Mixing oil? For topping up (1.8 20vt Golf) - both 10w/40 semi but....

Stormster

Stormster

Stormster

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Based on whats in my car at the mo (Quantum Synta 10w/40 semi synth, been ran on it for 4 years solid since previous owner bought it)... can I just top it up with this stuff? I am planning an oil change next month come payday and car will have done about 7500 miles on the current oil.

The oil I am wondering if I can just top up with is oil I had for my old Corsa. 10w/40 semi synth, GM oem stuff.

Got the same ratings/codes on but obviously doesn't say VW 500, 505 etc approved... both bottles do however say ACEA A3, B3, API SL/CF and the VW one doesn't have anything extra apart from VW 505 approved.

Here's the front of the bottles with the codes:

oils1040.jpg


Prob only needs 1/3rd of a litre, just till I do an oil change next month... if not I'll have to buy 2 x 5L of what it's been ran on for ages as you can't buy top up bottles and it takes 4.5L in an oil change. Was just hoping I can avoid having to buy any for a month if this stuff will do for a top up for maybe 7-800 miles till I get it booked in for a change.

Thanks guys :)
 
You need to be careful that you use the right oil in a 1.8T or you'll get problems.

The right oil is VW Approved fully synthetic. Oil for your Corsa wont cut it.
 
See this is another ongoing thing aswell... I've been looking into it for a good while, what oil should be ran in it etc.

There doesn't seem to be a solid, concrete, uniform answer.

A lot of people run 5w/30 Quantum Platinum stuff from the dealers, fully synth.. and on the other hand a lot of people are running 10w/40 semi synth such as the stuff I've got at the mo, Castrol Magnatec etc.

My car has been fed the Synta Silver stuff for the last 4 years now, is on 132k and doesn't tap or anything and runs pretty well, no issues, doesn't use loads of oil etc... so I'm not sure what to do. The previous owner led me to believe it was fully synth, but it's not. However it's been fine and I'd say 50% of people I've asked on golfgti.co.uk and uk-mkivs.net run 10w/40 semi synths in their similar age Golfs with the same engine as mine.

A lot of folks have suggested not swapping to anything thinner than 10w/40 also due to my milage incase it burns past the turbo oil seals (I think lol, I'm no mechanic).

I think I'll give the GM oil a miss... but I've been trying to decide what oil to buy for a few weeks now but no one can recommend one thing.

Even the stealers said "Yeah mate, you can run the Synta Silver semi synth or the Platinum fully synth, your choice". My mechanic checked on his Autodata and it says 10w/40, aslong as VW approved 500 (same in car manuals) but doesn't say semi or fully synth so..

Ongoing thing! :)
 
Its worth spending the extra and running it on Fully Synth 5w30, 10w40 can lead to a world of clogged up pain, its simply not worth the risk.
 
i cant remember which spec the 20vt was designed with (either vw502 or vw505) but when the car was produced the recommended oil was 10w40 semi.

due to the heat involved due to the turbo (and the stupid length of time people keep the oil in) there are loads of 20vts out there with tons of burn oil in them

you can top it up with the greek stuff to tide you over but you DO want to put a semi decent 5w40 fully synth in there
 
You really need to make sure that the oil meets the VW specification required for your car.
Explanation of VW specifications can be found here:

http://www.opieoils.co.uk/c-742-vw-engine-oil.aspx

My Octy vRS uses 5W-30, but it must be with VW Specification 504 (as my car is on variable services, so needs long-life oil).

The "correct" 5W-30 oil for my car is around £40.
The "incorrect" 5W-30 oil is a lot cheaper.
Stick to what the manufacturer recommends.
 
[TW]Fox;15820689 said:
You need to be careful that you use the right oil in a 1.8T or you'll get problems.

The right oil is VW Approved fully synthetic. Oil for your Corsa wont cut it.
Click to expand...

Isn't the VW Approved fully synthetic only needed for the extended service intervals? On normal ones I'm sure you can use 10w-40 semi synth. I'd personally use the GM stuff to top up as it's a very small ammount and it'll be changed within a month anyway.
 
Gribs said:
Isn't the VW Approved fully synthetic only needed for the extended service intervals? On normal ones I'm sure you can use 10w-40 semi synth. I'd personally use the GM stuff to top up as it's a very small ammount and it'll be changed within a month anyway.
Click to expand...

5W30 was originally used for the extended service program, and 10w40 for the 10k service intervals, however its now best practice to use 5W30 for all service schedules and remove the 1.8T units from the extended service programs, the 10W40 oil is not of high enough grade for the 1.8T and can lead to lots of sludging problems.
 
The only thing I'm concerned about with the 5w/30 fully synth is if it's thin enough to cause issues burning past the turbo oil seals?

The Quantum Synta Silver in there at the mo is VW 500 and 505 approved and numerous places inc. the dealer say it's fine in my engine. The manual does too, albeit ten years old as someone else pointed out :)

Yet strangely if you quote a different engine code in a newer model Golf, Leon etc they say no to 10w/40 VW approved semi synth oil. Odd as it seems...

As it stands, over the last 4 years it's been running the Quantum Silver stuff, it's been changed every 5k. As a consequence, the last owner fubared the sump nut and just before I had it, it had a new sump (VW genuine part) fitted. It's very shiny :D

It's done about 6k on it so far, I don't want to be changing every 5k like he did, so was aiming for every 7.5k on average.

Will have a look on Opie Oils now, last night very quickly it was giving weird engine codes which didn't mean a lot to me for the 1.8t Golf.
 
On Opie Oils, if I say it's a "VW Golf GTi 1.8i 20V Turbo 1997-99" as they classify it, it's bringing 10w/40 semi synth good quality oils up. If I click on however, the "upgrade engine oils" drop down list, it's listing 5w/40 fully synth stuff.

If I say it's a "VW Golf 1.8T GTi 20V Turbo (QG0/2 - 110/132kW) 1999-04", or the other 3 similar options, it lists the same as above.

So... where next? lol :) I've submitted on the recommend me an oil form, to see what they reckon considering it's remaped, town driving generally speaking and aiming to change it every 7.5k.

But it seems, as initially stated, there's no right or wrong to an extent.
 
5k intervals on the 10w40 semi ought to be fine

but on a remapped car (which i imagine youd drive hard?) i can only imagine youd put 5w40 in there

quantum platinum. i got 20L of the stuff today :P
 
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