81 replies to this topic

[Tamworthbay]

If I had a penny for every time this topic comes up... ;)

You would have £4.27

[MRA]

yes but everyone here is forgetting so much it's unreal....

Firstly Rover manufacturing procedures have changed over the years, not ONE metro was ever manufactured to use 20w50, Metro's and later Mini's where all designed and tested to use 10w40 I never use 20/50 and haven't done since the early 80's

The interesting thing here is that Rover had Warranty claims to look after, so if 20w50 was better then they would have used it !

Also if you run a later Automatic and you install 20w50, then expect a very large bill in the near future, its 10w40 or the scrap yard...

[Smee2012]

So which one is better 20w50 ,15w40 or 10w40 :)

[Cooperman]

You can all use what you want. I know that Rover machining was not as good as the earlier BMC machining and their quality control was, quite simply, dreadful.
The basic gearbox design never changed and that is the real issue.
The interchangeability of cranks, cams, oil pumps, gearboxes, all shows that there were no engineering changes over the years.
Rover probably went to a thinner grade oil because their engineers were, bluntly, stupid. They bere so stupid that they mixed metric and imperial threads on the braking system. Quite simply, the good engineers left and went to work for 'proper' manufacturers, and those left were, in the main, well you can guess!
An A-series engine is and always will be a 60 year old design.
Autos are another issue entirely.
This old 'what oil' thread just keeps on appearing.
The true answer is a 20w50 mineral oil with a high ZDDP level.

[mini-luke]

yes but everyone here is forgetting so much it's unreal....

Firstly Rover manufacturing procedures have changed over the years, not ONE metro was ever manufactured to use 20w50, Metro's and later Mini's where all designed and tested to use 10w40 I never use 20/50 and haven't done since the early 80's

The interesting thing here is that Rover had Warranty claims to look after, so if 20w50 was better then they would have used it !

Also if you run a later Automatic and you install 20w50, then expect a very large bill in the near future, its 10w40 or the scrap yard...

Were tolerances different on the later engines Rover intended to be ran on 10/40? I know Tim Harber uses 10/40, his reasoning being that Rover said so which was good enough for me.

[Cooperman]

On later engines the tolerances were even worse than they were in 1955!
Everyone can use whatever they like. Having had the (mis)fortune to have been a sub-contractor to Austin-Rover in the 70's & 80's I can just say that they were an absolute disaster.
The worst A-series engines were the last MPI units - I even had one where the main bearing housings, as delivered, were undersize and knocked out the bearings very quickly. Had to get the mains line-honed to correct it.
In the UK, the best oil for a Mini, with a combined engine & gearbox, is a 20w50 MINERAL OIL WITH A HIGH ZDDP LEVEL!

[Mrpeanut]

Which 20/50's have the required levels of zddp?

[Cooperman]

Millers, Penrite, Valvoline VR1, to name but 3.
Castrol Classic 20w50 is reputed to be good and some use Halfords Classic 20w50.
Do not use the muck as sold by some of the cheapie retail outlets.

[mini-luke]

Millers make a Mini specific oil that's got EP additives for the gearbox, only £4 more than Halfords oil

http://www.opieoils....t-mini-oil.aspx

[Mrpeanut]

^^^ . Cheers cooperman. Did I read that the millers mini oil has a lower zddp than one of their other oils?

I've used the halfords and didn't think much of it. Thinned out quickly and the gearchange wasn't great. Now running Morris golden film and the car goes well with better gear changes. I've no idea about its zddp level - what should we be looking for as a minimum?

[jaydee]

Millers, Penrite, Valvoline VR1, to name but 3.
Castrol Classic 20w50 is reputed to be good and some use Halfords Classic 20w50.
Do not use the muck as sold by some of the cheapie retail outlets.

No, avoid castrol classic XL and halfords (or comma classic) if you want high ZDDP since they've changed the spec to 800 ppm which is even lower than ANY reputable 10w40 synth oil.
If you want cheap, comma SONIC has a lot of zddp (even too much if you aks me)

[jaydee]

Millers got about 1400 ppm and its good, the company provide a good service too.

[Cooperman]

I use Valvoline VR1 in the 'S' with SC gears and 11.1:1 CR. On other Minis I use Castrol or similar, but I do change it about every 1500 miles.
I did once try a Shell 10x40 synthetic on a rally and it cost me about £700 to rebuild the engine & gearbox afterwards!

[MRA]

When the first "what oil to use" was posted on this forum or others it was all to do with viscosity and which was best and why, now its suddenly become ZDDP the latest fad.....

Funnily enough ZDDP can be found in various grades of oil, however don't make the mistake of thinking that because it has a certain value of ZDDP in the oil its a good oil, there are a lot of poor oils that contain high levels of ZDDP

However since the 70's and 80's a lot has changed, bearing material and manufacturing techniques have improved massively, and to say that a whole powertrain design and development team are "bluntly stupid" is very sad, a team is not one person, the normal powertrain team size for such a company would be 100+ depending on how many combinations there are, it is a derived decision, gained from years of testing and retesting.

The reason for mixed threads is to avoid safety issues, imagine your mini had 3/8" unf fittings and you went to get a new master cylinder which to please a minority had metric threads to suit later vehicles, well as the metric would be M10 and the imperial 3/8" (9.525mm) it will fit, but not very well and when it lets go I wouldn't want to be in that design team ...

[Cooperman]

Anyone who had dealings with Austin-Rover and Rover knows just how bad they really were. They were quite bluntly, totally incompetent in engineering, sales and marketing.
To mix metric and imperial threads in a braking system with almost identical sizes of thread is, quite bluntly, stupid. Rover engineers did that.
The manufacturing tolerances were not good and were better in the 60's from BMC. Rover had no money to spend on accurate machining or good quality control.
I know, for a fact, that they used whatever cams they happened to have in stock because the cam manufacturers declined to deliver orders as they had not been paid. Other sub-contractors did the same. I stopped dealing with them because they took a minimum of 180 days to pay my correctly sent bills. The sub-contractors who continued to supply them were few and of generally poor quality themselves. A friend who was a senior person in Engineering Procurement there admitted it to me privately.
The MPI's were the worst Minis ever in terms of engineering quality as Rover had no interest or money for continual improvement.
The powertrain design & dev't team had no budget for Mini development and very little was done. In fact, there was not really any development team for the Mini from about 1990 onwards, except for the engineering necessary to meet emissions and safety mandated requirements.
The gearbox is in effect identical with the original with only minor changes.
Manufacturing tolerances did not alter or improve. In fact they got worse. Warranty issues were greater with the Mini than any other Rover model.
Rover wanted to stop production of the Mini much sooner and remove the liability to them. Only the high level of Jap sales kept it going. All the engineering effort went into the Rover 200, 400 and 600 series and, later the 25, 45 and 75.
And that, friends, is why we have to spend so much time restoring our classic Minis. In fact, we are just completing the build programme!