Thread: 4BD1T oil

Isuzu would not make their own oil.

I usually use Castrol RX Super, however switched to Penrite Japan Truck on my last oil change as I have heard very good things.

pretty much any 15/40 is the go.

semi synthetics nice but not needed....

I am having great success with RX Super and highly reccomend it - i have been using it int my diesle landrovers for almost 10 years.

FWIW When I fitted the 4BD1T to my Defender I researched engine oils. Castrol told me that the "Jap spec" oils had a higher ash content to reduce lubricity to allow the rings to seat better in engines with chrome bores therby improving oil control, and told me that if the engine did suffer from excessive oil consumption to stick with RX Super or better as it had higher lubricity than the JMax. After more than 55000ks (total mileage about 120000ks) my Isuzu is not using any oil, the oil is staying remarkably clean for a Jap diesel engine, and it is running very very well.

As an aside I used RX Super in the 300 Tdi and when I checked the main bearings at about 180000ks they looked like brand new, as did the rest of the engine with zero deposits or carbon build up. Engine builders I have spoken to have indicated that engines run om RX Super are genrally very clean inside.

CHT

Originally Posted by C H T

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FWIW When I fitted the 4BD1T to my Defender I researched engine oils. Castrol told me that the "Jap spec" oils had a higher ash content to reduce lubricity to allow the rings to seat better in engines with chrome bores therby improving oil control, and told me that if the engine did suffer from excessive oil consumption to stick with RX Super or better as it had higher lubricity than the JMax. After more than 55000ks (total mileage about 120000ks) my Isuzu is not using any oil, the oil is staying remarkably clean for a Jap diesel engine, and it is running very very well.

<snip>
CHT

This is generally in the form of calcium at greater than 3000ppm, compared to most diesel oils at around the 2500-2800 mark, depending on the add package.

I'd debate the lubricity comment, the extra calcium is a bit more insurance against cam wear and scuffing and even exxy oils like Amsoil AME 15W-40 have greater than 3000ppm calcium.
I'm thinking 'lubricity' and 'friction modification' might be getting confused here.

Originally Posted by isuzurover

Isuzu would not make their own oil.

I usually use Castrol RX Super, however switched to Penrite Japan Truck on my last oil change as I have heard very good things.

Interesting comment Ben.

I've swapped over to Penrite, in this case Diesel SP 10W-40 as a trial on the recommendation of my oil analyst in the Patrol and Tdi.
He's been very surprised at the results from their SIN range in customer engines.
His 'best' recommendation was a US made HOBS based synthetic, but it was just too hard to source it at the time, but I'll probably try it eventually.

Castrol RX Super. No problems and no oil consumption.

Originally Posted by rick130

This is generally in the form of calcium at greater than 3000ppm, compared to most diesel oils at around the 2500-2800 mark, depending on the add package.

I'd debate the lubricity comment, the extra calcium is a bit more insurance against cam wear and scuffing and even exxy oils like Amsoil AME 15W-40 have greater than 3000ppm calcium.
I'm thinking 'lubricity' and 'friction modification' might be getting confused here.

My reference to lubricity was a simple quote from the Castrol tech that I spoke to - his terminlogy not mine - he explained that the Jap spec oils have lower levels of "lubricity" for the reasons mentioned in my previous comment.

CHT

Originally Agricastrol 15w40 when engine was in the 110 from new, after the swap to my RRC it has run Valvoline super diesel, and now Pennzoil Diamond fleet 15w40. I too have almost zero oil consumption (550,000km now)
I also use this oil in my LT95, which I change every engine service because I can...
JC