1.8T oil (eliminate sludging) crasher or a8 tech.

[rhencullen1989]

Hi, been reading some of your posts regarding the 1.8T tendancy to sludge and block the oil pick up. Basically my 1996 1.8T A4 is booked in at a reputable indy next week, what oil should they be putting in it? its done 170K and i have owned it since 120K, i change oil every 5k with semi synthetic vw silver synta oil, its also backed up with full vag history before i bought it (not sure what oil was used by them). Is it wise to change to fully synthetic after such a high mileage on semi, you mention a bigger oil filter, would this be used anyway? also do you recommend an engine flush prior to draining out the old oil? i am reluctant to remove the sump because i shall be changing it early next year. my driving style is more granny than hamilton!! any info would be greatly appreciated. Ta.

[Crasher]

I would use VAG Longlife III oil and the two year long life standard size oil filter (06A 115 561 B) but change them both at six month or 6K mile intervals. I don’t bother with the larger capacity filter; I don’t see the need for it. A huge contributory factor to sludge formation is immediately shutting the engine down after a hot high speed run. You should sit at idle for a few minuets (such as in a motorway service station) to allow the turbo to “spool and cool”, i.e. slow down and cool down. This reduces the chances of the oil in the turbo boiling up and carburising as this is the reason for most of the sludge debris which descends into the sump directly from the turbo return drain.

[rhencullen1989]

Ok, thanks crasher, i assume that the VAG longlife oil is a fully synthetic oil? what is your opinion on engine flushes, i used to use the wynns engine flush in my 10 valve quattro when the tappets got noisy and it did seem to do some good but i am not sure on the turbo a4, could it create a problem by disturbing a build up of sludge that is happily sitting undisturbed in the corner of the sump!!!!!

[Crasher]

Yes, the Longlife III is fully synthetic. My thoughts entirely on engine flushing, I have seen it block many a gauze strainer over the years.