Engine oil Castrol or ZIC

I use Castrol Edge 5W30 LL04 (M). I doubt what you read about sludge is true. Regular oil and filter changes are way more important than which brand you use.

i use castrol 5w-40 european vehicle. fully built and no issues at almost 30k

I use the Castrol Edge oil. I was doing 7500 mile oil changes and on this last one bumped that up to 10k miles. I sent out the oil for analysis to decide if I want to step up to an even larger interval. The comments left by the tester: 'Your CX5's engine looks good in analysis! Your results look really good by comparison after the 10,000 miles. Metals are all within good wear ranges, with iron even showing below-average steel wear. Nice! Titanium is just an additive in Castrol. Very nice! Go 12k miles next fill.' I will heed their advice and go 12,000 miles on this next one.

Castrol German 0w/5w-40

Doesn’t sheer down…

I used Castrol edge cos that's what my audi used from the factory.

For my 1.6 diesel I use Castrol Magnatec 0W30 Stop-Start C2 which was recommended to me by cox motor parts (great store for Honda parts)

It doesn't really matter as long as you get one that meets the specifications for your car which should be VW502 in your case. Mobil 1 0w40 and Castrol 5w40 both support that and are widely available for a reasonable price.

I’ve been using Castrol’s 5w-30 with the RN0720 spec (for DPF filtered diesels like yours and mine), it’s the best oil for thins engine. 100.000km doing oil changes every 10k and it’s as good as new, very good fuel economy and no leaks

Castrol Power 1 isn't a bad oil, but I'd say not the best either. I have only used LiquiMoly as an alternative, so far and I rate is better than the Castrol but it did cost almost 2x as much too.

Car has been at the stealership for three weeks. Same transmission TC seal leak. Bolts and seals also needed replacing. Car is 45 days old with 4K KM’s.