If I remember correctly, it seems others that did the delete on their diesel pickups saw huge improvement in the aluminum wear. I wouldn't be surprised if your next sample will show lower aluminum, too, because it'll have the benefit of having been deleted from the beginning. Yours has come down but I bet it drops some more next time.
I've never asked anyone before, but does the engine feel more lively and get better fuel economy now? It sure seems like the engine would breathe much easier without the filter and maybe the exhaust routing is smoother, too ?
I used to have a 2005 Cat C15 in a Freightliner Classic XL and each muffler was actually a catalytic converter type thing ( I'm tired and drawing a blank on the technical name). Removing those and replacing them with free flowing mufflers from Pittsburgh Power really made an enormous difference in the way the engine could pull on the hills.
Good to know that a delete may lower aluminum wear - thanks for the advice on that!
I'm no expert, but think how the engine feels post-delete is largely based on what tune is used. I did a full delete, both dpf and egr. Tune I'm using is a tow tune, which only increases HP by a small amount - I was advised to do this because of towing 14K quite a bit and was told that regular street or high performance tune may cause things to start melting/blow. For my particular engine, the delete and tune has resulted in the following:
(1) mpg increase of about 1 mpg. Its more or less depending on driving conditions (e.g., larger increase in the 50-60 mph range, and lower increase at 70-80 mph, from what I can tell). Also, my understanding is that the only way to really know mpg increase is by hand calculation, because the display tool on the vehicle is often inaccurate.
(2) oil temp about 4 degrees lower on average.
(3) engine is a little more lively taking off, and a little more lively during mid-speed operations, but can't tell much difference at highway speeds. With my typical 14K load in tow, it is significantly easier getting out of the hole now.
(4) fuel dilution gone from the oil, presumably because no more fuel being injected on the exhaust stroke during regens (this may be particular to 6.7L engine due to regen design).
(5) shifting is smoother/better.
(6) sound is almost the same, but can hear the turbo a little bit more. No smoke from exhaust. My dpf shell is still on - just doesn't have anything inside of it now - so no new exhaust piping for me.
Can't think of anything else right now.