Page 5 of 6

Posted: Sat Jan 21, 2012 7:45 pm
by ged
This may be of interest.

http://www.cadillacforums.com/forums/no ... dp-gm.html

Regards Ged

Posted: Sun Jan 22, 2012 12:15 am
by DaveEFI
ged wrote:This may be of interest.

http://www.cadillacforums.com/forums/no ... dp-gm.html

Regards Ged
Certainly is. :D

Posted: Mon Jan 23, 2012 8:30 pm
by ChrisJC
Doesn't leave me any the wiser though!

Chris.

Posted: Mon Jan 23, 2012 10:20 pm
by ged
Hi Chris,
I know what you mean. I've been searching for a definitive answer for a while as to what is the right oil or a safe alternative that I can buy off the shelf with ease. Going through a lot of gumph about US V8 recommendations (In fact any engine that uses flat tappets) & trying to sort through those in the know & those who think they know is getting pretty tiresome.

It seems both side's can put up decent arguments for which oil they favour (latest API standards as opposed to earlier higher ZDDP ). Also to use additives or not.

Regards Ged

Posted: Wed Apr 11, 2012 2:47 pm
by jan_rrc39v8
Since i got my RRC i did not change the oil/filter yet but i did have to top it up every now and then. I used 10W40 for this since i had it standing around already. This turned out not to be a good idea.

When the engine was totally warmed up (highway runs) the oil pressure warning light started flickering (when idling and trundling in traffic jams)

After this i decided no more 10W40 top-ups. I started using 20W50.
No more oil light flickering.

The block uses about 1L every 2500km.
Is this typical? or high? (no blue smoke visible, but then again, it has cats... ) The past 2 months i have used the car on fast long distances (70-80mph). Most likely a lot heavier use then the previous owner did. I believe he only used the car on medium/short local trips.

Posted: Wed Apr 11, 2012 3:35 pm
by DaveEFI
My SD1 EFI has always had 10/40 as that's the recommended oil. Oil light never flickers even at the slower than spec idle (600rpm)

I suppose it's possible your switch is faulty? Although they normally fail so the light doesn't come on ever, or leak.

Posted: Mon Dec 30, 2013 9:31 pm
by Dixie6789
I have been using Granville 20/50 oil for 3 yrs now in my 3.5 Vitesse. Always stick a can of Wynns in it, and get 50 psi on cold start up and 30 when up to 80 deg C.

When I called the company who supplies it, they said it had all the additives required. And at £15 for 4 ltrs I change it every 2000 miles or once a yr.

http://www.ebay.co.uk/itm/GRANVILLE-PRE ... 53e7b1a78c

Seems to work for me.

But may buy some other stuff for my re-built 4.6

Re: Engine Oils. which ones???

Posted: Thu Jan 04, 2018 12:10 pm
by gd302
How many of you guys still stick to the tried and tested 20/50 in a serp engine with crank driven pump?
I see some go for a 10/40 semi without issue and others a racing 20/50.
Some of the ester based oils look good but are very expensive, but I suppose you get what you pay for.
It seems to be a question that will never get answered properly!
100 quid once a year does not seem unreasonable to me in a car used now and again with standing in the garage.
Your thoughts would be good.

https://www.opieoils.co.uk/p-68898-fuch ... e-oil.aspx

Re: Engine Oils. which ones???

Posted: Thu Jan 04, 2018 12:15 pm
by Coops
What I use and have done for many years even. In my current engine
20170201_183618.jpg
20170201_183618.jpg (667.12 KiB) Viewed 7264 times

Re: Engine Oils. which ones???

Posted: Thu Jan 04, 2018 3:43 pm
by gd302
Plenty of zinc for the cam.
Valvoline racing 20/50 seems to be another well thought of product.

Re: Engine Oils. which ones???

Posted: Sat Feb 15, 2020 3:54 pm
by richardpope50
Well I thought it worth asking again!

Have just browsed the internet including oil suppliers and just about every combination of 20/50w to semi to fully synthetic oil is recommended.

My 1997 TVR Griffiths 500 engine had a factory sticker saying to use Mobile 1 but that is now a fully synthetic oil but probably was not then. I started using that but switched to a 10/40 semi (from local motor factors) as I thought it nearer the original grade.

Whilst all seems fine, my engine is laid up every winter and I hate the clatter when I first start it in April when it seems ages before I get oil pressure. I just hope a film of oil is left on the bearings from the year before. I also only do a few thousand miles a year and change the oil and filter every year too.

Internet petrolheads seem to use Valvoline VR1 20/50 racing oil but others recommend Classic Oils Heritage 20/50 with higher zinc otherwise same spec as VR1 (and it's just £20). All suppliers seem to suggest 10/50 fully synthetic but is that because it is more expensive?

So, current opinion is?

Re: Engine Oils. which ones???

Posted: Sun Feb 16, 2020 10:08 am
by DaveEFI
So a crank driven oil pump seems to drain down much like the dizzy driven one?

Re: Engine Oils. which ones???

Posted: Sun Feb 16, 2020 12:04 pm
by richardpope50
DaveEFI wrote:
Sun Feb 16, 2020 10:08 am
So a crank driven oil pump seems to drain down much like the dizzy driven one?
Yes. If I remove spark plugs and crank I do not seem to get pressure up so I simply start engine and pressure does come up pretty quickly but there is still that few seconds, but always seems a long time, when one waits for the sound to change.

Re: Engine Oils. which ones???

Posted: Mon Feb 17, 2020 10:22 am
by SuperV8
richardpope50 wrote:
Sat Feb 15, 2020 3:54 pm
Well I thought it worth asking again!

Have just browsed the internet including oil suppliers and just about every combination of 20/50w to semi to fully synthetic oil is recommended.

My 1997 TVR Griffiths 500 engine had a factory sticker saying to use Mobile 1 but that is now a fully synthetic oil but probably was not then. I started using that but switched to a 10/40 semi (from local motor factors) as I thought it nearer the original grade.

Whilst all seems fine, my engine is laid up every winter and I hate the clatter when I first start it in April when it seems ages before I get oil pressure. I just hope a film of oil is left on the bearings from the year before. I also only do a few thousand miles a year and change the oil and filter every year too.

Internet petrolheads seem to use Valvoline VR1 20/50 racing oil but others recommend Classic Oils Heritage 20/50 with higher zinc otherwise same spec as VR1 (and it's just £20). All suppliers seem to suggest 10/50 fully synthetic but is that because it is more expensive?

So, current opinion is?
The trouble with this old oil debate - is no 'enthusiast' will ever be able to provide actual empirical evidence as to the 'best' oil option.
We can say without doubt a 10/40 will flow better and so provide quicker protection on start up.
I use a good quality 10/40 on my 4.6 with serp oil pump and has more than enough oil pressure when hot (i.e. its not too thin!), and minimal time for pressure build up after prolonged winter lay up.
From my understanding you only need a 20/50 with the serp/crank driven oil pump if you see excessive oil temps. My oil temps don't exceed 110C which is fine for a good full synthetic 10/40. If I was seeing a regular 120+C I would change to a 50weight - but still keep 10 for better starting protection.

Tom.

Re: Engine Oils. which ones???

Posted: Fri Feb 21, 2020 10:22 pm
by Henry-b
I use a Multigrade 15w40 Mobil 1000 in my 4.6..

No oil pressure issues and it sounds and runs really sweet..
This is the issue that plagues an engine that has been around forever, everyone seems to have their own opinion on what will work! :rofl