Thread: 4bd1 (or later 4bd1-T) Oil - M1 Delvac?

After trying a few different ones I settled on Mack EOS-4.5 diesel engine oil for the past year. Started with one truck, now running in all three. Thusfar could not be happier.

All will be fine for Australia.

I have used Castrol RX Super (15W-40) and have had trouble free running in all my diesels for years.

I'll stick my neck out and post that IME the LR tdis and Isuzu 4BD1s are old tech and do not need the latest expensive synthetics.

I look forward to reading what Rick130 posts

What ever is on special

Originally Posted by Vern

What ever is on special

This ^

The major difference is that Delvac 1 can go longer between drains if you so desire and at extremes of operation will protect a little better, but no one ever really gets there, despite what they may think.

Thanks.

Since delvac 1 can go longer between drains, does that in any way mean protects better or is that basically they protect the same just one does it for a longer time period?

How much difference would we be talking here in terms of "one can go further between changes"?

I spoke to M1 and they told me the ESP M1 on trucks get changed every 30-40,000 km.

I mean from my regular 10k per oil service on my regular car, 40k is HUGE difference.

Why would a person not want a very long drain interval? I mean it only means less cost on maintenence the further it goes...

I was always under the impression that full synthetics would always in the long run be better than mineral based oils (for petrol engines) is it not the same thing for diesels?

I do twice a year with normal driving, minimum, more when big trips are mixed in, regardless of their claims.

Originally Posted by G.man

Thanks.

Since delvac 1 can go longer between drains, does that in any way mean protects better or is that basically they protect the same just one does it for a longer time period?

How much difference would we be talking here in terms of "one can go further between changes"?

I spoke to M1 and they told me the ESP M1 on trucks get changed every 30-40,000 km.

I mean from my regular 10k per oil service on my regular car, 40k is HUGE difference.

Why would a person not want a very long drain interval? I mean it only means less cost on maintenence the further it goes...

I was always under the impression that full synthetics would always in the long run be better than mineral based oils (for petrol engines) is it not the same thing for diesels?

Hahaha, 30-40k for the full syn?
Try 90-110,000km between changes.
Trucks do 30,000km on mineral oil.

Several factors at play here.
1. Sump capacities are 25+ litres.
2. Makeup oil over that time replenishes the additive package.
3. Interstate line haul is relatively kind to oil compared to local delivery as temps and loads are relatively consistent.

Full syn oil oxidises at a slower rate than a mineral counterpart, ultimate wear protection may or may not be at a lower rate, it all comes down to the additive package and its suitability for a particular engine.

I have a lot of time for Delvac 1.
The old CI-4 version was able to go 20,000km easily in my partners TD42T Patrol with better wear metal numbers at that distance than a full mineral Fuchs oil at 5,000km, which was a very good oil in it's own right.
It also stopped the Tdi in the Defender from breaking the crank or spinning a bearing when the big ends delaminated.
A lot of late '98 Tdi's had crank/big ends fail catastrophically due to faulty big ends.
A quick linish of one journal in situ, slapped a new set of big ends in (clearances were spot on) and that engine is still fine seven years later.

I haven't run that oil for over six years, but it is very good.