Safe Oil Temp?
 

Main question is that if running a 203* vs 195* t-stat could cause premature oil brake down.

What is safe opperating temp of engine oil?

At what temp does the oil start to break down?

A quick google search yeilded these awnsers:
+Banks brand EOT gaudge show 170*-240* in the "green"
+From what i see most of our 7.3L run from 180*-220*.
+Also found someone stating that above 260* is bad. But its worse to run long time at 260, then a quick spike to 280*.

From this i gather that a 203* vs 195* T-stat is NOT going to affect the oil.
****But whats your guys thoughts on these matters?***

For a truck that is stock or mostly stock, it shouldn't be an issue.

Oil temps will depend on RPM's and engine load. As you said, engine oil temps will range. I've datalogged PSD's in winter and saw that driving on the highway engine oil temps struggle just to reach 170 degrees. Other's I've seen driving up a mountain pass in the middle of summer have oil temps reaching 210-220.

A big thing to consider with the 7.3L PSD... engine oil temps are taken at the HPOP reservoir. A truck with a modified HPOP system (such as two pumps), and having oil dumped back into the reservoir rather than down the front cover, will have higher engine oil temp readings. Simply because there's hotter oil at the reservoir, but cooler oil elsewhere in the engine.

Engine oil temps typically hover close to coolant temps for most conditions. So for most people, a 203 degree thermostat won't have any ill effects on oil longevity.

When I tow in the summer my oil temps reach 230 degrees.....I have to admit this has me worried, because the oil temp was at least 15 degrees lower before I installed my 203 degree. I fully trust Bob Riley and he's said the temps are where they should be.....I'm still leery. I'm planning on swapping back to OEM this spring; no good reason other than gut feel since I've chipped the truck. The older 7.3's with a 203 were factory set. In other words, their timing was affected by a chip.

I agree with you, Chief.... Not a big fan of EOTs getting that hot. I've never seen over 200, but I don't tow heavy either, and I have the factory 192 deg stat. I was thinking of putting a 195 back in. In "normal" driving in the summer, I will see the EOT get to 192, but no hotter, so I know the stat is pretty accurate. Towing a fairly light load (~7k) on the highway in the summer at 70mph, it got to 198.

In my experience and research most premium oils will with stand 300 degrees F. After that they start to break down rapidly and do bad things inside the engine. I have run stationary engins to that limit and had no ill effects. Just don't push it. There were some hi temp lube oils available for gas turbins ( jet engines) if you really need it, but the costs are high.

PWRPROD

How does putting the sender in the HPOP compare to by the oil filter? Will there be a tempurature diifference between the two locations? What is the ideal location for sampling EOT?

Given that you have a turbo with oil going thru it that will reach much higher temps, and the oils used in these engines are designed for that...I don't think 220 or 260 is a big deal at all

I wouldn't want it much over 220. The 6.0s seem to start developing high pressure leaks around 230, so I imagine it wouldn't be good for our trucks either, even if our high pressure leaks are easier to fix :-X04

Good question Walt. I was going to put my aftermarket EOT sender in that 1/4" plug spot at the filter housing. Do you know which way the oil flows through the oil cooler? Away from the filter or toward the filter?

The oil goes directly from the pump through the oil cooler and filter and out to the engine. So at the filter you will be reading the temperature immediately after the cooler.

Not sure, I was hoping to gain some insight from this thread

Hmm, sampling EOT of at the HPOP may be more accurate.



Joe care to share where you are sampling EOT ? Was an adapter required?

Thanks!

Thanks Clux. :-X22

I would be willing to bet Joe is reading it on his Scan Guage which is the same as the PCM, at the HPOP.

Sent you a pm Robin^^

mine reads no more than 210f at the scan guage but runs reguarly 230-235f towing on my EV2 which the probe is by the oil cooler...