Have you ever wondered about oil reports?

[Mike6158]

When I bought my TLC in June of this year (2014) it had 150,000 miles on it.

On 7/7 I changed the oil, front and rear diff, and transfer case oil, took samples, and sent them to Blackstone Labs so I would know what my baseline was

I'll post the comments section since it's hard to format the analysis section

Mileage at the time of sampling: 152,071

Engine Oil

MICHAEL: Copper is a bit high in this first sample from your LC's engine, but at just 8 ppm, it's really hard to call this level a problem. Everything else looks good next to the universal averages (which are based on ~6,700 miles of oil use for the 2UZ-FE engine), so we'd say you picked up a really nice one here. Since all the other metals are fine, and copper is just twice the average level (that's the threshold for highlighting a metal), we've decided to leave it unmarked this time, so we can issue a perfect report. The TBN was strong 4.8. Start with 6,000 miles next oil. Nice!

Front Differential

MIKE: The front differential sample had some high silicon, and iron is well above average (although not quite high enough to mark as a problem level). As you can see from the universal averages (based on ~31,400 miles of oil use), iron is typically the dominant metal, and since iron tracks with time on the oil, this level wouldn't be so bad if this differential fluid has seen 60,000 miles or more. Just like with the transfer case, silicon could be residual sealers, especially if this is the factory fill of fluid. It could also be dirt. Hopefully it will drop next time, either way. The TAN was okay at 3.8.

Transfer Case

MIKE: The transfer case sample has some pretty high levels of wear metals, but if it's possible that this fluid has never been changed in the life of the vehicle, this may not be so bad. Universal averages are based on ~32,000 miles of oil use, and not only will metals tend to read higher after more use, but metals may also be elevated if this is the factory fill of fluid, which would still have residual break-in material in it. The TAN was 4.1, not too acidic, so the oil is in good shape, physically. Now that it's been changed, check back in ~20,000 miles to monitor.

Rear Differential

MIKE: The rear differential has much lower levels of wear metals, and lower silicon as well. Maybe the rear differential fluid was changed more recently than the front diff? If so, the rear diff would have had more of a chance to wash out the silicon and metal that we saw from the front diff sample. Or, it's also possible that the silicon in the front diff is from an abrasive contaminant (such as dirt), and that's causing excess iron wear. The TAN was lower here, at 2.1. This sample looks pretty good, but check back on both diff fluids in 20,000 miles and we'll see how trends develop.

Fast forward to 9/2 and it's time to change oil in the engine

Mileage at the time of sampling: 160,143
Elapsed miles: 7,272 (oops)

Engine Oil

MICHAEL: You might be surprised by the results in this report. You were probably expecting to find high metals because you went much longer on the oil than you normally do, but really, the changes since the last report are minimal. That shows you've got a healthy engine under the hood and that it didn't mind leaving the oil in use for a longer interval. The viscosity was fine for a 5W/30 grade oil and no harmful contamination from dirt, fuel, coolant, or moisture was found. The TBN was robust at 5.5, so you could easily go 9,000 miles next time. Your engine can do it!

Not bad piece of mind. I'll do the diffs and transfer case at 20,000. I'll be interested to see what they look like. I have a feeling that, even though there were records that they were all done, the front diff wasn't done (because of the drain plug appearance). The transfer case doesn't show that it had ever been done.

 

[apdxyk]

What oil and filter, please? Did you have a chance to redo your diff and transfer case fluids?

 

[Mike6158]

I have not checked my diff and transfer fluids yet. I am past 20k on the change so it's time. My last oil sample had right at 10k on it and it came back fine.

I use Mobile 1 5W-30 oil and a Toyota oil filter
I used Amsoil Severe Gear 75W-110 in the diffs. I may switch to Mobil 1 simply because I don't have to buy it online.

 

[crimsonaudio]

Sent a sample from my last oil change off in December - they want me to run 10k on the next oil change:

 

[Mike6158]

Nice!

 

[2001LC]

I've noticed over the past 12 years. The T-case get dark about 20K, front diff ~25k and rear diff >~35k miles. This follows your report.

I use M1 for all lubes (easy to find & KISS) and M1 synthetic oil filter.

I start to notice a little "D" vibration if I go much over 5k miles on oil change.

 

[apdxyk]

Thank you all for sharing. JFYI, M1 5W-30 HM has the highest HTHS = 3.3
Regular M1 5W-30 has 3.1 and the EP version 3.0
RedLine 0W-30 is at 3.2
(going from memory, and ll those formulations can change)

I have no idea which number is scientifically sound. I know that Germans prefer 3.3 and above, and it doesn't translate in demonstrable longevity gains as we all know.
There is a strong bias to higher numbers in my head, since the same Mobil and Shell sites for Australia and Emirates recommend weights all the way up to 20W-50