93 Merc 400E, Castrol Edge 10W-40. 5k severe miles

[vivaUkraine]

Hello fellas. Interesting UOI results that I'd like to share:

Car: 1993 Mercedes 400E (32 valve V8, 275HP (when new)
Mileage on the car: 105k miles
Mileage on oil 5,025 miles/9 month

I'm in Los Angeles, CA. Bought the car locally. Odometer read 98k miles. History suggests it was at least mostly a California car. It appeared to be well kept and in close to excellent condition

I changed the oil at exactly 100,000k on the odometer to top shelf synthetic at local Autzone: the Castrol Edge 10W-40 (did not "fluid titanium technology on the bottle, otherwise black bottle) at $9 something per quart. Oil change was done in September 2014 and oil was bought then. I did not check the bottle, but I assume it was the SN certified version.

The car is driven in severe conditions of the stop-and-go crazy LA traffic, with lots of short trips, and lots of WOTs.

Additionally, and it should be an interesting detail to you gearheads, this type of Mercedes likes to run hot. The red zone is at 125C and the owners manual explicitly states that everything up to that temperature is OK. Often times my car sits at 100C, and almost as often it hits 105C at which auxiliary fans come on at high speed and knock down the temp to 98C, which returns to 105C in several minutes of stop-and-go LA traffic. The oil MUSATB BE WORKING HARDER HERE and maybe that's why owner's manual specs for hot-only climates 20W-50 oil

Do note that 100C and 105C is temperature of the coolant, so oil must be even hotter at such coolant temps (so I think). Occasionally and in very dense, uphill traffic, if temp hits 105C and fans come on, the temp will continue to raise before being brought down by fans. I've seen as high as 110C.

Additionally I should note the WOTs happened numerous times at 105C and at 110C. The highest coolant temp I've seen is 115C in 95F weather, with 4 people in the car and A/C on, going uphill on the freeway at WOT at 95MPH.

Also the car has seen 140MPH a few times. And lots of 40mph-110mph freeway entrances on this oil.

So you get that the car runs hot and is driven briskly often with multiple WOTs. So how do you like my UOA and what are your thoughts on Castrol Edge 10W-40, which apparently is not even a premium formulation compared to other grades of Castrol!!!

Your thoughts on the subject and random, and comments are welcome! smile
Anyone know why Boron could be so high? Interestingly, BlackStone did not comment on it...


хос&#1...090;о

 

[Colt45ws]

Oil has sheared to a 30-grade. This doesn't seem to have affected wear at all, however.
The boron is part of the oil fomulation.
Looks like 6 or 7k miles might be the limit.
For as hard as you use it, and considering the owners manual recommendation, you might try running Mobil 1 15W50.

 

[Merkava_4]

Originally Posted By: Colt45ws
Oil has sheared to a 30-grade.


A pretty healthy 30 grade though...

 

[Ed_Flecko]

Originally Posted By: Colt45ws
Oil has sheared to a 30-grade. This doesn't seem to have affected wear at all, however.
The boron is part of the oil fomulation.
Looks like 6 or 7k miles might be the limit.
For as hard as you use it, and considering the owners manual recommendation, you might try running Mobil 1 15W50.


As a tutorial for me, what are you looking at when you say it has sheared to a 30 grade?

Thank you,
Ed

 

[aquariuscsm]

Your UOA looks great! I'd keep using this Castrol oil. If you want to try a 50 weight,I'd use the Castrol Edge 5W50. I prefer it to the Mobil 1 15W50 (which I've used both).

 

[Quattro Pete]

Originally Posted By: Ed_Flecko
Originally Posted By: Colt45ws
Oil has sheared to a 30-grade. This doesn't seem to have affected wear at all, however.
The boron is part of the oil fomulation.
Looks like 6 or 7k miles might be the limit.
For as hard as you use it, and considering the owners manual recommendation, you might try running Mobil 1 15W50.


As a tutorial for me, what are you looking at when you say it has sheared to a 30 grade?

Thank you,
Ed

Viscosity at 100C / 212F.

 

[bigt61]

UOA looks great. 8.5 quarts gives you a lot of wiggle room on what to use. 240F water every now and then is no big deal, oil was likely below 280F. The Castrol you're using seems to be doing fine IMO, although M1 15W-50 would also work. My big worry would be hanging on to my drivers license and my post speed trap insurance rate.

 

[KCJeep]

Looks good most 10w40's are going to shear a fair amount this one held up better than most. TBN is still very strong oil is nowhere near shot even under you severe use, trying 7,500 looks real reasonable from what I see here.