Engine oil max operating temp ?

[Canuck Dennis]

seen ad on TV this am from Mobil oil, seemed to indicate the oil was good for 500 degrees operating ??I thought 140 was was the safe max ?

 

[MikeP]

The owners manual for my 1989 Ferrari 328 states that if the engine oil temp exceeds 240F you should slow down. I saw it get to 210 out in the NV desert at 140+MPH (track near Vegas) and ambient temps of 108F.

 

[Canuck Dennis]

Ahhhhh, new I missed a hundred or so there...

 

[gbharrington]

Here is my synthetic oil story.
Before I discovered the joys of boating I was deeply involved in auto racing. In the early 90's I ran a 60 mile road race in a car with no coolant in it (long and painful story). This was a 4 cylinder engine than ran @ 9800 rpm. I was using Valvoline 5W-30 synthetic. I lead the race for all but the last 2 laps because it started to misfire due to the distributor cap starting to melt. The oil temp gauge was pegged at 280 from the second lap on. I ended up finishing 4th and pulled to the side of the track after the checkered flag. Still running and good (not great) oil pressure. When I tore the engine down, the pistions were a little scuffed, but the bearings and other wear surfaces were fine.
I became a believer then and there!

 

[MikeP]

Yep! Syn Oil is so much better than dino oil that I can't even understand why Dino oil is still in use.

I used to build competition/racing motors and we discovered in the late '70's that Syn oils reduced wear AND increased HP on any engine. For example, on a Mopar 426 hemi SS motor, switching to Mobil 1 syn 30 wt over dino 30 wt gave you a 10HP increase for FREE! Sure, 10 HP on a 600-700+ HP motor (700 HP at that time, now they make around 1000 with the same motor) isn't much but if YOUR race car has 10 HP more than the other guys identical race car…you win!

 

[Canuck Dennis]

I guess the DD 2stroke guys are stuck with the usual 40 w minimum cf2 spec.

 

[REBrueckner]

I read somewhere that the straight 40 wt in my Allison tranny with 8v71TI's was limited to about 210 or 220 degrees...

but I don't recall if that was tranny or an oil limit.....

I do remember that my tranny oil ran at about 185 degrees at about 1800 engine RPM....I put
on temperature gauges with helm readouts....

 

[Glory]

220 is a likely reliable number.

syn oil is a made from crude oil.

JM