5-30W semi-synthetic engine oil question.

[J44EAG]

I`ve just acquired 15 litres of DIESEL engine oil.

My question is would this be suitable for a V8 PETROL engine?

I`ve often heard it said that their is no difference between petrol and diesel engine oil. Can anyone confirm?

Mike

[Brakebuster]

Very simply the three main areas are:

Higher dispersancy to deal with higher levels of soot
Higher detergency levels to minimise depositing on components and as a result a higher TBN which will minimise the risk of Sulphuric Acid formation from diesel dilution.
Diesel engine oils, as compared to petrol oils, do not have very good low temperature sludge formation resistance.

Diesel oils are useable in petrol engines, but if signs of low temperature sludge formation are seen, then switch back.

Petrol engine oils are not suitable for diesel engines in the long term because of the lack of detergency/dispersancy predominant in a diesel, and also a lack of high temp sludge formation.

I lifted this from another site , seems to make a lot of sense , but, is it worth damaging your engine for £60 worth of oil ??

BB

[J44EAG]

Good clarification, Vince. Thanks very much.

Anyone near Portsmouth need 15litres of diesel semi-synthetic at a knock down price!?

Mike

[jeff1954]

Hi Guys
My 2.7D Ltr S Type uses the the same spec 5-30W semi synthetic oil as the wife's petrol Astra and has done for the last 4 years of my ownership The oil is changed once a year regardless of milage (normally 4-5000 miles with no issues.

Jeff

[J44EAG]

Fair comment, Jeff and very sensible.

See recent X-type Forum postings on suitable diesel oils for DPF equipped vehicles. It is essential that DPF cars receive the correct DPF compatible engine oil at service intervals. I note that some of the diesel oil I acquired is strongly marked "DPF". Ray Searles post on the X-type Forum explains the reasons.

Mike

[jeff1954]

Good point Mike. My car is pre DPF thank goodness as most of my journey's are short ones.

Hope you are keeping well.
Jeff

[latebreaker]

I use the recommended oil from the manual.
I managed to pick up 8 litres of Castrol to the spec below for around £39 from Amazon, with free P&P!
This oil was given to my independent when I had her serviced a few weeks ago. It was actually cheaper than the semi-syn oil he used last year.

Here's what the manual states:

Oil specification – Petrol engine
An oil of 5W–30 viscosity meeting Jaguar
specification WSS M2C913 – A or B is
preferred. Where this is not possible, oil
meeting API SJ/EC and ACEA A1 98 or A3
98 may be used.

Oil specification – Diesel engine
An oil of 5W–30 viscosity meeting Jaguar
specification WSS M2C913 – B must be
used in all vehicles with a diesel engine.

For top-up purposes only, where the
WSS M2C913 - B specification cannot be
found, ACEA B1 or ACEA B3 specification
oils may be used.

Krish