If you're running oil analysis you can ignore the factory intervals and go by the reports.
9L of oil every 5000km seems crazy to me.
Oil change questions HDJ81
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If you're running oil analysis you can ignore the factory intervals and go by the reports.
9L of oil every 5000km seems crazy to me.
What does your analysis say after that far?
After 5000km? Everything is normal. They've asked if I want to check on extended intervals and I declined
There are 100's of these threads around.
The spec for 1HDT oil is API CC or CD, or Jaso DH-1. My limited research suggests that the Jaso bit is important for keeping the top ring clean and having enough ash content. These are all ancient specs, and CC is considered only for pre-1990 engines. Locally in NZ there are only a few oils that list these specs (Gulf Western Tough Dog, Penrite Diesel FX and the Valvoline that goes on special at the FLAPS).
Loads of modern synthetics are "better" oils but they're designed for longer service intervals etc, so changing them every 5000-7500k is pretty pricey for minimal gain.
Run a quality mineral oil that lists the Jaso spec and change it often. I aim to change mine every 5k but it usually ends up around 7.5k. At current usage that works out to about 1.5 changes a year. I don't know much about oil but i feel like it sitting around for a year or given how moist and humid the weather here is isn't a great idea.
And if anyone cares I'm running Tough Dog XDO. Seems fine. Good oil pressure, stays clean (as clean as any oil in an old diesel) and economy seems fine.
The spec for 1HDT oil is API CC or CD, or Jaso DH-1. My limited research suggests that the Jaso bit is important for keeping the top ring clean and having enough ash content. These are all ancient specs, and CC is considered only for pre-1990 engines. Locally in NZ there are only a few oils that list these specs (Gulf Western Tough Dog, Penrite Diesel FX and the Valvoline that goes on special at the FLAPS).
Loads of modern synthetics are "better" oils but they're designed for longer service intervals etc, so changing them every 5000-7500k is pretty pricey for minimal gain.
Run a quality mineral oil that lists the Jaso spec and change it often. I aim to change mine every 5k but it usually ends up around 7.5k. At current usage that works out to about 1.5 changes a year. I don't know much about oil but i feel like it sitting around for a year or given how moist and humid the weather here is isn't a great idea.
And if anyone cares I'm running Tough Dog XDO. Seems fine. Good oil pressure, stays clean (as clean as any oil in an old diesel) and economy seems fine.
Interesting. Rotella T6 is Jaso DH-2, looks like DH-2 was designed for EGR so lower ash content. And sulfur. And that's not good for our engines?!?
DH-1 vs. DH-2
Also the TBN is allowed to be lower in DH-2, but Rotella T6 5-40 has TBN of 10.1 which exceeds DH-1.
Hard to find DH-1 spec oils in the US it seems!
DH-1 vs. DH-2
Also the TBN is allowed to be lower in DH-2, but Rotella T6 5-40 has TBN of 10.1 which exceeds DH-1.
Hard to find DH-1 spec oils in the US it seems!
We don't get Rotella here in NZ but we do get Rimula that is Jaso DH1.
I'm getting to the extremities of my knowledge but I gather that the Global DHD-1 meets the JASO spec too.
https://penriteoil.com.au/assets/pdf/tech/Nov2015/Engine_Oils.pdf - info on P7 about JASO interchange.
Wow!! Makes sense given that it's taking all the friction, but that's a pretty amazing number.
I believe you are correct, it seems like Global DHD-1 is the appropriate standard to look for moving forward:
Rotella T6 is not Global DHD-1.
A zinc additive is recommended in your oil for the valve train. And l always use Lucas conventional heavy duty oil additive at 20% (in tranny, diffs, tcase too). I've been changing oil and filter at 10k. 1hdt at 270k km. Got a change coming up, will send sample off and see!
Put lubricity in your diesel to protect the IP and injectors w every fillup (opti-lube.com). Sulfur is a lubricant, and its not in diesel anymore. You cant replace your IP: protect it!
Put lubricity in your diesel to protect the IP and injectors w every fillup (opti-lube.com). Sulfur is a lubricant, and its not in diesel anymore. You cant replace your IP: protect it!
Stateside diesel fuel is required to meet minimum lubricity standards that were established prior to when ulsd became available. The lack of sulfur requires diesel suppliers to add lubricity compounds to their mix. So while adding more isn't going to hurt, it's unlikely to be needed.
Rotella t4's zinc content is higher than what is recommended even for old flat tappet cams.
While delo and delvac are both just below the threshold.
Again, many of us run oil analysis and show no excess wear just running standard diesel oil.
If you want to spend money on additives by all means. But at least bring data to back it up.
Aye. Good to know that about T4.
I'd question trusting oil companies more than the worth of investing in (excess?) lubrication. I aint gonna stop adding lubricant to my diesel.
I am curious what kills these trucks when they die of wear.
I'd question trusting oil companies more than the worth of investing in (excess?) lubrication. I aint gonna stop adding lubricant to my diesel.
I am curious what kills these trucks when they die of wear.
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The oil specs superceed and the old ones become obsolete. Just because an oil doesn't list, for example, JASO DL-1 spec doesn't mean it won't exceed that standard. Certificiations cost and there are so many competing and obsolete ones that oil companies won't bother.
Requiring a CC/CD spec means that anything newer is also fine. Those are very old specs.
The 1HD-T doesn't have any special oil requirements. It's not a high speed diesel, it doesn't have EGR or DPF or unit injectors. It's not running under high stress or high temps. It doesn't suffer from abnormal cam wear or anything like that.
The biggest issue it has is cavitation in the big end bearings and the only way to manage that is to keep replacing the shells.
Ash content was a measure of the additive pack of an oil. But that measure is gone. Becaus EGR and DPF forced oil companies to produce additives which burned to almost no ash otherwise they clog up the DPF's.
If you're changing oil every 5,000-10,000km in a stock engine then you can use almost anything. IMO changing oil every 5,000km is a waste of money and oil for zero benefit.
Do you see a lot of 1hdt's dying?
Why not? Do you think oils haven't improved in the last 3 decades?
I don't run a synthetic. So possibly. But it's not something I'm willing to chance. Especially since 5000 km is like 6 months for me.
You're not chancing anything. Your oil analysis says there are no problems.
It's also not said I can stretch them out
And regardless of mileage I'd be changing my oil ever six months anyways.
All my toys get an oil change in the fall and spring. Usually April and October.
I dont see any 1HDT or FTs out there, as it were. Rather unique rig. But there are a lot of them, and l'm curious what kills or wears out on them in masse, in a broad statistical sense. The high wear, high expense components. Like the BEB issue. The block aughta go 1mil miles? Neglect and trauma kill them. What else
Lubrication = life blood.
I guess my point was, where are you seeing these engines die? I don't see a lot of 1hdt failures.
The beb issue was due to the material used by Toyota. Maintenance exasperated the issue.
