in order to find out how often to change your oil you can look at the viccosity rating ... 20w50 is alright i would change my oil say every 5000 km's but if you have say 0w30 or 10w40 you would change it more often due to its viscosity being lower .... eg the oil thins out much more at higher temps thus reducing the effectivness of the fluid

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Hmmmmm..... Jennifer Garner

But we wouldn't be using these in our mini would we now?...

Those Oil's would also be synthetic and would easily last 5000k's....

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Aint that too thin?

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Lillee - 1969 Morris Mini K

The ratings such as SF, SG, SL, SJ etc etc are all ratings as to the type of oil. If I can recall correctly they are generally indicative of the age of an oils forumalation.

Example....Take 2 oils which are 10W/40...An SL 10W/40 is a newer formulation in terms of additives etc compared to SF 10W/40...

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[Maverick] 1971 Mini K

An SL would be way more expensive than an SF, too!

People say that the later oils carry on from the last one, which means you can use newer oils in older engines, but with the Mini using the same oil in the gearbox as the engine, this may not apply. I always use an SF or SG, which is usually the castrol formula R. The pentrite HPR30 may not be the perfect oil, as I think it's an SJ, but I doubt there's a problem. I'd just choose that formula R over the HPR30.

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i was running a bit low this month on oil in my vr commodore (1995), i used a shell SG 20w50 and its going great, you can mix synthetic and mineral based oil together it wount react in a nasty way .... also if you've been running your engine on mineral based oils, and then decide tou want to change to synthetic, it could be a costly exercise, ....
When a car has been running on a mineral based oil for some time (say its entire life) the oil creates a coating on the internals of the engine, and as seals wear the coating helps seal the seals lol. + when changing from a synthetic to a mineral a flushing oil should be used.... so if changing from a mineral to a synthetic, and you used the flushing agent all the baked on crud (microns think.... dont get too anxious) is set free to clog up your oil filter and play havoc with your engine

so remember older engines should just stick with mineral based oils.... they worked then so why go ****ing with it for minimal gain, if any

my piece on synthetic and mineral based oils

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Hmmmmm..... Jennifer Garner

Molina,
I change my oil at 1500 miles because:
1. I used to change it every 1,000 miles once, way back, but oil is getting more expensive..
2. The factory used to recommend 3000 miles,, but by then it is black and had the crap beat out of it by the gearbox gears.
3. I've seen how Minis sludge up inside if it's left in too long.

Regular oil and filter changes (I do filter at 3,000 miles) is cheap insurance for a good engine, IMO. Even more important if it's a modified engine which gets thrashed.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I've always had a 'thing' for synthetic oils. In my 'normal' cars i wouldn't use anything but synthetic. i recently sold my EF fairmont - used synthetic (mostly caltex havoline) for the 140000km that I owned it and the oil was still clean after every 10000km when i changed it - even with 220000km on the clock. Anyway after hearing all the for's and against's for synthetic in a mini i decided the only way to be sure is to try it. I used Redline oil ($180 for 5.5L). Going fine so far - only been in there a couple of weeks so I'll have to wait and see how it goes...
The guy where I bought the oil said he uses it in his race car and doesn't change it for the whole season, and in his road cars he changes it every 40000km and its still fine... I don't think i'll leave it quite that long in the mini

I suppose the crazy part is that even if best case scenario is true and my engine lasts twice as long running on synthetic oil, the oil will probably cost me more than a rebuild would have oh well... whatever it takes to satisfy my curiosity...

worst case scenario? my gearbox will blow up and cost me a fortune and next time I'll listen to the experts Are there any symptoms I should look out for that the oil is creating gearbox problems, or would it just die?

Geoff,
I've heard it can affect how well the synchros work.. (or rather don't) so watch for that. Graham in aus used to race Mini Se7ens in UK with synthetic and he told me this.

As for the rest, layshafts are toasted anyway (mostly) when stripped so I can't see it being worse.
No, I'm not about to try it, I'll let you do the R&D..

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I read the R&D article on the Mini Spares heavy duty diff pin done by Keith Calver and he says synthetic oils (the ones with detergent additives) makes the diff pin wear really fast, like 5000 miles fast

Good mineral oil for me thanks! once you've done your R&D on synthetic, let me know too

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Lillee - 1969 Morris Mini K

Actually let me tell you some R&D I've done in my car. When I first bought my car I put in any old crap I had and that was Shell Helix 20/50 synthetic. The gearbox ran like a bucket of bolts, synchros crunched, it was just BAD!

Then I learnt that it has to be mineral, so I changed to Penrite HPR30 and never looked back since. Dunno if this is anything to go by but I am not going to try that again, that's for sure!

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Lillee - 1969 Morris Mini K

I afgree with the Doc, the old GP50 is great stuff, i run it in my Cooper S which get's driven hard in motorkhana's & on the road. I change it twice a year. My Galant VR4 has 96,000 klm on it and has a oil & filter change every 5,000 k's with Mobil 1 the engine is still as new, then i would put the old Mobil 1 into my old 1100 motored clubman i used for club motorsport, it ran fine on the Mobil 1 & the gearbox is still good.

Doogie

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I won Hay once, here's the pic to prove it..


Hay, it's not about the car, it's not about the venue, it's about the people that come here. Peter Dwyer, Mayor of Hay NSW.

I thought i'd drag this thread up again since i've found out what oil the mechanic has been putting in my mini... it's a motorbike oil... Castrol ACTIV 4T (the one for four strokes, obviously).

I don't think i've seen anyone suggest using this type. I am pretty sure that the guys at Mini Spares and Repairs know their crap so why is it that it would be different to all the suggestions on this forum?

Reading between the lines, i would assume that motorbike oil is being used because the mini shares the same oil for gearbox and motor just like motorbikes.

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- Simon -

for a fresh motor, go for good new quality oil, like magn atec, mobil 1 fully synthetic,

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ausmini member 195

71K 'Kaye', KAZZ69's work in progress
66 panelvan, going no where fast...
71 MS75 toyota crown COUPE yes A COUPE!
76 ra23 celica wid 1ggte, GT3071r, 13.5@106mph with alot of spinin....

wheels keep on turnin!

Both those are pretty bad for a mini..

As for the bike stuff, i suppose it could be OK, being made for bike gearboxes and stuff, it is 20w50 as well..couldn't find anywhere that said it is..

Castrol Formula R is the best stuff though, it even says it's good to use in cars that share the gearbox.

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