Castrol Gtx - which one???

[Pastapesto]

Happy new year to you all

The time has come to do an oil change & so I just wanted to see if anyone has tried either Castol gtx high mileage (15/40) which I have just bought, or Gtx (standard one) (10/40) , Castrol Magnatec or the Castrol classic which is 20/50. I want to use it in my Sprint engine that has some very small leaks here & there (surely a first) & runs pretty much as normal other than that. It has done about 6000 miles since its last rebuild and was put together by one of the specialists a few years ago.
By the way, not particularly a Castrol fan, just what I remember from the good old days (if they ever really existed). In the past I have used Mobil 1 in a +2 I had & that seemed fine, but am a little worried that using a synthetic might create more leaks than I already have. With this engine I wanted to stick with a good normal mineral oil (it previusly had Motorcraft 20/50 from the PO), I know there are some very good other brands out there but I just really wanted to stick with Castrol if possible. The Castrol Gtx High mileage has the additive that is supposed to soften & swell slightly the seals & help to slow down or stop the leaks a little bit. Oh, one other thing, I do not do a lot of miles every year so I just really want a good oil that I will be changing long before it really gets dirty & something that will protect all the important bits.
Anyone know a lot more than obviously I do about this subject?

Your knowledge & help would be appreciated

Regards

Adam

[cliveyboy]

Adam
IIRC Brian Buckland visited Castrol and they recommended magnatec for cars that do not do many miles as it has better clinging properties so provides better start up protection if the car had been stood for a while. Otherwise they said normal GTX would be fine for cars that get used and oil changed regularly.

Clive

[pamitchell]

Here in the USA, Castrol GTX 20-50 is popular and has the necessary zinc additive for flat tappet engines. There are several write-ups on oils with the proper additives. Valvoline VR-1 is another recommended brand.
Phil

[264889socal]

I have been using 20-50 with good results. However, got my March issue of Street Rodder magazine last night and it has a good article on oils and problems with the new low zinc content. Another source of good information.

Rob

[Ronter]

Hi Adam,
I spoke to a spokeswoman from Castrol a few years ago about this after using GTX for a while. She actually recommended I use Duckhams 20/50! I used this for a few years, buying it from Asda for peanuts, but then they stopped selling it! I was then advised to use Valvoline VR1 20/50. This oil is " unburstable " and contains all the Zddp's that most other oils don't. ( These are the lubricants that modern catylist engines don't like and they keep old engines happy, looking after the cams mostly ). It's not too expensive either ( compared to synthetic ). Oil still leaks out, but I'm happy;I'd rather clean my drive again than take the engine out. (Again.)

[fluff]

All oils have their plus points, but I always found, in lower mileage engines like yours that Castrol (all variations) tended to emulsify (small ammounts of mayonaise round oil filler) more than say Duckhams for example. This was particularly true if the mileage was mainly done in shorter bursts, I now use Valvoline VR1 exclusively in two Twin-cams one dead standard Big valve in a +2 and one nicely hotted up Fast Road engine. It contains all the good bits that others have mentioned and is more readily available than you think, Southern Motor Factors for example keep it in stock.

[zarelan]

I also put Valvoline VR1 20W50 in my Sprint. High quality mineral oil at a very reasonable price. Much better in my opinion that the Magnatec and GTX ones from Castrol. I toyed with the idea of switching to syntethic, but then I tried Valvoline VR1 after reading some posts in this forum. I was impressed with it's ability to keep higher pressure when hot and it eliminated the top end rattle I used to hear with Magnatec 15w40. I'm now sticking to Valvoline. All the major online motorsport suppliers stock it. I get it from Merlin Motorsports.

--Antonio

[hatman]

Hi Adam,
I spoke to a spokeswoman from Castrol a few years ago about this after using GTX for a while. She actually recommended I use Duckhams 20/50!

Perhaps not so surprising as Duckhams is owned by Castrol.

[steveww]

I am currently using Millers Classic Sport 20/50 for my twinc. See http://www.millersoils.net/index2.html

[Dag-Henning]

- quite a few racing-people I have been talking to speek highly of the Miller products.... - for some reason I do not know.....I only wish we could agree to the three items of no discussion on this forum ; women, politics and lubricants......

Dag

[garyeanderson]

- quite a few racing-people I have been talking to speek highly of the Miller products.... - for some reason I do not know.....I only wish we could agree to the three items of no discussion on this forum ; women, politics and lubricants......

Dag

Hi Dag

I think we all agree the first two will take all your money and give it to someone else, the last one you can not afford (see the first two)

Gary

[Alasdair]

Any 15/40 Diesel CJ4 or equivalent. Shell Rotella for one.

I have been using this in all my cars for years.