[gunthrek]

Greetings,

I recently bought a 2010 F250 Super Duty with the 6.4L and I've noticed oil spots accumulating under the places I park it. When I look under the truck, I don't see any active leaking, but the engine certainly has some oil residue in various locations and I'm imagining it's only actually leaking during operation and slowly dripping while it's parked. Not being very experienced with diesel engines, my understanding is that all diesel engines leak to some degree due to the positive pressure since it doesn't have a PCV system. My question is: is this understanding correct, does it only apply to the larger commercial engines or is it accurate for consumer grade trucks, and, if so, how much leakage is too much? Should the oil spots worry me, or do I just need to get used to it?

Thanks!

 

[RandomForumGuy]

Lost often its due to a poor front and rear main seal design. Ford sells an updated seal that fixes the problem but you have to drop the transmission to get to it. If it is just a seep then it wont hurt anything

 

[Chadwic]

More rare, but you could also could have the CCV mod vent to air. It wouldn't be pooling oil under the engine, but usually over by the passenger side. If so, check under your hood and see if your oil crank case is still connected to your cold air intake with the 1 inch tube or if there's a mod. They usually route it down by the exhaust or wheel well to mount along the frame below the passenger side. If they did that, you can always put a catch can on it.

 

[gunthrek]

So I haven't been back for a while, but I wanted to follow up with this question. I checked the oil a couple of weeks ago and it still read as over the full line even after a couple of months of driving it, though I haven't had an oil change since I bought it a couple of months ago, so I'm hoping the dealer didn't overfill it to compensate for the leak that I think they tried to hide. I'm getting an oil change in the next week or so, so I'll keep an eye on the level pretty closely after that once I know for certain it's been filled with the appropriate amount of oil.

The oil only seems to be showing up at the bottom of the engine, especially on the crossbars under both the engine and transmission, but I'm not able to really get under the truck to really locate where the oil is coming from. I always see very small single drops accumulating at the bottom of the oil pan, and also on the crossbars I mentioned, but I never actually see oil dropping from the engine...just wet spots on the ground combined with the old spots from where I parked it before. It looks like a lot of oil after a couple of months, but as someone who's not used to seeing oil under my vehicle, I may just be paranoid. My understanding is that a lot of diesels leak, so I'm just not sure how much is too much.

 

[Chadwic]

My understanding is that a lot of diesels leak, so I'm just not sure how much is too much.

While you certainly don't want any leak if possible, to put it in perspective a full oil change is 15 quarts. You can lose 3/4 of a gallon and still have 80% of your oil. What you're describing isn't something I'd worry very much about, but would still consider buying the UV kit and doing that myself if you're able. Try and clean up your engine, add the UV additive, and then trace it back to leak points with the UV light.

 

[Hydro]

Gonna have to get under the truck and search for the leak -- if you cant get under, then find someone else to do it -- a diesel should not leak any more than any other engine

 

[gunthrek]

While you certainly don't want any leak if possible, to put it in perspective a full oil change is 15 quarts. You can lose 3/4 of a gallon and still have 80% of your oil. What you're describing isn't something I'd worry very much about, but would still consider buying the UV kit and doing that myself if you're able. Try and clean up your engine, add the UV additive, and then trace it back to leak points with the UV light.

I didn't even know UV additives were a thing! I'll give that a try.

 

[GregWork]

It’s a 6.4L. Most leak somewhere. At least the 100 or so I looked at / crawled under did before buying a 6.7L
They also ‘make oil’ in stock form (regen fuel dilution), so it will read over full the further you get from an oil change.