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I'd use 10W40 and minimise your oil stores.
that temp chart doesn’t go far enough to the left for my winters!!
i do garage mine though. but it sits outside all day while at work. i use 15-40 synthetic all year but should likely use 10-40 in the winter. i have a webasto which warms the engine to operating temp when colder than -10C so that also makes a big difference. i always use a toyota filter
i’ve got 600 000km on the clock so it doesn’t seem to have been detrimental for the last 300k i’ve put on myself
i do garage mine though. but it sits outside all day while at work. i use 15-40 synthetic all year but should likely use 10-40 in the winter. i have a webasto which warms the engine to operating temp when colder than -10C so that also makes a big difference. i always use a toyota filter
i’ve got 600 000km on the clock so it doesn’t seem to have been detrimental for the last 300k i’ve put on myself
The solution to your oil queries is right there ^^. Use that for your 1HD-FT and your life gets way simpler.
The only reason not to is cost. I use a Motorex 5W30 that's VW approved for all my newer engines and a cheaper 10W40 for my 4BD1T.
All these oils are far better than the ones available when your engine was designed.
Diesel engine oils usually have more detergent to help remove soot/carbon from the oil, and zinc compounds to help lubricate/ reduce wear in bearings.
Oil with 1200ppm ZDDP zinc/phosphorus compounds is recommended for diesels to improve bearing longevity.
Gasoline engine oils will have a lot lower zinc content, or no zinc as zinc clogs catalytic converters.
I'm no expert, but a bit of a searching knowing that ^^^ you'll find plenty of info to help make a decision without going full "Bob The Oil Guy".
I've used diesel oils in petrol engines for a few oil change cycles to clean gunk out. I wouldn't go the other way though.
Just reading on "Bob is the Oil Guy" and it looks like the Delvac has been reduced in zddp (zinc) additive. That stinks. Still good oil but the high zinc content was what I have been after.
There is a new consensus for "Mobil 1 Turbo Diesel Truck 1300 ppm Zinc. Mobil 1 V-Twin 1750 ppm Zinc."
I might give those a shot but no idea what viscosity they can be bought at.
OR... maybe just dump in a zinc additive and stay the course otherwise.
There is a new consensus for "Mobil 1 Turbo Diesel Truck 1300 ppm Zinc. Mobil 1 V-Twin 1750 ppm Zinc."
I might give those a shot but no idea what viscosity they can be bought at.
OR... maybe just dump in a zinc additive and stay the course otherwise.
I already dump additive in my diesel fuel for lubricity, why not the oil?
Remember when diesel used to lay on the ground forever when it was spilled rather than evaporate like gasoline? That can't be good for a diesel engine, especially an old one.
Remember when diesel used to lay on the ground forever when it was spilled rather than evaporate like gasoline? That can't be good for a diesel engine, especially an old one.
I promised myself I wouldn't wade into these oil debates but here I am.
The spec for a 1hdt/FT is JASO-DH1 - this is an ancient spec from 30 years ago. Pretty much any oil will be fine. I use whatever diesel mineral oil is on special at the FLAPS near oil change time. I've run Penrite, Gulf Western, Castrol, Nulon, basically everything that's on the shelf here in NZ.
Bottom line is that all modern diesel oils are better than what was around in the early 90s. Buy whatever is on special and change it often.
The spec for a 1hdt/FT is JASO-DH1 - this is an ancient spec from 30 years ago. Pretty much any oil will be fine. I use whatever diesel mineral oil is on special at the FLAPS near oil change time. I've run Penrite, Gulf Western, Castrol, Nulon, basically everything that's on the shelf here in NZ.
Bottom line is that all modern diesel oils are better than what was around in the early 90s. Buy whatever is on special and change it often.
If you’re really concerned about how an oil performs in your engine run it for a change interval and then send a sample off to an oil analysis lab to have it tested. Only about $40 and they give you a full report on all the different metals, elements and other stuff they find and compare it to similar engines.
I use Shell Rotella T4 15w-40 in older diesels (12v and 24v Cummins, 1HD-T, OM617) and Rotella T6 5w-40 in my VW TDI.
Edit: the oil change intervals I run are 3000-5000 miles for the vehicles with T4 (conventional oil), 6000 miles for the tuned and heavily worked TDI, and 10,000 miles for the stock TDI. Oil analyses on these engines show that these intervals are well within the oil's lifespan.
I use Shell Rotella T4 15w-40 in older diesels (12v and 24v Cummins, 1HD-T, OM617) and Rotella T6 5w-40 in my VW TDI.
Edit: the oil change intervals I run are 3000-5000 miles for the vehicles with T4 (conventional oil), 6000 miles for the tuned and heavily worked TDI, and 10,000 miles for the stock TDI. Oil analyses on these engines show that these intervals are well within the oil's lifespan.
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Just getting into a a 3B and know about flat tappet oils from the 2F cam history.
Based on what I see, Mobil 1 Turbo Diesel 5w-40 is the way to go. Good start up weight to quickly build pressure and a nice zddp package. A little pricey oil but you get what you pay for here.
They had the 1 gal on sale for $30 at O'Reilly's and I stocked up enough for a few OCIs.
Based on what I see, Mobil 1 Turbo Diesel 5w-40 is the way to go. Good start up weight to quickly build pressure and a nice zddp package. A little pricey oil but you get what you pay for here.
They had the 1 gal on sale for $30 at O'Reilly's and I stocked up enough for a few OCIs.
That is kind of interesting. I don't have a turbo but wonder what the logic is with 32F.
All engine oils these days are dual rated. They have a spark ignition (petrol/gas) rating and a compression ignition (diesel) rating.
They are all majorly better than they were 30-40 years ago. Diesel engine oils used to be better at handling soot, but it's not really an issue now.
Diesels these days have catalytic converters and diesel particulate filters. So the old anti-wear additives are basically gone and new antiwear additives do the same job but aren't ZDDP.
There is nothing in a 1HD-FT that requires special oil. It doesn't have cam driven injectors or any of those risks. The crank bearings on a 1HD-T however are 100,000km service items due to cavitation and there is nothing you can do with oil type to change that. The FT fixed that and runs cleaner.
Additives are just wasting money. It's not even a high stress application. You've got a lot of oil capacity on a large diesel that barely gets warm and runs low boost.
Agreed apart from the "changing it regularly" thing. Oil should be changed when it's needed and doing so more often just wastes time and money.
IMO 3000-5000miles is madness. It's not the 1960's any more. Many vehicles now are north of 30,000km and John Deere are advertising diesel oil with 500 hour oil change intervals.
5W40 is fairly thick for a tdi. I run 5W30 in mine and it's got an oil quality sensor that tells me when it needs changed. This is usually around 24,000km (16k miles).
My engine is a Pumpe Duese which can wear out cams with the wrong oil. But with over 200,000km it's still working great.
The FSM would have been written in the late 80's when oils were terrible. Everything turbocharged now runs maximum of 5W30. Oils have a HTHS (high temperature high stress) test which is done at 150C. Even 0W oils pass these tests fine.
