Best way to reduce blowby? 15W-40 or synthetic? Or motor honey?

Or, fixing the engine problem causing blowby.

that's a brilliant idea! why don't you come on over and fix it for me in a jiffy on my gravel driveway in the 90 degree heat with the black flies, my 2 kids climbing all over you and my wife b******* at you for not playing with 2 kids or paying attention to her. Or you could take it to your shop and wave your magic wand.

I have an even better idea why don't I just go and buy a brand spanking new 2012 mb diesel from the stealership.

If you are running a diesel, and you are on a diesel forum so I'll assume that is the case, you should already be using a 40 weight oil. The number that matters once the engine is warm is the last number. If your blow by is excessive with 40 weight oil, the next step is a 50 weight oil. It can be hard to find diesel ratings on say a 20W50, but there are some out there. Mobil 1 has a 15W50 with a diesel rating. The Motor Honey approach will work, but you have no idea what your oil viscosity is after adding a bottle, so I would try the higher viscosity formulations first.

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'97 E 300 D

I've had the car about 3 months and haven't driven it much. . I have a couple gallons of Valvoline 15 w 40 diesel formulation.

I'm going to reply to my own post and call myself a dumbass .
I will first change the oil with 15 w 40 can take it from there .

Is this a hypothetical question? Is there a particular car you have in mind? What are the symptoms that lead you to believe there is a blowby problem? Is the crankcase ventilation system working properly?

Sixto
87 300D

85 300d. High miles. Smoke wisps from fill cap anid vent tube to filter. car has great power though.

this sounds like normal operation on a well maintained car to me.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

This is what I was thinking.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

X3!!
It doesnt sound like you have a blow by problem.
If you must add snake oil to fix a problem you dont have, go ahead. The US economy needs all the help it can get !

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Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

Oils wisps from oil fill and vent tube when it gets warmed up. And high miles

You mean oil smoke, right? If it's wisping, that's normal, check that I should say that is GOOD if the car has more than 200k miles. Having some smoke is normal as the motor ages.

Blowby isn't wisps... it's smoke under pressure shooting out when you pull the oil cap, accompanied by a light shower of oil droplets in the vicinity of the fill opening if it's serious.

As long as the car performs okay, blowby is a Feature not a Problem

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Mac
2002 e320 4matic estate│1985 300d│1980 300td
Previous: 1979 & 1982 & 1983 300sd │ 1982 240d

“Let's take a drive into the middle of nowhere with a packet of Marlboro lights and talk about our lives.” ― Joseph Heller, Catch-22

They kinda all do that. How much does the oil filler cap rattle if you set it lightly over the oil filler hole?

Sixto
87 300D