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Oil? Castrol GTX?

Posted: Wed Apr 07, 2004 11:41 am
by hot66
Following on from my experiment of using Mobil1 synthetic oil in my 2.4*, I have decided to return to 'traditional' oils.

Anyone using Castrol GTX 20-50 in their 911 ?

* the experiment resulted in Mobil 1 dripping from under the right cylinder bank / valve covers :roll: , in conclusion Mobil1 in older cars does encourage leaks & is bloody expensive, lesson learned :roll: :D

Posted: Wed Apr 07, 2004 12:39 pm
by Flat 4
Mod 1, its no good for the bearings either as it to thin, danger danger danger :?

I used castrol GTX in my 12, not sure whats best for a 911.

Posted: Wed Apr 07, 2004 1:06 pm
by Lightweight_911
I've used GTX - both 20/50 & 15/40 - in 911's & 912's.

Excellent performance & cheap price means that you can afford to change it regularly.

Posted: Thu Apr 08, 2004 10:43 am
by vaughan
yeah , i'm with Andy

GTX 15/40

vaughan
73 T

Posted: Tue Sep 21, 2004 12:03 pm
by crafti
What about an engine flush? Any advice?

cheers

Posted: Tue Sep 21, 2004 12:34 pm
by hot66
well seeing this thread has raised its head again, I will update on the mobil1.

I'm actually now very happy with the Mobil1. Engine is not leaking & I'm using less oil than before . On the 1200 mile round trip to Classic Lemans including some very hard driving around the circuit, I only needed to top up the oil with 1/2 litre or so when I got back home. Oil is looking dirty though so I think its time for an oil change & I will be sticking to Mobil1

Posted: Fri Oct 01, 2004 5:26 pm
by Robster
Hi all,

if a oil is say 10W-40, then regardless of make, it should have the same viscosity! If the seals leak after putting in 'synthetic' , it is because it has more powerful cleaning agents in it, which cleans all the grunge caking your oil seals that has kept the usual oil at bay, and hey presto -you have a leak! This is also why synthetic oil looks dirty very quickly because it has cleaned the engine up and hence the dirt is now in the oil. If you have new seals in your engine, then this should be no problem. Lower the 'number' the thinner the oil, so avoid 0W-30 at all costs. 20W-50 should be fine. I use Castrol Magnetec 10W-40 in the robster mobile and it doesn't leak....

Where do you get 20W-50, oil by the way?

regards
robster

Posted: Fri Oct 01, 2004 7:45 pm
by bjmullan
I get my 20W-50 from euro car parts.

Posted: Sat Oct 02, 2004 12:31 am
by drummerboytom
Robster wrote:Hi all,


Where do you get 20W-50, oil by the way?

regards
robster
Halfords !
I think that's the new Castrol GTX for "older" engines

Posted: Sat Oct 02, 2004 2:12 pm
by crafti
drummerboytom wrote:
Robster wrote:Hi all,


Where do you get 20W-50, oil by the way?

regards
robster
Halfords !
I think that's the new Castrol GTX for "older" engines
If you mean the new Castrol High Mileage oil it's a 15W-40.
http://www.castrol.com/castrol/productd ... Id=6008842

It's a little cheaper in Makro than Halfords (£9.49+ VAT for 5L + 1L fee). I think it's around £15 in Halfords for the same.

Mobil do a 20W-50 "Drive Clean Oil" apparantly!

http://www.mobil.com/USA-English/Lubes/ ... n_Oils.asp

Seems 20W-50 is used in aviation. Not sure about stuffing it in your porsche but available here: http://shop.pilotwarehouse.co.uk/subpro ... o=19110023

Posted: Mon Oct 04, 2004 9:22 pm
by Robster
thanks chaps...

Robster

Posted: Sat Oct 01, 2005 8:35 am
by hot66
Thought I'd keep adding my 'oil experiences' to this thread :)

I have been running Silkolene Pro R 15w-50 in the 2.4S all summer. I personally prefered the Mobil 1 that was in the car last year. The Mobil 1 seemed to keep cooler when I drove trhe engine really hard. I also have both rockers leaking more with the silkolene but I don't think this is an oil problem. New silicone rocker gaskets to be fitted for next year :)

Posted: Sat Oct 01, 2005 3:53 pm
by IanMcLeod
I am interested in your experience with Silkolene vs Mobil because I am using Silkolene Pro 15w-50 in my car as well and have been very pleased with it with no leaks or any other problems.

Was the Mobil 1 you used a 15w-50 or was it thinner?

Ian.

Posted: Sat Oct 01, 2005 8:06 pm
by hot66
can't remember what grade of Mobil1 I was using, pretty sure it was similar weight. I'll have to dig out the receipt.

TBH there is nothing between the 2 oils. I notice I get temp into the silkolene quicker from a cold start ( which is good) , but I also notice after very hard driving on the country roads the temp seems to lift a bit higher than it did with the Mobil1 ( although in both cases the temp never increased by any large amount). This might be because I am now more confident with the car & thrashing it more ;) :lol:

Either way, I am very happy with full synthetic oil :)

Posted: Fri Oct 07, 2005 9:55 pm
by hot66
I have just bought some Valvoline Turbo V 15 / 50 for the '67.

£ 7.80 for 5 Litres :shock: which I think is a a bargain :)