Testing the limits of oil and filter performance

[Ian-was-here]

After 150k mi of smooth sailing on my trusty Sienna I've decided to test the waters and push the envelope with a 7,5k mi oil change interval. Using Castrol GTX High Mileage oil and a Bosch premium filter will send the oil to Polaris Laboratories for a closer look. Let's all wait to see how this experiment unfolds.

 

[c04st4l_crisp]

After 150k mi of smooth sailing on my trusty Sienna I've decided to test the waters and push the envelope with a 7,5k mi oil change interval. Using Castrol GTX High Mileage oil and a Bosch premium filter will send the oil to Polaris Laboratories for a closer look. Let's all wait to see how this experiment unfolds.

Castrol GTX High Mileage oil and Bosch premium filters are dependable choices but keep an eye out for any unusual engine behavior during the extended interval. Excited to see what the lab results reveal. Keep us posted!

 

[Ian-was-here]

Sent the oil sample to Polaris Lab and am now waiting for the results. Can't wait to share what the analysis reveals about the extended interval experiment!

 

[JinnoVado]

Good plan.. Just keep an eye on the oil analysis results to catch any issues a bit early. Long as the oil stays clean and the engine runs smoothly, extending intervals can save time and money. How often have you done oil analysis before?

 

[Ian-was-here]

Time to report back with the numbers, as the lab results have been in for a bit. The analysis showed viscosity was strong and all the wear metals looked great for this engine. The final verdict is that the oil was nearing the end of its useful life, so while it worked, I believe 7,500 miles is the absolute upper limit for this oil and filter combination.

@JinnoVado I've done 1 analysis before this. My goal was to establish a benchmark with my previous change interval before pushing the envelope.

 

[misterKnowItAll]

Time to report back with the numbers, as the lab results have been in for a bit. The analysis showed viscosity was strong and all the wear metals looked great for this engine. The final verdict is that the oil was nearing the end of its useful life, so while it worked, I believe 7,500 miles is the absolute upper limit for this oil and filter combination.

@JinnoVado I've done 1 analysis before this. My goal was to establish a benchmark with my previous change interval before pushing the envelope.

What markers indicated that it was nearning it's life? How's the oxidation and tbn?

 

[SiennaScout]

Great job on the test! I did something pretty similar with my old Accord when it hit around 140,000 miles, I pushed the oil change interval to 8,000 miles using a high mileage synthetic oil and a Wix XP filter. I also sent a sample to Blackstone for analysis, and they found that the TBN had dropped to about 2.1 with oxidation starting to rise, but the wear metals were still well within spec. It definitely confirmed for me that 7,500 to 8,000 miles is the max for that setup. It's awesome to see others experimenting with this too, those reports reveal a lot more than you can figure out from just checking the dipstick.

 

[cargokinghybrid761]

That's a fantastic initiative! My neighbor ran a similar extended interval test on his old '08 Tundra, but he went with a premium PAO synthetic. He noticed that the viscosity began to thin out more than he anticipated around the 8,000-mile mark, even though the wear metals looked good. It's amazing what those reports can uncover beyond just TBN and oxidation levels. Keep us updated, I'm really interested to see your results from Polaris Labs