Fuel Dilution strategies

[JMcTaggart]

Last year I put a bypass filter on my '09 stock 2500, Smarty Jr. Hoping to get increased oil change intervals. I had it analyzed at 10,000 miles, everything was great, negligible fuel dilution. But 6,000 miles of that were towing my camper across the country and back. Sampled same oil 6,000 miles later, 5.2% oil dilution, did an oil change right away. But this time I know that I had several short trips to home depot, etc. and not much towing and not as much hiway miles.
So I did some research on oil dilution, and am looking for driving strategies to minimize this in my Bluetec engine. Two things I have started is a) not short trips. I go out of my way to get 15 or 20 mile in (is that enough?). b) I read that babying it (which I would do to improve fuel mileage) was a contributor, so now I use a fairly heavy foot to get up to speed, after some warm-up. c) I drive until a regen is finished, if at all possible.
Anyone got any other thoughts on this?

 

[JMcTaggart]

167,000 miles on the truck.

 

[cerberusiam]

First thing, it isn't a Bluetec engine, that is a Mercedes thing for after treatment. A comparable system is the SCR system on the 2013 newer trucks. Since you don't have an SCR truck it is the plain old dirty EGR system that was notorious for contaminating the oil with fuel.

Two solutions, hook a trailer to it and drive it hard and all the time, or, delete it. With an unloaded truck you cannot get enough engine load to get sustained EGT's hot enough to do any good with oil contamination. Even running at hiway speeds mostly constant they will still contaminate the oil before an oil change should be needed. Just the way that early EGR system worked, less than adequate.

 

[JMcTaggart]

Thanks. Yes, I should have said Bluetec after treatment (There's a Bluetec logo on the tail gate.)
Not the answer I was hoping to hear. I'll have to keep up with the oil analysis to make sure of when I need an oil change.
I guess I should mention that I have the EGR unplugged and blocked off, I run around with the CEL on all the time. Maybe that helps some, we'll see.

 

[cerberusiam]

IIRC the regen is done with extra fuel late in the injection cycle so same problem exists with excess fuel being used and contaminating the oil.

Dealers stick all manner of decals on trucks not having any idea what they are doing. You should not have an SCR truck so it is not BlueTec, if you have a DEF tank you have to keep filled that would be very unusual.

 

[EDankievitch]

The EGR is not causing the fuel dilution directly the regen cycle to clean out the DPF is. The EGR just adds to the soot load that must be burned off. If your EGR is blocked off then it’s just the normal soot form the way the engine was tuned to keep cylinder temps down and prevent NOx formation. They say up to 5% is normal .

 

[Ozymandias]

I'm the only one that think it's weird to delete hardware and let the software alone with a permanent CEL on?

 

[cerberusiam]

Poor mans delete, unplug and block the EGR. The 3rd gen emissions systems are not very intelligent so can get away with some stuff.

 

[Jihn]

I'm the only one that think it's weird to delete hardware and let the software alone with a permanent CEL on?

I thought that the cel is normal, when I bought my truck it was on, asked the seller to take it to a dealer and bring me the report, he did, the report said I was missing the dpf, egr and the cat, and all codes pointed to that, I was told that the truck would run normally or better without those items. It did do some weird things, until I put a Smarty program in it, no problems since, and it gets checked every other year for pollution and passes easily.

Jihn

 

[cerberusiam]

No, it won't pass emissions with all those parts gone. Where are you testing and what exactly do they test for? CEL is an auto fail with emissions testing.

What smarty programmer did you use, S-67?

 

[Jihn]

Not where I live, they do the stomp and look for smoke test, I pass with flying colors, my truck doesn't smoke much, and the parts that are missing show up on the government test sheet. They know they are not there, but it was imported from Texas that way, and they approved it for import. So yes it does pass even with CEL, I can even apply for an extra year between tests because my passes at 1/10 % of what I'm allowed.

Jihn

 

[Jihn]

What smarty programmer did you use, S-67?

Yes

Jihn

 

[JMcTaggart]

My question is- what is it about towing that reduces or eliminates the fuel dilution in these models? I've tracked the regens, it still does it while towing at about the same rate. Is the oil temp increased? Sometimes the coolant temp is not increased, when towing on level ground.

 

[Ozymandias]

You really should run a proper tune, then the regens and all associated with it is gone, including the CEL.

 

[Killer223]

just change the oil sooner, oils are cheep, really, these engines are so easy on oil, get what ever is on sale and of the proper grade for the climate you live, and de3signed for a diesel, and enjoy.

 

[JMcTaggart]

You really should run a proper tune, then the regens and all associated with it is gone, including the CEL.

When you say proper tune, you mean with everything deleted? Otherwise there will be regen. I'm running Smarty Jr, I have noticed that with increased timing, the regens are shorter. I have no plans to delete any more than blocking the EGR. I still have to go back to stock once a year to pass emissions testing.

 

[cerberusiam]

Not where I live, they do the stomp and look for smoke test, I pass with flying colors, my truck doesn't smoke much, and the parts that are missing show up on the government test sheet. They know they are not there, but it was imported from Texas that way, and they approved it for import. So yes it does pass even with CEL, I can even apply for an extra year between tests because my passes at 1/10 % of what I'm allowed.

Jihn

Where would that be that they ignore missing parts? I get the stomp test but the way the EPA has been cracking down on parts and CEL's that is unusual. These trucks are Federal emissions, it would not matter where it came from if the parts are missing in most places that is a fail.

 

[Jihn]

if the parts are missing in most places that is a fail.

I had that argument with the seller, he produced the passing test sheet, if it was a car it would fail automatically, I'm in Ontario, Canada, they switched the commercial vehicles to the opacity tests, and stopped testing cars, and yes I was amazed that they pass my each and every time, anywhere else it would be a fail. They test according to year and 2008 did not require all those parts, but yes I agree with you it should be a fail every where.

Jihn

 

[cerberusiam]

Ahh, north of the border is different so now it makes sense.

 

[xcc_rider]

Minimizing incomplete regen cycles will definitely help reduce fuel dilution as will minimizing short trips.

I can't comment on towing vs regen duration and frequency as I just can't remember that far back.