Engine flush worth it?

I think if you've been good about changing your oil at the right intervals, don't bother.

what engine do you have? 1.8T or V6?

I've heard rumors of 1.8Ts, particularly in Passats and A4s, having oil sludge problems. If you've been good about changing your oil you're probably OK but if you've been a procrastinator, you might have some sludge building up. However, the question is really if an engine flush would make things better or worse. It could loosen up stuff only to make it get caught in yet another place in the engine.

So if you're good about changing your oil at the specified intervals, don't bother at all. Otherwise, not really sure if you'd benefit anyway...it's still a crapshoot.

You know, the other thing that occurred to me is that an old trick that people have suggested (and I've tried) is if your oil is a quart low, dump in a quart of ATF. Run with that for a little while (not forever, but maybe

1000-2000 miles, then get your oil and filter changed. ATF supposedly is higher detergent than oil and will help clean things out a little bit. I've done this on my '91 GTI a few times and it did eventually seem to make the valve lifters a little less sticky/noisy.

It is really a wallet flush, your wallet.

With today's oils and engines engine flushes are seldom of any value and are likely to do as much damage as good. Save your money. BTW don't use one of those engine flush fluids (commercial or home brew) engines are only suppose to run with oil in them not solvents. If you really are worried, change your oil and filter, run it 500- 1,000 miles and change it again.

On a related note, does Redex a significant difference. For £10 (from Costco) I thought I'd try some. It consists of a) 2 big bottles to use ever 10k-20k (can't remember the exact figure) - a whole bottle in 50l of fuel b) A smaller bottle to use - 100ml per 50l of fuel

When I first got my 1.9 TDi I was getting about 600-620 miles per 50l of fuel. This went down to about 520-540 since just before it's last service After the last service it went up to 580 Now on redex I'm back to 620 - that's with 1 big bottle, plus about 3 refuels

Having said that, it may be partially down to a) no longer having to endure major roadworks on a large stretch of motorway b) watching my speed Although the difference of about 100 miles sounds quite difference, it's actually just a range of 47-56mpg which I guess is quite acceptable?

If its a 1.8T DON'T do it. These engines are prone to sludging - particularly in the USA. For some reason we don't seem to see much of it in Europe - not sure why. If you use a standard type flush on this engine (and a number of others) what can happen is that big lumps of crap get dislodged very quickly which can then block oilways, filters & worse still the oil pump pickup screen in the sump with obvious consequences..

If you want to run any kind of de-sludger/flush then the best stuff around is probably Auto-RX

This has been quite widely used on

1.8Ts with great success - it involves a 2 stage process over about 3000 miles & works slowly but seemingly very effectively without the risk of blockages etc. Hop on over to & read the forums for accounts of people using it. Also read "Bob is the oil guy" at The problem with the 1.8Ts is that they have a relatively small oil capacity & so the oil has to work quite hard. More so again because its a Turbo. You can help your engine a lot by making sure you let it run at idle for a minute or so before you switch it off to let the turbo cool down a bit - particularly if you have been driving quite hard just prior to parking up. If you don't do this there is a risk that the oil that's left in the turbo at switch-off literally cooks down into a nasty black gunk.

In the US VW has now put out a TSB mandating the use of Synthetic oil and a much bigger oil filter (in fact the one that goes on the deisel engines!). Ask your dealer about it & if they don't know about it then find another dealer!

HTH

I.

Here in the USA the engines were only speced for dino oil unlike from what I heard for the euro engines which used synthetic. Along with owners who don't change their oil.

Dealers here don't use fully synth on them. VW dealers use Castrol oils here & tend to use Magnatec which is a semi synth. Also I believe VWoA works on

5K Oil changes.....here its 1 year or 10K miles or now, under the long-life servicing, upto 18K miles or 2 years. For that I think they do use Synthetic (castrol Syntec I think).

rgds

Iain

For what it's worth, I run 15W-40 diesel oil (dino) in my '83 rocco (173 k miles), because of the higher detergent content. I considered an engine flush, but decided against it since there was the risk of loosening gunk around seals and ending up with oil leaks. I can't say how much it's helped, but I have no leaks significant enough to reach the driveway. You can also get Quaker State for older engines, which has additives that I believe help old seals to swell up and reduce leaks. HTH, H2Only

Thanks very much to all of you for your feedback and advice. It turns out the dealer didn't offer the engine flush this time. I don't know if they discontinued it but the flyer is no longer visible on the service counter.

On the other hand, they added a US$5.25 oil treatment on top of the oil change (the service description said they used 5W-30, btw). I wonder what could that be?

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