Engine oil Castrol or PENNZOIL

I use pennzoil euro spec, I only go through about a quart between 5k oil changes.

I did notice the German Castrol had a smoothing effect on the big 5-cyl.

For my 24v I use: Castrol Edge Professional OE 5w40

Best oil IMO is Castrol 10w40 high mileage part synthetic, usually good specials at local auto parts stores and Walmart.

I'm in LA and I use castrol oe professional 5w-40 on my rebuilt 16v. The best oil I've used so far in my mk2 and I've tried a lot (Rotella t6 5w-40 Mobil 1 15w-50 and Total Elf 5w-40) all synthetics. Try it out. You won't be disappointed.

I use 5w-40 Castrol Syntech oil in my 2010 3.6 CC. I believe that if you are going to keep the car for a long time( over 100k miles) then I would use the thicker oil for better lubrication and wear protection. Owners in warmer areas like myself should use the 5w-40 due to the higher summer temperatures which will break-down the 5w-30 oil faster than the 5w-40 oil especially after a 10k oil change period.

I've been running Castrol 5w40 in my car and have had no problems.

Castrol GTX 5W-30 with an STP filter. NY area. 178k miles with no HLA tick so far. Had some 10W-30 in it before during the winter and the car didn't like it too much, took over 3-5 tries cranking to get it started.

I've been alternating between the OE Castrol (with the free maintenance) and Pennzoil Ultra Euro 5W-40 (502 compliant and recognized/certified by Audi/VW) in 5,000 mile intervals. I've had both tested, and the TBN is higher on the Pennzoil and the viscosity always perfect (Castrol tends to read thinner than 5w-40 on the samples I've sent in for analysis).

In my gen 3, I've used Castrol OE Professional 5w40 (the Castrol in the gold bottle that the dealer sells - oil has a green tint to it), both when I did the 5k mile change and when the dealer did the 10k change.