Engine Oil....

[steve.h]

Hi guys, I have a question for you all, I have been given some oil by a friend for the car, it is Morris VS plus 15w-40. It is ment for diesel engines but my friend says he has always used it in his petrol engines with no problems. I have just looked this oil up on the morris website and it is listed for HGV ! ! !

My question is would you guys put this oil in an Alfa Romeo 2.0 TS petrol engine, looking on the Alfa forums they all go on about the engines being very fussy about the oil it has.

 

[the repair man]

Nope!

 

[brightspark]

motor oil

go down halfords or to a decent motor factors and they will tell u the grade u need. i got a few telling me 20 40 oils were fine and they wernt it takes 10 -30 fully synthetic even garages dont know what to use

 

[zzr1200]

I'm a commercial vehicle mechanic by trade, I haven't purchased engine oil for any of my petrol cars for the last 35 years, perks of the job....

 

[steve.h]

Hi ZZR, you are in a similar situation to my friend, he also never buys oil for his petrol car... The oil he has given me is in the "fleet" section of morris website and it is 15w-40 I see it says about being a long drain oilbut I dont quite know what that means, my handbook says 10w-40 for my car so would this cause a probelm, my problem like most is money if I have to go and buy oil it would likely be cheaper oil anyway so would I be better off with the oil I have been given or cheaper petrol engine oil. I guess I could add a litre of the "petrol" oil and the rest the diesle oil, that would save a few quid.

 

[armalites]

The modern trend for many cars these days petrol and diesel seems to be 5W30.

Most oils these days are Multifleet and can be used in either.

Years a go I bought a Fiesta XR2 that had always had tractor oil in it and that engine was very clean inside and I sold it with 155K miles on it and it still felt fresh, no rattles.

Many handbooks wiil specify an oil but normally there will be a chart for different ambient conditions.

I used to run my 2 previous Volvo T5 on 15W40 multifleet, no issues, one was 300K+ and the other 200K+

I would try it, some car forums are hiding places for all the scaremongers in the world and you'd never buy a car again if you believed everything on some of them.( I know this is a forum also but it's clear people take the common sense/thought through approach)

If there is a continued supply then just change it more often, I do mine every 3-4K, a bit OTT but I've never broken an engine since I started doing it that way.

 

[AndyStobbs]

You should also factor in wear when specifying oil. Whats right for a tight engine isn't neccessarily best for an engine with 100k+ Miles on it.

As mentioned earlier, ambient temps play a massive part in selection.

 

[chevy2]

An ongoing reduction of zinc thats added to modern engine oils to meet a combination of regulations, emissions and envoironmental targets has became quite a big problem in older engines that the older style flat tappet cams opposed to the newer roller style,
Google zddp and cam failure for the full story.
This problems often rears it ugly head during the crucial first 15-30 minutes of 'breaking in' the cam,
The zinc in the older oils used to cling to the cam lobes and protect them as were often only oiled by crank splash.
So users of the older style engines should steer clear of especially the newer lightweight synthetic oils and stick with the old school mineral type 20-50 oils.
A zinc additive is available from some of the bigger cam manufacturers,
infact to keep it on topic in the usa a common trick to break in cams in petrol engines is to use diesel oil as it has a higher zinc content.

I've personally suffered from this oil problem and caused around £500+ of internal damage to an all new small block chevy.

 

[normspanners]

as a mechanic I don't think you would have any problems using the 15w 40 as against the 10w 40
if you can get enough, just change it more often, as oil thickens with age in an engine.
and this can cause far more problems than a slightly diff grade.
All this s**t about long service intervals 15-20k causes more problems than anything with sludge build up etc I have stripped engines that have had the manufactures stipulated services and they have been vert solid inside, 6-7k max for me

 

[MrFluffy]

Diesel oil vs petrol oil is down to two basic things, the diesel oil has more detergent, and as a side effect it cant cope as well with low temperature sludge formation. So my take on it is if you know your engine is clean inside and not prone to sludge, it wont kill it provided you haven't got a engine that promotes sludging by design, but if you have something of questionable parentage that the extra detergent power could work loose back into general circulation or something prone to low temperature mayo (hello rover v8 on short journeys and all those long since dead 2l pinto's) then stick to S oils. I have a big drum of tractor oil at the back of the barn, but I've never even been remotely tempted to use it in anything else. Price of oil looks expensive till you have to rebuild something...

 

[DrNik]

its more the time between services than the oil in my opinion, i always service things bang on time and sooner if ive been giving it some stick

 

[AndyStobbs]

as a mechanic I don't think you would have any problems using the 15w 40 as against the 10w 40
if you can get enough, just change it more often, as oil thickens with age in an engine.
and this can cause far more problems than a slightly diff grade.
All this s**t about long service intervals 15-20k causes more problems than anything with sludge build up etc I have stripped engines that have had the manufactures stipulated services and they have been vert solid inside, 6-7k max for me

I was under the impression oil viscosity (at operating temps) is reduced with age, due to the break down of the VI's through shear forces.
That only deals with the original oil structure though, and I can see that absorbtion of ash/soot would tend to thicken the oil overall.

Its a massively complex subject on which I wish I knew more...

 

[zzr1200]

Totally agree with Chevy and Norm, fleet oil in the car, semi syn in a motorbike and that's only because fleet oils can cause the clutch to slip, I won't use fully syn oil.

 

[hotrodder]

5/30 this, 10/50 that is just viscosity. The API/ACEA specs are the bits i pay attention to, even manufacturer specs if it's going in something relatively modern. Valvoline do an oil with lots of ZDDP for those that have lots of money in an 'old' engine that's hard on cam gear

 

[normspanners]

A good few year ago I used an oil supplier that in every tank full gave you 5 free oil post mortems/ laboratory tests and a small diesel with 10w 40 in 5k short runs etc turned into a straight 90w !!!
due to sludge /carbon build up
vehicles doing higher speed motorway mileage faired better with less thickening.
I stripped my sons newly bought S/H corsa down he had just bought ( I know what i'm buying HUM!!!) and could not believe it, the cam cover came off and left a 'sand castle' impression of the cover over the cams !!in the sludge.

 

[zardoz]

Alfa's are fussy, or maybe thats just the owners being snobby ? (No offence meant here whatsoever) Its just that when i worked in a garage, we used to have two or three Alfa owners used to bring their cars in and all three of them used to bring in the own little gallon cans of Alfa brand oil and Alfa spark plugs and filters etc.

Apparently, I found out years later that it said in the handbook to only use Alfa brand products, so they did.The boss was a tad annoyed as like all mean garage owners he used to make a mark up on the cheap oil he sold and pretended was Castrol. So he stiffed them on the service bill.

But who knows whats best for an engine except the people who make them ? I'd give the oil away or keep it for a future vehicle.

 

[Sean]

new clean oil (most brands & fuel types) is better than dirty old oil .

 

[normspanners]

Poclain diggers etc said you had to use their oils especially the hyd oil coloured blue, which when we tested it was a LOT worse in wear properties than our stock oil and about equal to our jack oil! but the poclain oil was about twice the price!
I have used oil from sponsors, fully syn VERY expensive stuff £60 gall and I'm going back a long time here when syn's were being introduced and if the cars suffered an overheat problem or somesuch you would then have low oil pressure problems and have to change the oil to get the pressure back up, where as the older mineral based oils would stand an overheat better and maintain the pressure.
I have stripped thousands of engines in my life and believe me fresh oil every 5-6k is allways better,no matter what type, rather than leave the oil in till the so called service intervals, because the oil spec you put in, after a few thousand miles, has totally changed, especially if a car has had an overheat, throw the oil.
Dont forget car manufactures want you to spend money on parts !!! engines /gearboxes etc so yeah keep your oil in for 20,000 (rubbing their hands)
Fleet oil is NOT cheap oil it is for what it says, various vehicles in a fleet, made, FOR THEM TO LAST!

 

[hareng]

Quite right motor factors often spec the wrong grade.
Past cat spec was 10w/30w i put in 0w/30w as the oil vidcosity flows better when cold and still has the 30w for normal temp.
Did try 0w/40 in last car, it was sluggish.

Current motor using same spec 5w/30 i use 0w/30w. Nearing an oil change and running low nipper had some 15w/40w i topped up about 1 litre. This now transponds to 10% less economy and performance but has quitened the 20 noisy tappets.

 

[flash of light]

oil is cheaper than metal, i used to use 15w40 in a datsun 120y because it was cheap, just cost me more in fuel .