will continue to follow the OLM, I haven't been able to find any evidence of anyone having any issues in doing so.
When you say you would follow the recommendations on the Allison, which recommendations are you referring to? Allison or GM? 45,000 miles at 30 mph is 1,500 hours, or 1,800 hours at 25 mph. From everything I've read, the Allison's tend to do well on Dex 6, as well as TES-295 as long as its changed at appropriate intervals. The UOA's I have come across have indicated that Dex 6 is getting about the same wear numbers as 295/295 clone fluids. The forums seemed to me to have the consensus that the Allison transmission is much like the Duramax, they aren't too picky about what kind of fluid they have as long as its fresh. As far as heat goes, this trucks transmission runs on the cool side, 145F or less usually. I have never seen it over 200F, I actually don't think I have ever seen it over 180F, and that includes a lot of low speed towing with a fully loaded gooseneck at over 24,000 lbs. I don't know what temps I'm getting at the TC, but the temps can't be too hot or the pan temp would be higher than it typically is.
Side note, our old (2013) 6.7 F-250 would sometimes get into the 230-240F (not good, i know...) degree range (engine and transmission) towing the same load.

 

[Toptierpao]

I use my truck in a similar fashion.Any car or truck with a turbo should be using synthetic oil.Allison,manufacturer of fantastic transmissions, specs that fluid for a reason,I would and do use it.I would also be thinking about changing differential fluid.

 

[userfriendly]

2011 LML new in 2012, 124,600 km 1926 hours. I usually change around 10k kms, between 100-200 hours.

 

[BlakeB]

Originally Posted By: userfriendly

2011 LML new in 2012, 124,600 km 1926 hours. I usually change around 10k kms, between 100-200 hours.

124,600 km= ~ 77,423 miles 77,423/1926= 40.2 mph average speed 100x40.2= 4,020 mile OCI @ 100 hours 200x40.2= 8,040 mile OCI @ 200 hours 10,000 km is 6,213.7 miles. 6,213.7/ 40.2= 154.6 hours average OCI. All these numbers are approximate, thanks for your input!

 

[userfriendly]

That looks about right Blake. The long 200 hour intervals are during shorter winter trips, idling and driving slow. I've seen OCIs around 80 hours with average speeds close too 100 kph and fuel consumption around 12L/100 kms. Fuel use during winter is 15L/100k. Maybe changing oil per gallon of fuel burned instead of time or mileage would make more sense. Many factors affect my winter fuel economy such as tires, lubricant viscosity in the engine, transmission, diffs and transfer case as well as road conditions and warming up the truck to get the frost off the windows. (275/65/20 studded Hankook RW-11s) Often a season change will necessitate an early oil change as I save synthetics for winter and have an SAE40 addiction.

 

[BlakeB]

I've thought about the fuel comsumption thing a lot as well, but I'm not sure it would be a super accurate way to determine an OCI either. For example, my 2007 Tacoma with the 4.0 V6 will burn about 1.1 GPH driving it as I normally do, high idle times, short trips, and a little mixed driving, average speed of 12-13 MPH usually. If I put it on the highway at 65-70 MPH it will burn ~3GPH, one hour on the highway is a lot easier on an engine and oil than an hour of idling and stop and go driving, is it not? That's the data, according to my Ultragauge, for my last OCI on the Tacoma. I know on the Ford Superduty trucks they used to say 5,000 miles, 250 gallons of diesel burned, 200 hours or every 3 months, but those engines had oil fired injectors and were bad about shearing oil down quickly. https://www.fleet.ford.com/truckbbas/non-html/DeiselTips/DLSIDLETIMESS.pdf

 

[TiredTrucker]

Originally Posted By: Toptierpao

Any car or truck with a turbo should be using synthetic oil.

Probably a good idea, but one would have to explain how it is that thousands upon thousands of commercial heavy, turbocharged working engines go over 1 million miles and 20,000 - 25,000 engine hours on conventional lubricants without major engine repairs or even a turbo replacement.

 

[Garak]

Shhh, oil companies and nervous nellies have sold a lot of synthetic based on turbo paranoia.

 

[BoiseRob]

Originally Posted By: TiredTrucker

Originally Posted By: Toptierpao

Any car or truck with a turbo should be using synthetic oil.

Probably a good idea, but one would have to explain how it is that thousands upon thousands of commercial heavy, turbocharged working engines go over 1 million miles and 20,000 - 25,000 engine hours on conventional lubricants without major engine repairs or even a turbo replacement.

TT, those OEM's must be wrong since DELO 10w30 is factory fill for Paccor & Freightliner... lol

 

[dnewton3]

Yup - I'm sure my Dmax is on death's doorstep after running 53k miles of dino 10w-30 HDEO. I've probably cut 10 miles off it's 500k mile lifespan using conventional oil .... As for the tranny fluid, the Allison 1000 in these trucks is built by GM; it was designed by Allison when GM owned them. I would agree that TES-295 (the fluid spec for Allison syns) is an excellent choice. But so are a whole host of other syns; you don't "need" a TES-295 syn. In fact, Allison also approves conventional oils; TES-389 that are essentially what was formerly a Dex III fluid with considerations for seal compatibility. GM's DEX VI has proven to be a stellar fluid in these transmissions as well. Not one person running these personal trucks works it "severe" service by Allison definition. Allison defines "severe" as typical of trash trucks, city buses, shuttle transport vehicles, etc. These see very low average speeds, with heavy loads, for long service cycles, flashing the TC with WOT application so the TC doesn't end up locking up. This is not akin to someone here towing his heavy 5ver across the nation. While we want to think we're "severe", most all of us don't meet the real intent of Allison's definition. In truly "severe" (meeting Allison criteria) situations, then TES-295 and the clones can be of benefit. Short of that, the macro data shows it just does not matter, and overly frequent fluid/filter changes are a waste. The Alli 1000 is akin to the Dmax; it really does not care what fluid is used in most situations; it wears well overall. I've got over 200 UOAs from these Alli 1000 trans in all manner of applications; the data speaks for itself. Pick any Dex/Merc type fluid you want, keep the fluid temp below a sustained 250F, change the fluid and spin-on every 50-75k miles, and quit worrying. .

 

[billt460]

It's amazing how low the average speed of a vehicle is over it's lifetime. Before I retired I always used to laugh at guys when the whole discussion of, "how long does it take you to get to work", started. Guys who lived 30 miles away were always bragging how they made it to work in 25 minutes. What a crock. They forgot that in order to average 70 MPH, you have to drive 140 MPH for every minute you wait at a stoplight for that same amount of time.

 

[CarbonSteel]

Originally Posted By: dnewton3

Yup - I'm sure my Dmax is on death's doorstep after running 53k miles of dino 10w-30 HDEO. I've probably cut 10 miles off it's 500k mile lifespan using conventional oil ....

Ah...the days of non SCR/DPF/DEF

 

[dnewton3]

Originally Posted By: 2015_PSD

Originally Posted By: dnewton3

Yup - I'm sure my Dmax is on death's doorstep after running 53k miles of dino 10w-30 HDEO. I've probably cut 10 miles off it's 500k mile lifespan using conventional oil ....

Ah...the days of non SCR/DPF/DEF

I know - right?!?! Every time I think I might want a new truck, I look under the hood of a new diesel (any of the brands) and quietly cringe at all the junk under the hood and chassis. They actually run great and make fantastic power; but someday, somehow, somewhere, all that stuff will need to be fixed and/or replaced. OUCH!

 

[CarbonSteel]

Originally Posted By: dnewton3

Originally Posted By: 2015_PSD

Originally Posted By: dnewton3

Yup - I'm sure my Dmax is on death's doorstep after running 53k miles of dino 10w-30 HDEO. I've probably cut 10 miles off it's 500k mile lifespan using conventional oil ....

Ah...the days of non SCR/DPF/DEF

I know - right?!?! Every time I think I might want a new truck, I look under the hood of a new diesel (any of the brands) and quietly cringe at all the junk under the hood and chassis. They actually run great and make fantastic power; but someday, somehow, somewhere, all that stuff will need to be fixed and/or replaced. OUCH!

I feel your pain brother. Zero room under the hood of my PSD. In fact, I read on many of the PSD forums that for any "substantial" repair, they simply remove the cab of the truck. Definitely removes the "do it yourself" feature from these trucks (for the most part). My guess the cost of the replacement emissions components is what drives the "delete" market.

 

[Shannow]

Originally Posted By: TiredTrucker

Originally Posted By: Toptierpao

Any car or truck with a turbo should be using synthetic oil.

Probably a good idea, but one would have to explain how it is that thousands upon thousands of commercial heavy, turbocharged working engines go over 1 million miles and 20,000 - 25,000 engine hours on conventional lubricants without major engine repairs or even a turbo replacement.

When turbos hit petrol engines, they were not water cooled, and were operating on an engine that was running stoichiometric (or very close) 100% of the time. And coke was produced that cooked bearings...synthetics did better, much better. The fact that at the OTR diesels at the time, which NEVER operate stoichiometrically didn't do it on dino is pretty non equivalent.

 

[roadrunner1]

Originally Posted By: Shannow

Originally Posted By: TiredTrucker

Originally Posted By: Toptierpao

Any car or truck with a turbo should be using synthetic oil.

Probably a good idea, but one would have to explain how it is that thousands upon thousands of commercial heavy, turbocharged working engines go over 1 million miles and 20,000 - 25,000 engine hours on conventional lubricants without major engine repairs or even a turbo replacement.

When turbos hit petrol engines, they were not water cooled, and were operating on an engine that was running stoichiometric (or very close) 100% of the time. And coke was produced that cooked bearings...synthetics did better, much better. The fact that at the OTR diesels at the time, which NEVER operate stoichiometrically didn't do it on dino is pretty non equivalent.

But now almost every turbocharged engine produced is liquid cooled, and has been for years. The last diesel engine I saw with an air cooled turbo was a Detroit 6V92 from the early 90's we had bought for a boat. It came from the factory with blankets for the turbos as they claimed to be more efficient with the heat held into them, and pryometers to ensure they didn't run too hot. I'm sure there are engines produced with air cooled turbochargers today, but not in automotive. Back on topic, my '15 F350 6.7 has 71,528 mi. and 1482 hrs., which works out to 48.26 mph

 

[BlakeB]

I found this note on my phone today. From our old 2013 PS 6.7 F250 55,477.1 miles 3,441 engine hours 1392 idle hours 55,477.1/3,441= 16.12 Total Average MPH 55,477.1/2,049 (3,441-1392)= 27.08 Average In motion MPH This truck had ~70k miles when we traded it, I can't remember exactly though.