Good morning everyone,

I would now also like to use semi- synthetic oil.
Am I doing something wrong with the oil? It's on sale currently: Mobil Super 2000 X1 10W-40
The oil is also said to be good for older engines...
I definitely don't want to make a mistake, as the engine is currently running perfectly. But I can't find out what is currently being used. That's why I'm replacing it completely.

Thank you!
 
Thanks.
I have one more question: The amount of oil - I've read so much now and there are 2 statements:
4.87 litres or 6.7 litres of oil are needed?
 
Frank_38 said:
Good morning everyone,

I would now also like to use semi- synthetic oil.
Am I doing something wrong with the oil? It's on sale currently: Mobil Super 2000 X1 10W-40
The oil is also said to be good for older engines...
I definitely don't want to make a mistake, as the engine is currently running perfectly. But I can't find out what is currently being used. That's why I'm replacing it completely.

Thank you!
Click to expand...
Similar to what I am using but mine are diesels..
 
Frank_38 said:
Good morning everyone,

I would now also like to use semi- synthetic oil.
Am I doing something wrong with the oil? It's on sale currently: Mobil Super 2000 X1 10W-40
The oil is also said to be good for older engines...
I definitely don't want to make a mistake, as the engine is currently running perfectly. But I can't find out what is currently being used. That's why I'm replacing it completely.

Thank you!
Click to expand...

Doesn't matter if semi-synthetic or fully synthetic. Shell always used to have the best oils. Their additives seemed to be very good. Whether this is still the case I am unsure. Some people like @Henry_b recommend an oil high in ZDDP or something like that. Sounds plausible.

I do oil changes every 5k miles.
 
Grrrrrr said:
Doesn't matter if semi-synthetic or fully synthetic. Shell always used to have the best oils. Their additives seemed to be very good. Whether this is still the case I am unsure. Some people like @Henry_b recommend an oil high in ZDDP or something like that. Sounds plausible.

I do oil changes every 5k miles.
Click to expand...
I'll push zddp too. It was only removed for emissions purposes! It helps massively with the cams/flat tappet lifters.
It's for this reason i don't recommend fully synthetic. It won't do the cams/lifters any good long term
I always used valvoline 20/50 because it's a more appropriate oil for the v8 and has zddp.
10/40 oils, again, were only introduced for emissions purposes. Not because they were better for the engine
 
kermit_rr said:
I'll push zddp too. It was only removed for emissions purposes! It helps massively with the cams/flat tappet lifters.
It's for this reason i don't recommend fully synthetic. It won't do the cams/lifters any good long term
I always used valvoline 20/50 because it's a more appropriate oil for the v8 and has zddp.
10/40 oils, again, were only introduced for emissions purposes. Not because they were better for the engine
Click to expand...

Have to admit we put heritage 20/50 in that 4.0 litre we fixed and it ran really well on it.
 
ok, the zddp thing is new to me.
But my favourite (because of the price) would be Mobil Super 2000 X1 10W-40 also seems to have zddp.

here is an example:
www.opieoils.co.uk

Mobil Super 2000 X1 10w-40 Premium Semi Synthetic Engine Oil

The UK's largest independent supplier of automotive oils, fluid and parts. We've products to suit any vehicle, from full blown Race / Track weapons, to Daily Drivers looking to save money. Plus FREE expert advice & recommendations - OPIE KNOW OILS
www.opieoils.co.uk

what do you think? am i making a mistake?

All at my own risk, of course!
 
I don't expect any oil marketed for general use today will have zddp in it. It was removed because it could reduce the life and efficiency of a catalytic converter, but it's critical in flat tappet engines.
Some people will say that's utter rubbish, but these are usually the same people that say fully synthetic oil is fine for running in an engine rebuild.
In my case, i could get 20/50 mineral oil cheaper than any more modern stuff so i went with that. It also had high zddp so it was a no brainer. The cams on these engines are a weak spot so anything that helps stop wear can't be a bad thing
 
I can't get hold of the valvoline oils - they are not supplied.
I use the one from mobile (Mobil Super 2000 X1 ). I mean it's semi-synthetic and fulfils the standard and is currently the cheapest for me.
I'm going to change all the oils now, including the differential and transfer case.
Differential is: 1.6 litre gear oil 75w90?
Transfer: 2.0 litre ATF dexron 3 (automatic)?

Thank you!
 
Screenshot 2025-05-05 at 11.44.10.png
 
Thanks!
the mobil oil i wanted to buy does not match the specifications even though it is recommended on the mobil website. what's the point?

NO SG or SH
NO ACEA A2:96

hmmmm...
 
I think you're over thinking this. Any oil you can buy today will exceed ACEA A2:96. As the numbers go up the old spec is superceeded. Your Mobil Super is A3.... one better than A2. So long as it's 10w/40 you'll be fine. It's an ancient V8 from the stone age. Any oil with the correct viscocity will be perfect.

Further reading if you want here...

www.opieoils.co.uk

ACEA Car Engine Oil Explained | Petrol & Diesel Motor Oil

The UK's largest independent supplier of automotive oils, fluid and parts. We've products to suit any vehicle, from full blown Race / Track weapons, to Daily Drivers looking to save money. Plus FREE expert advice & recommendations - OPIE KNOW OILS
www.opieoils.co.uk
 
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