Would you mind sharing a link or article that talks about cavitation erosion of the cast iron block that is NOT related to cylinder induced harmonics?

I'm looking to learn along with the rest, so no harm no foul here, ok?

 

Tom. It is my understanding that the proper test for the Delta is to operate the engine at wide open throttle. Pulling my camper up a mountain pass on a hot day I don't think was necessarily a fair test, so I don't want to put too much stock in the 24° deltas that I got that day. My only other chance to drive this truck other than short trips around town was to take it to that ski resort. It wasn't that steep of a climb and the truck was empty, and I didn't open it up so I thought that would be more of a fair test for the delta, but it still showed 18°. From what I read around here that seems like a large delta and pretty hot oil, considering the new components and fluids in my engine.

 

I believe the proper test for the delta is to have a warmed up truck (30 - 40mins of driving) then find a flat section of road, and while unloaded and not towing, hold it at 65mph and take your oil and coolant temp readings. That's where you want to see your 5* spread.

8*, 9*, 11*, or even higher spreads at much higher sustained speeds, or going up hill, or loaded, or towing, or all of the above should be expected and aren't a true reflection ....IIRC.

 

Colm,

My brand new oil cooler and clean coolant system gave me a delta of 9 to 11. I'm not sure where the 5 degrees came from, but it is commonly accepted that anything within 15 degrees is good.

Several of the ford techs on this forum have weighed in on the proper procedures to measure the delta. Most form members, including the tech's, agree the written ford procedure is ambiguous and not practical. Thus, most agree that a steady state condition at 60 to 65 mph is the best indication of oil cooler performance.

 

I don't doubt that you may have an partially blocked oil cooler I just thinking that it may not be that far out of line. The tests are confusing and conflicting IMO most Techs will admit that. when you drove home from this trip were your deltas the same or closer together assuming you had more down hill? I didn't mean to sound like a tool if it came across that way. don't want you to have to replace your cooler if it's not necessary but I understand not wanting to risk a major problem ether.

 

When I drove at 65MPH on the flat interstate here in Florida, my delta got
to 18* and I had the stock oil/egr coolers replaced BPD's versions and I monitor other things now with my SG2

So, IMO, IF you drive 65 MPH on flat terrain, not towing, etc. and your deltas are < 15 you should be good. The further below 15 is that much better.

As Piolet stated, under other conditions the temps will vary and you'll have no way to compare YOUR delta to other folks..



I believe the proper test for the delta is to have a warmed up truck (30 - 40mins of driving) then find a flat section of road, and while unloaded and not towing, hold it at 65mph and take your oil and coolant temp readings. That's where you want to see your 5* spread.

8*, 9*, 11*, or even higher spreads at much higher sustained speeds, or going up hill, or loaded, or towing, or all of the above should be expected and aren't a true reflection ....IIRC.

 

Damn I can't wait till my life slows down so I can spend more time on my truck!

Coming down the mountain, my WT was pretty steady at 188 and oil at 195-198. Still ~10 degree spread - with engine barely more than idling.

Still haven't had a chance to do a delta test per the suggestions here (hot/flat/65mph) - so that my numbers are comparable to others. Maybe I'm sweating over nothing here. Standy...
Hopefully this week.

 

You really need to find at least 5 miles of flat interstate to allow the temps to stabilize. I use a 4 mile streak after I've driven 65 for about 5 miles. The oil temps drop till about two miles into my flat run, then they hold steady after that.