Engine Oil

[Glyn Ruck]

Thanks for posting that Glyn.

I found this article in this month's Motor Mechanic trade magazine that might be of interest. I was wondering if this would apply to oils claiming to reach the MB229.5 standard. Any thoughts on this Glyn?

Nigel, Earlier in this very thread I pointed out to Joe that a small company was being purposely misleading regarding claims ~ they were not approved. There are many like them. The majors can't afford to do that. They would be sued blind.

That is why I always recommend Benz approved products that can be simply checked for veracity against their global service products approval listing.

Benz protects it's customers (& the warranties they carry) by putting products through stringent testing. Duly approve or otherwise that oil, grease, coolant or whatever & publish the approvals listing. They also spot check products around the world for conformance to formulation against which these approvals were issued. Benz has done this for many decades. Their testing is so stringent that they will even reject an oil that leaves a slight stain on a plain bearing.

If the approval is correctly claimed on the package & is on the Benz approvals listing you are safe.

https://bevo.mercedes-benz.com/bevolisten/229.5_en.html

[NigelW]

Thanks Glyn, I've been looking for suitable oil to use in my engines using your advice regarding the MB299.5 spec. Please can you tell me if the MB229.51 is ok for our cars - thanks.

[Glyn Ruck]

No ~ 229.51 is not OK for our cars. It's low ash <0.8, low additive treat for passenger car diesel with Cat & particulate filter/regen unit. Diesels are rev limited by the combustion process & run mild cams.

Benz specifically placed ash clamping limits so no one could claim their (compromised) oil could meet both 229.5 & 229.51 or .52. in a single product. Thus forcing an optimised product for each application.

[jonesdl]

A question for Glyn regarding the MB 229.5 oil. Having looked at various fully synthetic engine oils for my S type 3.8 in the U.K. I cannot find an oil that is straight MB 229.5 approved only, but was looking at the Castrol Edge Fluid Titanium 5w-40 MB approved 229.31, 229.51 and 226.5. I would value your opinion please or suggest another variant number coupled with with MB 229.5 that would be suitable.
Many thanks.
Dave J.

[Glyn Ruck]

Dave ~ any oil on this listing.

https://bevo.mercedes-benz.com/bevolisten/229.5_en.html

Mercedes does not permit an oil to meet both 229.51 (passenger car diesel with particulate filter) and 229.5 ~ multigrade gasoline. They place ash clamping limits on the spec to prevent oilco's from claiming that a compromised product meets both specs. In basic terms 229.51 products are low additive treat to protect diesel emissions gear. (diesels are rev limited by the combustion process & run mild easily lubricated cams). 229.5 products are high additive treat.

Example of correct product on Amazon UK.

https://www.amazon.co.uk/Castrol-1507FE ... -7-catcorr

Clip from Benz 229.5 Approvals Listing.

Clip from Benz 229.5 Approvals listing.JPG (16.95 KiB) Viewed 2031 times

[jonesdl]

Many thanks Glyn for the information, I am in the process of changing oils throughout the car so more questions to follow.
Dave J.

[pjrjag]

Never use full Synthetic oil in these old engine, way to thin!
And you will have more change of engine leaks, the old seals are not used to that kind of oil.
Just use any 20W50 mineral oil, brand does not really matter.
These old engine engine do not mind all those modern specs, they did not even exist in those days.
I always buy bulk of 50L 20W50 for my jaguars ( XK140.XK150, S-type 3.8 )
More then 20 Years owner now, never had problems.

Regards,
Peter Jan

[cass3958]

I appreciate what you say about these engines being older but modern oils as Glyn has explained at great length have advanced and protect the engines so much better that older oils. Just because the engines are a 74 year old design does not mean they would not benefit from a modern oil. Also most of our engines and certainly mine have been rebuilt with modern materials in the bearings and pistons and piston rings so a more uptodate oil is possibly more in keeping with the materials that have been used in the rebuild.

[Glyn Ruck]

Never use full Synthetic oil in these old engine, way to thin!
And you will have more change of engine leaks, the old seals are not used to that kind of oil.
Just use any 20W50 mineral oil, brand does not really matter.
These old engine engine do not mind all those modern specs, they did not even exist in those days.
I always buy bulk of 50L 20W50 for my jaguars ( XK140.XK150, S-type 3.8 )
More then 20 Years owner now, never had problems.

Regards,
Peter Jan

Not the best way to look after your Jag engine & a 20W-50 is thicker than ever intended by Jaguar. Read this thread!

Synthetics are not too thin. These engines never need anything heavier than an SAE 40 even in the most extreme conditions. e.g an SAE 5W-40 synthetic is an SAE 40 at operating temperature & will stay in grade unlike old 20W-50's that have no shear stability.

Jaguar's design engineers would have loved to have modern technology lubricants available to them.

[Orlando St.R]

Hi folks.

I thought I would report back on this thread with my experience of using Millers 10W40 full synthetic engine oil since May 2020. Following the recommendations in this thread - and the fact that the oil specifications in the user manual/chassis plate don't specify anything higher than a 40 weight oil - I had to try it out for myself to see if a 10W40 would give me sufficient oil pressure.

s-l1600.jpg (68.36 KiB) Viewed 1343 times

On the way home from the service and oil fill, with a new filter, oil pressure just reached 40psi at 3,000rpm. Although I haven't used the car much this year, whenever it has got really hot - after heat soak - pressure does not quite reach 40psi at 3,000rpm. That said, oil pressure did not get worse over the six months I ran the car in 2020. And the engine is no noisier. But the low oil pressure worries me!

Millers are quite a respected brand in the UK and produce a wide range of oils. Here are the specs for the one I used: https://www.millersoils.co.uk/wp-conten ... 0w40-3.pdf. Note that this particular oil doesn't have any manufacturer approvals, but Millers produce plenty of other oils that do.

My conclusion is that, for whatever reason, a 40 weight oil is not sufficient to give my engine decent oil pressure. The reasons may be:

1. It gets very hot under the bonnet, particularly during heat soak, maybe because of modern fuel or maybe for some other reason(s). Coolant temperature on the gauge sits at more or less 70C, so the coolant circuit would seems to be okay.

This earlier post details what happened in 2018 when I used a mineral 20W50 which, according to the analysis at the time, fell out of grade after 500 miles in my car: http://jagstyperegister.com/forum_new/v ... 3430#p3430. Apparently the most likely reason for this is that the oil got too hot.

2. The engine was rebuilt in 2014 with a remanufactured standard oil pump. It's done 9,300 miles since then. Not sure whether this might be underperforming.

3. I'm fairly happy that the gauge is accurate. It is a new one with matching sensor from Caerbont Instruments: https://www.smiths-instruments.co.uk/jaguar. And the oil analysis in 2018 seems to suggest it tells the truth.

4. Ignition. Well, it is a possibility that the ignition is too far retarded at some points in the rev range, I guess. I am using a 123 Distributor and none of the 16 curves really get that close to the original distributor curve. Maybe I need to invest in one of the latest versions that allow you to set the curve you want.


So, my thinking is that in future, for my particular car, I will stick with a synthetic, but choose one of a higher weight - 10W50 or 10W60. It seems a cheaper/easier option that pulling the engine apart!

I'd appreciate any comments and observations.