can anyone tell me what oil to use for my 1975 kombi its an 1800cc manual. I was told to use 50-20 but I wanted to get a second opinion from you guys. ill be travelling up to darwin so it will be pretty hot if that makes any difference.

You'll soon discover that "What oil should I use?" is one of those questions that everyone has an opinion on, particularly if they get started on the mineral versus synthetic argument.

I suggest you search for previous threads and draw your own conclusions.

Nearly all modern, good quality mineral oils are suitable. 20W-50 is about right. Pick a name brand you like and stick to it. I've always used Castrol myself - just the normal 20W-50 Castrol multigrade. I haven't tried GTX2 or 3 or whatever.

Don't bother with synthetic oil. Whether it works better than normal mineral oil is not the point - with VWs you change the oil every 5000km, and it's too expensive for that.

Buy an extra 4 litres and keep the container in your Kombi. Check the dipstick every time you fill up with fuel, and top up the sump if necessary.

I agree with mnsKombi I would NOT recommend any oil to anybody, I use Penrite HPR5 (5 - 40) , it is only about $10 a litre! &
Mobil super XHP in the Humber ( only have to change it once a year- 8 litres an oil change!!) 20-50 oil is just standard "oil"

I used to wonder about this myself, the old strait verses multi grade argument has been around ever since multi has been available.
I used BP Visco changed every 5000 up until 150.000, then I switched to BP Corse plus, the old girl has clocked up 260.000 now and is still going well, fingers crossed it will last a bit longer yet!

Rob.........

I like the advice from Phil but would add , dont overfill, it takes time for the oil to run down in the motor once switched off.
So if you get all conscy and fill oil till the full line straight after paying for the fuel then later when the oil all runs down it will be over full.

You probably wanna check out the API site
http://api-ec.api.org/about/index.cfm?bitmask=001002003002000000

In particular this page. It is a pretty idiot proof guide to the confusing API markings.
http://api-ep.api.org/filelibrary/ACF2AD.pdf

Basically VW engine's only really need an SC quality oil. But the latest is SL. Some crap oils available are as old as SG which is obsolete, just goes to show how crap they are.

Valvoline has an oil called XLD plus (used to be premium). It is around $14 for 5 liters, and is of a very high quality SL/CF. I use it for my car and bike.

Any SL oil should be a very good oil which should easily handle the demands of a VW motor.

oils aint oils sol. just use the right one, the one with the lowest viscosity you can afford. the engine cools by way of the oil going through your oil cooler. the thinner the oil the mor oil goes through the cooler the more heat is dissipitated off and the engine runs at its right temp. its not rocket science but pretty close to it. ask any good Kraut mechanic.

The viscosity of the oil will not effect how much oil goes through the oil cooler. The oil pump is a positive displacement pump.

If it is pumping 100cc/min of oil, it is pumping 100cc of oil a minute. They is no effect by viscosity.

If you are going somewhere warm, use 20W50. If you are going somewhere colder use 10W40.

The most important thing is to check the level and maintain it every day your on a long trip.

This must be done with the car on flat level ground or as close to as possible.

And the engine must have been off for at least 5 minutes to allow the oil to drain back to sump.

Probally the best time to check would be first thing in the morning when the engine is cold.. no doubt your not going to sleep on a hill so the car will be level.

DO NOT OVER FILL THE OIL LEVEL. this can and will create more problems than you need.

I've written SOOOO much stuff on oil for the VW engine, I just had to put my 2 cents in here.

I'm adding a chart below, but unfortunately I can't get it to line up right - (anyone wont to tell me how to switch text in this forum?) so you'll need to do a cut/paste into your word processor and switch the font to courier (or any other fixed space font).

[pre]
Viscosity cST @ 40 degrees C
70 130 160 200 240 300 350 480 1340
______________________________________________________________________________________
| |
| SAE Gear Viscosity Number |
| ________________________________________________________________________________ |
| |75W |80W |85W| 90 | 140 | 250 | |
| |____|_____|___|______________|________________________|________________________| |
| |
| SAE Crank Case Viscosity Number |
| ____________________________ |
| |10| 20 | 30 | 40 | 50 | |
| |__|_____|____|_____|______| |
______________________________________________________________________________________
2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58
viscosity cSt @ 100 degrees C[/pre]

You'll note that the "cold" temp Cst is 40c and the "hot" temp is 100c in this chart.

So at even colder temps the oil will obviously be more viscose, but this chart will at least give you the idea of how vicosities work

Just for info, viscosity is measured in Centistokes (Cst), and the higher the number, the more viscose the oil is (the longer it will take to run through a hole of known diameter).

Now look at the 30 weight engine oil (VW used to recommend 30 weight for above freezing temps).

The "cold" Cst is about 200, and the "hot" Cst is about 11-12.

So we know the engine can cope with 200+ Cst oil and get it through the oil cooler OK (yes yes I know the engine has an oil bypass relief valve or two but that's to protect the pump if needed - the 200Cst oil WILL flow through the oil cooler).

Now look at a 20w50. That means it behaves as a 20 when cold and a 50 when hot. The 20 has a cold Cst of about 160, so we know the engine can take that OK (since it can also cope with 200Cst in a cold 30 weight oil).

But when hot, the oil is now 18-20 Cst - a little thicker than the straight 30 but still WELL under the 200 Cst we know the engine can cope with.

The result is a thinner oil when cold for easier starts, yet the oil stays a little thicker when hot, so it becomes a better "gap filler" in tired engines and helps prevent the oil pressure dropping. It also means a little less oil consumption.

There is absolutely no reason why you can not use a modern 20w50 engine oil in the VW - VW started recommending exactly that in about 1975 when multigrades had become reliable (they first appeared in about 70).

The 20 rating is good for temps down to minus 15c (the VW Owner's Manuals all have an oil viscosity chart in them), so unless you live in Thredbo or My Bulla you probably don't need to bother with a 10w30 or 10w40.

And just for info, if you have an engine which is getting tired and burns a little oil, you can quite safely use a 20w60 or 25w60 such as Castrol XLA or Penrite HPR30.

So if you like to use a straight 30 like VW used to recommend up to the mid 70s, go right ahead - the engine will be fine with that - but don't forget to change is to a 20 in winter if you live in a snowy area of Aus). And if you prefer to take advantage of the multigrades, go right ahead and do that - VW started recommending them in the mid 70s.

One thing though - to get an oil to become a multigrade, the oil compnanies add substances called long-chain polymers. These are curled up when cold (so they don't bind with each other and the oil stays thinner), but when hot, they stretch out, overlapping and "strengthening" the bonds through the oil, so they prevent it thinning as much as otherwise.

But the polymners don't lubricate - so you only want as much as it takes to do the job and no more.

A 10w30 and a 20w50 contain about the same percentage of polymers, but a 10w40 has much more polymers to meet the wider viscosity range. That means less "oil" in that oil, so I tend to avoid it, especially since the Aussie climate will (in 99% or Aus) be just fine with a 20 "cold" number oil anyway.

And you don't need to bother with synthetics, they are expensive and offer NO advantages for the VW engine. You can't extend the oil change periods, since the open-sump design of the VW engine (and lack of oil filter on most) means you have to change the oil every 3000 miles (5K km) anyway.

Synthetics will certainly work just fine, and don't be put off by the stories of "wont carry heat to the oil cooler" which just isn't true (synthetics are resistance to DECOMPOSITION by heat, but they are still just hydrocrabons and will absorb/carry heat much the same as any other oil), so you can use Synthetics if it makes you feel good, but the engine doesn't need it.

The VW engine is not particular about the brand of oil - VW went to great pains to say "any decent brand will do" in the Owner's Manuals, but it's probably better to avoid the el-cheapo supermarket brands - they MIGHT be OK but some might have cheaper additives which may not cope so well with the slightly higher engine temps of the aircooled VW.

Synthetics in the GEARBOX are a different matter though. The normal mineral oil is 80w90 or 85w90 Hypoid mineral gear oil, which works well, but the synthetic 75w90 gear oils available now make for easier cold-car gear changes (the cold 75 number) and the 90 hot number still protects the box when hot. Since it stays in the gearbox for 30,000 miles it gets a decent "long life" workout, so the higher price is not so much of a burden. Don't worry about the old "GL5" argument either ...the first GL5 oils were slightly corrosive when hot on the bronze components in the VW gearbox, but the oil companies soon fixed that and brought out a new GL5-MT1 standard, so just look for the MT1 anywhere on the pack or the Data sheet on the oil compnies web site and you can be sure it will work OK. The older GL4 standard is just fine too.

And just for info, take a look at that chart above again... notice that a 90weight gear oil is about the same viscosity as a 40-50 engine oil? The actual numbers don't mean anything in particular - but engine oils use the numbers up to 60 and gearbox oils use numbers from 70 upwards, just to separate the two types of oil, since you can't put gear oil in a sump or visa versa.

I'll get off my soap box now :-)



[Edited on 11-4-2003 by aussiebug]

blah blah blah blah
anyway i bought myself a 5 litre thing of good oil, used that up then whenever i got my car tuned i get the emtpy 5 litre filled up with the oil that my Mech. uses which is 20w-50 good german brand(cant remember) $1 a litre he charges me, or there abouts i think.
:bounce

Migbt be blah blah to you Skewy, but the number of times this thread comes up - the guys out there DO want to know...

Regards

So what your saying Rob is...

Rob your a bloody genius. unbelievable wealth of information. thanks, fish

Ive seen an oil thats 25-70
would that be fine in a 1600tp?

cheers
Josh.

Mmmmm... So a synthetic GL5 oil is OK for the Gear box Rob?
I've been debating what to get for my Gear box of late, I was keen to try a synthetic but was not sure about the GL5 rating.
Is there any problem putting a synthetic oil in (the gear box) at oil change time? There is mineral oil in currently.
Thanks,
Andy

I had a decent chat with Leon from Leon's motors (Brisbane VW shop) about GL5 oils.

Now Leon has built more VW gearboxes than probably everyone here put together, and he said he has never seen any evidence of the additives in GL5 oils effecting the bronze in the VW gearboxes.

He said plenty of people are scared to use it because of the rumours the EP additives in it eat bronzes / brasses, but he said the VW gearbox doesn't appear to be effected.

In his trike he uses synthetic gearbox oil with a special additive because of it's low friction, he notices an increase in HP on the dyno.

I just use Penrites transaxle oil in my gearboxes, and it seems to be fine. I tend to break stuff before wearing it out anyway :o

oh, and I have also been hearing rumours from the US that using synthetic engine oil has lead to some apparent premature oil seal failures in VW engines. Something in them makes the seals swell.

[Edited on 12-4-2003 by Baja Wes]

[Edited on 12-4-2003 by Baja Wes]

Hi Wes,