What Oil

[helicopterdcr]

I'm in the throes of my first engine oil and filter change. It's a standard 13/60 engine with 60k miles on the clock (and in good nick). Should I go for a semi-synthetic, ordinary 10-40 or what? Let's see how many opinions there are - or does everyone agree?

[brucy]

I had duckhams 20/50 in mine before. Going to try the halfords stuff next (20/50 classic)   because it's easier for me to get hold of

[heraldcoupe]

Stick with a decent 20w50 and you won't go far wrong.
Cheers,
Bill.

[Deleted User]

Bog standard mineral based 20W50. Thinner oil will leak out of the seals (they're not designed for thin stuff). Just make sure that you change it regularly, 3000 mile drain intervals is the optimum, 5000 miles will still be OK. If you don't do a lot of driving each year then change it annually.

You won't get any benefit from a semi synthetic (in fact I've had trouble with oil seals with some semi synthetics), in the UK it's difficult to find 20W50 semi synthetic anyway. Make sure that any oil you buy has a SAE spec on the side, the ones without one will be recycled (ok for oil burners but not a good engine!).

There is some talk that SAE SM grade oil is not a good idea for push rod engines, but this will be fully synthetic (and very expensive).

Always change your oil filter when you change the oil.

BTW I used to work for an oil company, although my field is metalworking lubricants I have spent some time in engine oil development.

[herald948]

Add me to those who endorse 20W-50 "traditional" oil. I've used mostly Castrol GTX 20W-50 in my Herald for almost 30,000 miles now (all the mileage I've actually put on the car since buying it in 2002), except for the most recent change when I put in Castrol's "high-mileage GTX 10W-40. Frankly, though, I'm not as happy with that and have some 20W-50 ready for the next (hopefully soon) oil/filter change.

[lordleonusa]

See

http://www.lnengineering.com/oil.html

Best Oil site on the web, and there are a LOT.

L

[helicopterdcr]

Thanks for the swift feedback! I never really know about these things. I'll go for the decent 20/50 options (and spend a lot of time reading LLusa's recommended site).
As an aside, I race a 500cc pushrod Velocette; it is regularly stripped down - after most meetings in fact. I run it on a 10/40 fully synthetic, and after about 400 race miles in the last couple of seasons, there's nothing to complain about in terms of wear; it just doesn't smell as good as Castrol R!
Cheers, Dave

[Smallfry]

There is absolutely nothing wrong with using semi or fully synthetic oils. Without a doubt SOME do offer better protection than any mineral based oil. Unfortunately, what IS a problem is the use of inappropriate grades !

Seen it so many times, nob in the shop says its better, so sells you 0w-30 or something similar, which is fine and dandy in a modern, wide bearing, close tolerance engine, but no use at all in an old design...........even in good condition. You will get loads of flow, but little pressure.

What you want is 20W-50 of a graded type. SD up to SH or ACEA A2 and A3. If you can get it, and don't mind the cost use synthetic, but to be honest, unless the engine is really highly stressed, you should use a mineral based product.

I dont think Castrol even do GTX 20W-50 any more ? I think its all 15W-40 now, which I feel is still a bit too thin for these engines.

[herald948]

Smallfry wrote:

...I dont think Castrol even do GTX 20W-50 any more ? I think its all 15W-40 now, which I feel is still a bit too thin for these engines.

I don't know about the UK, but it is still available here in the US!

[Deleted User]

I think I'm in the minority here in using synthetic multi grades. I would like to be using Mobil 1 5/40 but it's simply to expensive for my old sheds. A customer who worked for Mobil once told me that Mobil make Halfords fully synthetic, not sure of the validity of that but I have been using it successfully ever since. Having to use Triumphs all year round I find the the 'cold' part of the multigrade (the 5 bit) really useful on those winter start ups (my cars live outside). To be honest I stopped changing the oil on one of our cars when it turned 200,000 miles because I assumed it would be on it's last legs, now at 300,000 miles I'm thinking I might treat it to some fresh synthetic! In the 'old' days before synthetic I was a Castrol 20/50 man, but I got fed up with watching the viscosity tail off after a blast up the motorway, or a couple of runs at Santa Pod in the TR5. Synthetic has been a god send to me and my high mileage, and abused Triumph's.

[Deleted User]

An interesting aside. We sell Duckhams 20/50 in the shop, because that's what the punters want. We couldn't get any recently for love nor money from any of the wholesalers. When I asked one of them why he said it's because they couldn't get it from Castrol! Castrol who make/supply Duckhams simply hadn't made enough to satisfy demand and everybody sold out apparently for the best part of a month!

[heraldcoupe]

Castrol and Duckhams are both owned by BP.
Cheers,
Bill.

[Deleted User]

I wouldn't be surprised if Duckhams 20/50 brand is just Castrol 20/50 GTX brand with some green gizz thrown in by BP to make it look Duckhamsish! I still use Duckhams mineral in the fleet where an engine is coming to the end of its life, because it's handy (we sell it), and it's cheap. I wouldn't waste synthetic on a knackered engine, it's to late the damage is done.  

[heraldcoupe]

Karen's always been amused by my lifelong use of Duckhams Q, which was reputedly no more than a BP 20w50 with added green dye! This was from the days before BP owned Castrol (takeover was 2001), Q has since been rebranded.
Cheers,
Bill.

[Deleted User]

canleyclassics wrote:

I wouldn't be surprised if Duckhams 20/50 brand is just Castrol 20/50 GTX brand with some green gizz thrown in by BP to make it look Duckhamsish!

I think the word you're looking for is fluroscein, Dave  ;D

ISTR that GTX is substatially different to the BP branded stuff. After all they bought Castrol, I'm sure it wasn't JUST for the Industrial and Metalworking products......  ;D

[Deleted User]

canleyclassics wrote:

...green gizz...

Please could you avoid use of scientific terms in future? Layman's terms would be preferable.

[Ben Baxter]

canleyclassics wrote:

A customer who worked for Mobil once told me that Mobil make Halfords fully synthetic, not sure of the validity of that but I have been using it successfully ever since.

When I asked about the Halfords 20/50 Classic oil the rather knowledgable guy behind the counter (he had a TR7 and a Spitfire strangely, makes a change from the 18yr old corsa owners) told me that Mobil also made that for them.

[Deleted User]

Don't know about the BP side of the business but Castrol definately DIDN'T make oil for anyone else, so it could well be Mobil who do the Halfords stuff. That said, there's plenty of toll blenders in the UK who can knock up an engine oil. It's not that complicated, usually about five components, all of which are miscible. The difficult bit is getting the formulation right in the first place.....