UOA Question- Should I start to worry?

[MCompact]

Car: 2007 Mazdaspeed 3 77500 miles
Oil: Mobil 1 5w30

Backround: I have had a used oil analysis performed at every OCI beginning at 9800 miles The Fe number at that mileage was 40 ppm(5000 mile OCI). From that point on the Fe number decreased to 25-28 ppm while the OCI remained @5000 miles- dropping to 19 ppm at my prior oil change(5200 mile OCI). The 5w30 has always remained in grade and the TBN has never dropped below 3.0. No fuel dilution above a trace and no issues with insolubles, silicon, water, or coolant. The initial Cu number was 83 ppm(!) but quickly dropped into the 1-3 ppm range. Pb has always ranged from 0-2 ppm.

Question: My last OCI was 7400 miles. Vehicle mileage was 76700 miles. If anything, I have been driving the car easier than I usually do. The used oil analysis revealed that everything was normal except for Fe, which jumped from 19 ppm to 38 ppm. I realize the OCI increase may be responsible for part of the increase, but not all, especially considering that Cu remained at 2 ppm and Pb at 1 ppm. So, is the Fe spike a legitimate cause for concern? Thanks!

 

[demarpaint]

Short answer is no. Read what Doug Hillary has to say about iron in UOA reports. I'm pretty sure that will ease your mind.

 

[ottotheclown]

May I, without further explanation, say switch to Pennzoil Platinum 5w30 and see what happens. Others have and found a difference.

 

[MCompact]

Originally Posted By: demarpaint
Short answer is no. Read what Doug Hillary has to say about iron in UOA reports. I'm pretty sure that will ease your mind.


Thanks. I've read most of Mr. Hillary's posts and I realize that a Fe number of 38 ppm isn't all that large. What worried me was the sudden spike, which is something I haven't seen happen before.

 

[d00df00d]

Here's Doug's post in one thread about Fe readings:

https://bobistheoilguy.com/forums/posts/2065496/

Look at the method used to obtain the wear numbers on your UOA. Is it ICP?

 

[demarpaint]

I wouldn't call your higher iron number a spike. Unless I read something wrong you also increased your OCI, there's no free lunch, LOL. Increase the OCI increase the wear metals. I'm no expert but IMO you're fine!

 

[addyguy]

I wouldn't really worry about it - just a blip on the overall picture. with other metals in line it's nothing to worry about, really.

Fe tracks with mileage, and you increased your OCI by about 45%. Yes, your Fe doubled, but if you allow for a 45% increase for the mileage increase, it didn't actually go up that much at all.

Hope that last part made sense....

 

[TallPaul]

I once had an OCI with over 400 ppm iron after driving all summer in dusty conditions (construction zone) with the PCV hose hanging loose and sucking air. Over next few OCI it dropped to double digits. This was probably a good 30-40 thousand miles ago and the engine is still running strong and not using any oil. All the gory details are posted here, just not time to search for it. Probably around 2005-2007 I am guessing.

 

[MCompact]

Thanks for all the helpful responses. I've been going back and forth on whether to keep the car and I don't want to make a decision based on incorrect assumptions. I think that I'm going to try another 7500 mile OCI and see what happens.

 

[NateDN10]

If it continues to trend up in future used oil analysis, it bears looking into. For now, it's just noise.

 

[Spockian1]

Hmmm... Mobil 1 5w30, 7400 mile OCI, 38 ppm Fe.

As we in the BITOG crowd white-knuckle it with extreme OCI's of 7400+ miles (my 1988 owner's manual specifies 7500 miles) using super-premium oil... the rest of the world (at least the ones who don't blindly do Jiffy-Lube every 3000 miles as a religion) takes their cars in once every few years (They only drive a couple of miles a day, to work and back, after all.) to let smiling techs drain stuff out of their oil pans that the old guy in the original "Blob" would never have considered touching with a ten foot pole.

38 ppm Fe at 7400 miles? You should be delighted. That's well into the noise. Nothing.

And to the guy using this opportunity to promote PP... oh, please. PP is an excellent product, as is M1. But this situation does not require an emergency PP intervention. Though if you are a Pennzoil fan, you might want to do at least one round of PU to clean out all that gunk that PP left in your engine that PU can get out. It's not "Factory Clean(tm)" unless you've run PU in it.

And a Hip! Hip! Hooray! for marketing gimmicks!

 

[Eddie]

That is parts per million and is a non issue i.e no problem. PPM results can easly very 2-3X from run to run.

 

[CloudX]

Hahaha marketing gimmicks....

You should switch to something better than M1 in the Disi. Pennzoil Platinum / Pennzoil Ultra work good. Your oci is too long. You should keep it below 5k. Mazda was off that day. Like when Hyundai recommended 5w20 in the gen coupe's 2.0t and then comes out with Tsb saying 5w30