The 2.5% fuel seen on the short 3,511 mile interval change and a bit on the previous change is pretty much entirely due to not letting regens finish. This was a period when I was scrambling around getting ready for a 3 week, 4,000+ mile trip and simply didn't have time to drive around the block to let the regens complete. The <0.5% changes prior were the same fuel, same overall useage and same Ford PM-22a additive. The last change on the report covers the 4,000 mile trip hauling a 2,000# truck camper and towing a 10,000# trailer, the 3,511 change was immediately prior to that trip. The 4,000 mile trip halfway across the country and back surely included some bio-blend, but shows no fuel dilution, so (quality truckstop) bio in itself seems to not be an issue fuel dilution wise.

 

Have you always run the mobil 1 5w-40? Reason I ask is I was on BITOG and read a UOA from a guy with the same oil and his iron was abit elevated as well, I also notice that on my UOA's it is slightly elevated too.......think we may be on to something here......

 

M1 5W-40TD since the very first oil change on the new truck. Note that the last change with higher iron included 4,000 mi with 12k of combined load, previous reports without such loading were lower iron.

To borrow from another post I made:

I've done enough personal testing with synthetic oil to convince me that it is indeed notably better than conventional. I've had a large diesel engine (pre-emissions) with recently changed conventional oil running while I added a mere 1/2 qt of synthetic to something like a 28qt sump and I could literally hear the engine smooth out as that oil went into circulation. <!-- / message -->

 

I hear ya I run Synthetic in everything, I like you am a firm believer!!

I just sent out my latest UOA to blackstone yesterday, we shall see how it comes back. I just remember seeing a lot of UOA's that used rotella T6 and they all looked great, mind you the UOA on BITOG that I was refering to I just read the other day...thats why it so fresh on my mind. Dont get me wrong I think the M1 TD oil is great oil and I have been using it for years (in my 6.0 as well) .

 

Another reason to let regens finish is the cost of getting the exhaust up to temperature before the DPF is hot enough to start burning the soot.

From the logs I've been taking from several full regens, it takes around 5 minutes of normal driving (more if sitting in stop and go traffic) before the DPF temperature (EGR13) gets up to 1000-1100F which is when soot starts to burn. Looking at the temperatures between EGR12 and EGR13, the next 5 minutes is when the bulk of the soot starts burning on its own, and then it seems to taper off over the remaining 10-15min (or longer if in slow traffic).

Shutting down regens during the first 5 min of regen before the DPF has reached combustion temperature is essentially a complete waste of fuel, some of which invariably ends up in the oil

Stop-and-go traffic and regens don't mix. Keep regens from starting in stop-and-go traffic if you have a length of freeway ahead of you. Shut it down by throwing it in neutral/park until you can get moving, then let it burn once you're on open road.

 

I started a new thread with my latest UOA from Blackstone, looked great!