Section : Oil and Filters

10W40?

Posted By : Mark Telkman, 15-Dec-2004, 05:21pm

Clearing out the garage a bit this afternoon, I decided to throw out some of old oil, the majority of which were little remnants at the bottoms of bottles, whereas I still have a gallon and a half of Castrol GTX Magnatec (semi synth?) 10W40. Do you reckon I could safely run this in my MkIV over the winter until I get around to another oil change? I'm not quite sure what people would recommend as far as synthetic/mineral oils go, or what the Spitfires run best with, aside from the 20W/50 guide in various manuals. I guess I can always keep the 10W40 hanging around to flush the engine through, or for topping up the dashpot, though it'll take a while to use it all up that way.)

Any thoughts on where the cheapest places to pick up Duckhams oil (or other suitable manufacturer's) nowadays are much appreciated - local petrol stations and motor factors all seem to want &163;20+ for a gallon.

Followups :

10W40?

Posted By : Colin Wake, 15-Dec-2004, 07:15pm

Shouldn't be a problem running the 10/40. Especially over the winter.

I have been using a Millers 20/50 semi synthetic (Classic sport), and have been very impressed.

I got it for &163;18 a gallon, but had to buy 4 gallons. I have subsequently sold on a gallon, used 2 gallons in 2 cars and got a gallon left or topping up, Haven't had to top up yet!

Colin
10W40?

Posted By : William Davies, 15-Dec-2004, 08:31pm

Hi Mark,
I wouldn't be too worried about that viscocity over the winter, but my experiences of Magnatec have not been good. I was aware of it's reputation for attacking plastic components, but as I had some here which had cost nothing, I used it in our VW Passat. After using this stuff for 2 oil changes, the plastic dipstick tube had become brittle and snapped, and the oil pressure switch ruptured it's diaphragm, spraying oil copiously around the engine bay. Both instances are no more than anecdotal evidence, but they match perfectly with what I had previously heard about Magnatec,
Cheers,
Bill.
- 10W40?
  
  Posted By : Mark Telkman, 15-Dec-2004, 08:42pm
  
  Its not something I've ever bought myself - more through the high cost than hearing horror stories about it. I had an old banger about a year ago which I got very much on the cheap, as it was leaking and burning oil at a ridiculous rate. As part of the bartering, I got a load of stop smoke and three bottles of oil thrown in, as the guy had loads about for using the car himself (quite why he didn't have something cheaper, I'm not sure...). I ran a couple of bottles of my own and then two of the magnatec through myself before having it scrapped. This was all I had left, so thought I might as well see if people thought I could get away with using it. I guess I'll run it on this for a couple of months and see how she gets on
  - 10W40?
    
    Posted By : Van Hamlin, 15-Dec-2004, 09:51pm
    
    There's a few people in the 2000 register using very thin semi-synthetic oils. My 2.5 PI has semi-synthetic 10W40 (or maybe something even thinner) in it, left over from previous owner. It doesn't leak, but when I accidentally put Castrol GTX mineral 10W40 in the GT6 instead of my usual Castrol GTX mineral 15W40 it pissed out about 2 pints in 250 miles of hard driving.
    
    So really some people are happy with it but I wouldn't use it if you have any oil leaks!
    
    Also I think people advise against mixing synthetic and mineral oils (for example when you top up).
    
    Van
10W40?

Posted By : Ian Palmerino, 16-Dec-2004, 08:12am

Mark
my local car accessorie shop sells duckams classic 20/50 for &163;7.99
i bought some last weekend.

Ian