Well I finally got the opportunity to tow with my 6.7 today. I was very happy with the power towing the 5th wheel I bought. I noticed the oil temps were quite a bit higher than normal though. Usually, on the dash gauge, the oil temps are within 5 or so from the tranny temps.

I had temperatures climb up to the 230's and I pulled over to check it out. I could smell oil just barely, and I had just a few drops coming down, and had whipped around from the wind hitting it. Only like 3 drops dripped down onto the ground. I pulled over like 4 times, re-checking it, and checking the oil levels on the dipstick, and it appeared normal. I backed off towing by like 8 mph, and the temps were hovering about 215-220 then. It was only on a hard pull that they went up into the 230's.

Any ideas what might be the problem? It went down to completely normal temps once I got back into town, and was driving slow. Within 5 degrees of tranny temps. I was monitoring lots of things with Torque Pro while moving, and everything else seemed normal.

 

 

I recently had a oil leak like that on our 2015 6.7L, it was the vacuum pump and catch can for the PCV. Both were warranty items.

-Mark

 

Do you mean directly above the filter where it threads on? If so, it could be that during your last oil change, the gasket from the previous filter remained. Doubling up on a filter gasket will cause a small leak above the filter. If you don't think that's the case, then just put another 1/4 turn on the filter. It might be as simple as the filter not being tight enough...

As others have said, the oil temp is completely normal though. Wait until you hear your fan clutch lock at 235-240 if you think seeing high oil temps was shocking...LOL. The first time that happened to me on my 2012, I thought the trip was over...

 

And I have seen oil temps up around 248 while pulling 18000 lb up a 6-7% grade in 100+ degree ambient air temperatures. So what you are seeing is completely normal.

 

I have hit 248F several times on mine with steep grades and heavy loads. All Normal.


Clutch fan on high will sound like an airplane. All normal.

 

Okay I feel better about the temps now after seeing what "towing normal" is on this motor with all of yours. I definitely still need to find the source of the leak though.

I've had the truck since October, and it hasn't leaked a drop until towing for first time yesterday. I will be doing an oil change soon, and I'll snug the filter on good, I just don't think it's the source on my leak...

 

There was a fitting on early turbos that was prone to leak oil. Do you think your leak could’ve come from that high? As the others have said, your oil temps are on par with what I see towing.

 

I'm fairly sure now, I have the dreaded rear main seal leak! Truck has 113k miles. But it still doesn't make sense to me it only leaked when hot, under a load.

 

I would be much more suspicious of the turbo oil fitting as has been mentioned. They have a tendency to leak. I've repaired several and they usually make the bottom of the bell housing area very oily. If you climb up on the engine with a flashlight and small mirror you can get an idea if it's the oil fittings. If so it's not a huge job just make sure and replace the turbo coolant fitting also while you're there.

 

Thank you Willydmax!

 

No problem. If you do the work yourself give Autonation Ford from White Bear Lake a call for the parts. Can't beat their prices or service.

 

I agree with looking at the oil feed line to the turbo as those were common leaks and they will leak oil down the back side of the engine. And if you do replace that fitting go ahead and replace the coolant fitting since it's the same type and is prone to leak also.

 

Well I won't be tackling this work myself. I'll get the truck into the shop on Tuesday, and let them know the possible stuff, and go from there. The guys I use are very honest, and have never done me wrong. I'll report back what the problem is!

 

Do you guys think the turbo oil fitting, would only leak, if it was under HOT towing temps? Because that's pretty much the only time it has leaked, not a drop since then just cruising around town.