Longtime lurker, first time poster. Thought you folks might be interested in some of the oil testing I’ve been doing with my 2019 Mustang GT. I’ve done a series of long drain interval, ~10k miles, tests using various 5W-20 oils but that info is going to take some time to put together so I figured I’d start off with what I’m currently into. Seeing how well oils and my engine hold up to HPDE track use. Diff and trans oil too but I haven’t sent that stuff out for analysis yet.
The Setup
Car: 2019 Mustang GT PP2
Oil: 10 quarts Castrol Edge 5W-50, API SP
Use: 30 min sessions, 4 hours total time on track time, 1 hour was wet where the oil wasn’t significantly heated, ~250 total miles.
Ambient temp: High 40s low 50s F
Baseline Oil Temp: 200-205 F
Peak Oil Temp: 260-265 F during the dry sessions, ~220 F during the wet
My Mustang didn’t come with a real oil temp gauge, so these values are from a sensor I installed in an oil filter sandwich plate. All samples were sucked out through the dipstick tube.
Oil info from Castrol
KV @ 100C: 16.7
HTHS @ 150C: 4 (not on the product sheet but that’s the value they told me when I asked, which is a far better response than “sorry we can’t say” from Mobil 1 and Pennzoil)
VI: 177
Problems
It was freezing outside while I was prepping my car and the old oil filter wasn’t budging. I wasn't in the mood to dig out my oil filter wrench so I left it on meaning the new Castrol was contaminated with around 1/2-1 quart of Motul 8100 EcoLite 5W-20 with ~3000 miles of use.
Results
Right off the bat the oil is out of grade but I’m sure the Motul contamination is significantly contributing to that. The kv100 viscosity and oxidation values pre and post track are unchanged so this stuff really wasn't bothered by having some heat put into it.
The lab flagged the titanium value 18 ppm but that’s just part of Castrol Edge formulation. When I ran Edge 5W-20 my titanium values were up at 17 ppm.
Iron wear is about what I’d see from 2000 miles of daily driving with 5w-20. 3 ppm of lead raises an eyebrow since I’ve never seen lead show up before, even from the UOA on my factory break in oil when wear metals were through the roof. I also didn’t fill up with gas at the track which I’ve heard can sometimes cause a little lead contamination. Possibly a sign of bearing wear, possibly just a fluke from some contamination during sampling. We’ll have to see if that’s a consistent thing that shows up from track use.
What really surprised me was how much ZDDP was in this oil. I don’t think Castrol advertises it anywhere but this stuff really has some zinc in for an API SP oil, 1169 ppm phosphorus 1386 ppm zinc. Thats close to what Valvoline advertises in their high zinc VR1 racing oil.
~770 ppm phosphorus and ~870 ppm zinc were my average values when previously running Castrol Edge 5W-20, which is also right in line with values I saw when using Mobil 1, Valvoline, and Motorcraft.
Conclusions
Again I’m amazed Castrol doesn't advertise the ZDDP in this oil, I’m not complaining but you’d think it would be a selling point. I’m also impressed the viscosity and oxidation didn’t budge. I’ll definitely run this stuff again down the road once the weather gets warmer and with the old oil fully drained out.
The Setup
Car: 2019 Mustang GT PP2
Oil: 10 quarts Castrol Edge 5W-50, API SP
Use: 30 min sessions, 4 hours total time on track time, 1 hour was wet where the oil wasn’t significantly heated, ~250 total miles.
Ambient temp: High 40s low 50s F
Baseline Oil Temp: 200-205 F
Peak Oil Temp: 260-265 F during the dry sessions, ~220 F during the wet
My Mustang didn’t come with a real oil temp gauge, so these values are from a sensor I installed in an oil filter sandwich plate. All samples were sucked out through the dipstick tube.
Oil info from Castrol
KV @ 100C: 16.7
HTHS @ 150C: 4 (not on the product sheet but that’s the value they told me when I asked, which is a far better response than “sorry we can’t say” from Mobil 1 and Pennzoil)
VI: 177
Problems
It was freezing outside while I was prepping my car and the old oil filter wasn’t budging. I wasn't in the mood to dig out my oil filter wrench so I left it on meaning the new Castrol was contaminated with around 1/2-1 quart of Motul 8100 EcoLite 5W-20 with ~3000 miles of use.
Results
Right off the bat the oil is out of grade but I’m sure the Motul contamination is significantly contributing to that. The kv100 viscosity and oxidation values pre and post track are unchanged so this stuff really wasn't bothered by having some heat put into it.
The lab flagged the titanium value 18 ppm but that’s just part of Castrol Edge formulation. When I ran Edge 5W-20 my titanium values were up at 17 ppm.
Iron wear is about what I’d see from 2000 miles of daily driving with 5w-20. 3 ppm of lead raises an eyebrow since I’ve never seen lead show up before, even from the UOA on my factory break in oil when wear metals were through the roof. I also didn’t fill up with gas at the track which I’ve heard can sometimes cause a little lead contamination. Possibly a sign of bearing wear, possibly just a fluke from some contamination during sampling. We’ll have to see if that’s a consistent thing that shows up from track use.
What really surprised me was how much ZDDP was in this oil. I don’t think Castrol advertises it anywhere but this stuff really has some zinc in for an API SP oil, 1169 ppm phosphorus 1386 ppm zinc. Thats close to what Valvoline advertises in their high zinc VR1 racing oil.
~770 ppm phosphorus and ~870 ppm zinc were my average values when previously running Castrol Edge 5W-20, which is also right in line with values I saw when using Mobil 1, Valvoline, and Motorcraft.
Conclusions
Again I’m amazed Castrol doesn't advertise the ZDDP in this oil, I’m not complaining but you’d think it would be a selling point. I’m also impressed the viscosity and oxidation didn’t budge. I’ll definitely run this stuff again down the road once the weather gets warmer and with the old oil fully drained out.
