Well I was recently using valvoline 15/40 only tapping on cold start for a few seconds or after a long drive sometimes.
It had been 1000ks since my head gasket replacement/vrs kit install so I thought id go with a new oil and filter.
Changed filter from a ryco to a valvoline (not the best but we only had valvoline or bosch at work and the bosch return holes are tiny, valvoline ones are same as ryco so I went with it.
Used penrite pro15 wich is a 15/50 grade. Best we had at work.
Now engine has higher oil pressure at idle and gets pressure quicker but when the engine warms up it is noiser then with the 15/40.
Either way higher oilpressure + smoother opperation = win for me.
EB 3.9l 207,000ks.

I've used GTX 20W/50, produced LOUD knock on col startup for a few seconds (till the oil got up)

Then went to Magnatec 10W/40, the knocking wasn't as loud, but was still noticeable untill the oil got up.

Now using Nulon 15W/40, there is maybe 3-4 small knocks at startup.

It seems to me, too thick an too thin have similar results, knockin on startup.

15W/40 is on the spit to bring noise to the minimum.

As a note, a mate with a 6cyl BA MK2 did similar experimenting as I did and found that te oil in between was the best for minimum knock..

Double post

i run 15/40 on both my cars with no problems, both smooth and hardly ever tap on startup.
one of them has 330,000+km's. changing oil/filter every 5,000kms.

i wouldn't worry to much if it only does it now and then, and only for a few seconds.

Last edited by Troy on Sun May 08, 2011 12:50 pm, edited 1 time in total.

So you think it's all about experimenting to see what suits the car best? maybe ill try 20w40 then and see how it goes when cold.

I lasts for a good minute before it becomes really quiet and can not really hear it, then when I start driving the really quiet tapping is gone within another minute. so it's a bit more then a few seconds, there's no major problem with at least trying a 20w40 oil is there?

nah, but you could also check the tappets.

since i dont know what tappets are is there a guide on how i can check them myself or am i better off giving it to a mechanic to look at?

Mosqeeto: its 20w50 not 20w40. and screw using "whatever filter i could get"

Tickford_6: because in the real world. engines wear

I was hoping you would back your self with some sort of diagnostical process, or with some actual useful information.
But as always cheap meaningless one liner is all you could muster.

So tell me, How do you know his engine is worn to that point. He hasn't taken any 'real world' oil pressure readings. The only thing he's really told you is that his HLAs are have slight leak down.

He also hasn't said it's burning oil.

The reality is there are only two reasons to ever use thicker oil,
The first is low oil pressure.
The second is burning oil to the point of fouling spark plugs.

If it doesn't have either of those, then thicker just isn't needed.

Further, if his problem it ticking at cold start he needs an oil that is thinner when cold as it's easier for the oil pump move and will fill HLAs faster.
The noise goes away after a while and doesn't come back when hot so the 40 (hot) is perfectly fine. If anything he should try a 5w40.

I thought there was a 20w40 and a 20w50 ? also, that post makes sense, thanks tickford, should i try a 10w40? does a 10w40 even exist?

You can get right down to 0w40,
Fuchs do a 10w40 it's called GTO 1040 I believe they have just changed the name of it, but most shops will still have the GTO labled bottles for a few months.

You may not be able to fix the problem with oil. It wouldn't hurt to drop into the local ford dealer and pick a motorcraft oil filter too, part number for your engine is AFL1

Have look through some of the oil company websites, look through the product range and try to find a semi syn 5w40 or 10w40.

ok will do, can you explain why i should look for a semi synthetic?

Last edited by Mosqeeto on Sun May 08, 2011 4:06 pm, edited 2 times in total.

Fuchs, Valvoline, Mobile, Motul. They are in any particular order.

You won't find any lower then 15w40 in a mineral oil, unless it full of viscosity index improvers (VIIs), Which you don't wont, as they break down (shear) and form sludge and the oil goes out of grade.
A 10w40 mineral oil with a lot of VIIs would probably 'shear' down to a 10w30 over time.

Semi syn starts with a better base oil and is more stable without the need for VIIs, less VII is better, NO VII is best. (which is why Penrite is not in my good list)

Some oils like some of the castrol range are marketed as synthetic but are not true synthetic oils.
They are molecularly cracked mineral oils. Which is not a bad thing, they are very good oil. Just not to be confused with a true synthetic.

Fuchs market that type of oil as semi syn and the bottle is labled with 'MC' or 'MC' will be part of the name.


In short You will need to use a semi syn to find a good oil in the 5w40 10w40 range.
You'd need to go a true full syn oil to find a 0w40.
But recommending a full syn oil in a well used engine will probably start further argument.

http://www.valvoline.com.au/files/productpdfs/66.pdf
http://www.valvoline.com.au/files/productpdfs/6.pdf
http://www.penriteoil.com.au/products/m ... /hpr/hpr_5
http://www.penriteoil.com.au/products/m ... hpr/hpr_10
http://www.castrol.com/castrol/productd ... Id=6008869

Those were the ones I could find, The only one that says semi synthetic appears to be the HPR 5 and 10 from penrite, however they don't have a 10w40, also I could be completely missing important information about the others.

Should I try the HPR 5?