Engine oil IDEMITSU or FUCHS

Been running Fuchs 5W40 lately, N52 with 130k kms

I use Fuchs Titan SuperSyn 5W-40 - widely considered to be the lowest-consumption oil for the M54 engine, and it's very cheap.

Mann filter.

I use idemitsu rotary 20w50

I stick to Idemitsu. I have a Sohn adapter fitted, so it's 10-30 Idemitsu in the engine, twice a year and Idemitsu Premix in the Sohn adapter and in the fuel tank.

Fuchs Titan 5w30

I don’t use the Mazda-branded version, but Idemitsu is my go-to oil in all of our Mazdas

Idemitsu is the only premix and engine oil I’ll use ... you can order it for a good price from TREx performance out of NJ and he will ship

The oil was Idemitsu Synthetic 0W-20 with 12.5k miles on it. Once again, trace metals and flashpoint were within normal range. I also ordered a TBN to measure the amount of additive left and that showed there was still plenty of active additive remaining.

In terms of oiling, get a sohn adapter so your apex seals aren't being lubricated with crankcase oil, and instead are injected with rotary-specific oil, like idemitsu.

I've posted my UOAs on TDIClub and BITOG. The factory fill was additive depleted at 5400 miles. The Fuchs 507.00 in the next fill was good for 7-7500 miles. It might have gone longer, but I changed it out in advance of a long trip. Bottom line is that preliminary evidence is that the 507 oils are inadequate for extended OCIs in the 3.0L motor.