I was on my way home today with my trailer out side temp around 86F, I was climbing a grade in 2nd gear @ around 4700rpm. Trans was doing good peaked around 198F but my oil temp shot up around 253F when I got to the top. How bad is that?

 

That's getting up there. Wouldn't want it there for long, that's for sure. How long was it at that temp? A minute or so is not detrimental, but don't keep it up. You didn't hurt anything so don't sweat it. My personal no **** pull over and stop temp is 260. You didn't hurt the motor, it'll just start cutting into the usefull life of the oil. How are you monitoring oil temp? Not too many guys I know of besides me have a real oil temp gauge.

 

It was @ 253 for about a minute and 1/2, New oil too (Motorcraft 5w20). The temp reading is off the edge programmer, no sure where its pulling the temp from. Maybe the pan?

 

to the best of my knowledge, only 2004 and early 2005 trucks have oil temp sensor in the pan. i believe the newer ones are somewhere around the filter.

 

I know this is getting away from towing and there has been lots of discussion on this topic, but would running a 5w30 help drop oil temps or maybe a 5w20 full synthetic. Cold is not a factor here in southern Cal. with the heat and all the hills.

 

A 5W30 will possibly raise the oil temps (more friction). The only full synthetic that would possibly make a difference would be a very expensive PAO-based one such as Amsoil.

 

The Motorcraft oil is tested for hours at 302F and is not allowed to "break down" in that deposits are limited as well as any movement of the viscosity. If you have the newest GF-5 oil in the engine, the testing is even more tough especially any gassing of the oil or add pack. Your engine is fine and so is the oil. No synthetic on the market is going to help. Using a "thicker" oil only adds to the heat as a thinner fluid gathers and releases heat faster. In the old days we used a 15w-40 for high heat and heavy towing because of fuel dilution from the carbs. Obviously, you don't have a carb so the thinning of the oil from the fuel is not an issue.
FWIW, Amsoil is no longer a PAO only based oil. They've been reformulating over the last two years and finally settled on a blend of PAO and Visom from M/E, which is a GP III+. Still as strong as it always was but the cost of PAO base oils has gotten to the point where no oil maker can afford to sell it and still have customers. If you want or need extended oil changes, Amsoil is as good as it always was. It's just not worth the price for the average driver.

 

I know Amsoil has expanded their line of oils - but are you saying that even the top of the line Signature oil is reformulated too?

 

Correct me if I'm wrong, but the XL oils is the current line that was reformulated and it is the XL line that is a newer group III+. The SSO, ASM, and the like should still be pretty much unchanged and a PAO. This has got me to thinking though and I'm really considering going with that new XL in my new truck (if I get one!)

I would make two arguments but no one around here will ever consider them...all you brainwashed MC guys

--The new OE oil is going to be as good as any 'synthetic' on the market and is also competitively priced.
--The new XL is every bit as good, if not superior to, the famed MC 5W20 blend without all the extended drain interval hype you guys don't like to talk about. ESPECIALLY with 7,500 becoming the norm for Ford!