Well there you go, you had the answer all along. Rotella 15w-40 is very solid oil, just keep using that. Don't fix it if it ain't broke.

Just like there's more than one way to skin a cat, there are lots of completely acceptable oils for these engines. I only went with Delo 15w-40 in mine because it's also a very solid oil and was the least expensive. When I switched to synthetic 5w-40 for the cold start help(6F, it sure helped) I went with Mobil 1 because again, solid oil at the best price.

I've seen two stroke guys try a BUNCH of different oils. Looking for the absolute two-stroke perfection oil, they bypass all the ones that worked just fine and eventually try something that DOESN'T work. That gets expensive. Sometimes the best bet is to stick with what's proven to work just fine, even if it might not be 100% the best available.

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617 swapped Toyota Pickup, 22-24 MPG, 50k miles on swap

Synthetic doesn`t cause things to leak. But as I have read others posting, that if the engine is older IE gaskets/Seals that are well aged, the Synthetic can clean out the gunk (what ever) that was keeping the Gasket/Seal sealed up.

If there are oil leaks/drips that develop, maybe this is a good thing to discover, as...well maybe these parts were on there last leg anyway?

Iam not so sure about the Oil Gauge suddenly leaking with the change, as you said, coincidental. Anytime the Oil gauge starts to leak, isn`t a good thing to find out at anytime, what ever type of oil is used.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

At least until they change formulation on you :/

Sixto
87 300D

That must be it. It couldn't possibly have anything to do with fact that synthetic oil is "smaller" at the molecular level or that 0W or 5W oil behaves differently than 15W oil.

I have a tough time believing that a metal-sealed banjo bolt would develop a sudden leak due to "gunk removal." I am totally convinced that synthetic oil is more enthusiastic about leaking than conventional oil.

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When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

I can assure you the leak is coincidence.
The internal bourdon tube tube failed.
FAQ: How Does a Mechanical Gauge Work?
............
https://www.google.com/search?q=internal+bourdon+tube&client=firefox-a&hs=ukn&rls=org.mozilla:en-USfficial&tbm=isch&tbo=u&source=univ&sa=X&ei=wP_BUoDRG-jSsATEtoD4Dg&ved=0CCwQsAQ&biw=1280&bih=859

Been there many times, there is NO possible connection.

.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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