Recent content by ylk1

Maybe rebuilt engine?

Just curious, have you done any DCT gear oil changes?

Thanks for pointing out Delo 600 ADF! Never seen such low ash oil with completely different chemistry. Wish there was some info on the anti-wear agents used.

I've seen a lot of discussion on ZDDP in this forum but very little on it's ashless counterparts. Lot of alternate options in literature. But can't commercial products info. Anyone knows what's the dominant ashless anti-wear agents out there? Tribochemistry and Morphology of P-Based Antiwear...

All the ones above - Advanced clean : dated 28 May 2025

My bad: Haven't seen the first page. Correct SDS: 5w-30: 5w-20: 0w-20:

Very interesting. Grp-1,2 & PAO. I think I've never seen such composition.! Grp-1/2 for sludge solubility?

I think most people would attribute zinc/phophorus content to ZDDP levels in engine oil. ATFs/Gear oil formulations would be different and would emphasize EP additives (sulphur) more than ZDDP along with/without friction modifiers imo.

Just stumbled on this updated 2025 literature survey in Tribology Letters Journal: https://link.springer.com/article/10.1007/s11249-025-01968-3 Interesting tidbits (not chat-gpt generated) : ZDDP has anti-wear(from P via phosphate films), extreme-pressure(from S via FeS2, ZnS formation) and...

Was able to find chemical limits of dexosR (2021 version) finally. Details in this thread: https://bobistheoilguy.com/forums/threads/gm-dexosr-dexosd-specifications.381726/ SAPS/Phosphorous/Sulphur and even Evaporative loss limits all are pretty loose compared to ACEA or other OEM specs. Looks...

Can't argue with that. Agree that there should've been more choices. should've tested other lines of oils for DexosR earlier.

just curious, did you have any info? or any insights from german forums?

I agree. If only they'd disclose something. Maybe they are discovering things as they go along requiring different formulations. Remember seeing a lot of 991.1 engines having valve train issues. Most of them seemed to be fixed by 991.2. They even added additional oiling supply for crank...

Nice car! Back then, ~2014-2016, pricing for GT cars used to be reasonable. ~20k more than Carrera S. Porsche became too greedy now. 250-300k for a GT is crazy. You can get a radical and have enough money for 2-3 seasons of professional racing.

Yeah. I'm just thinking out loud here. Only someone with definitive data could confirm it. As most wear happens at cylinder liner-piston ring before cam-bucket, maybe balance of formulation is needed. Surprising to see Porsche and Chevrolet recommendations going in opposite ways. More info on...