HEMI Oil Leak

Aug 30, 2004
2020 Ram 1500 5.7, 12K

First discovered this oil leak around 7K. Dealer acknowledged the issue and replaced the oil filter adapter/cooler assembly. I cleaned the area very well after the repair, but the oil leak has returned.

I am not familiar with these engines. Valve cover gasket on that bank is bone dry. Cylinder head looks dry as well. Where else could it be leaking from?

Edit: upon further inspection there appears to be oil residue on a sensor that screws into the block. Oil temperature sensor?


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Does your truck have an oil cooler? Are those the cooler lines? If so, that may be the source. I would have the dealership add some UV dye to the oil and check it.
Looks like there is oil in the filter baseplate and possibly getting on the line because I see oil residue in there also.
Dang that looks pretty wet. The dealer will likely dye it to troubleshoot.

Personally, I don't trust dealers all that much and would probably dye it myself and lay under with it running.
I think you would see it pretty quick. You could probably record it for reference before dropping it off for repair.
Definitely looks like it could be the source. A leak lower down wouldn't explain the oil residue higher up. I wonder if this was the leak all along?
That is what I wonder. I looked this up in Tech Authority, I think it is called the "oil temperature sensor."

If it were me, I'd probably take as many photos as possible.

After taking photos, I'd spray something like Simple Green (or your other favorite degreaser) on the suspect areas, lightly wash/rinse, to get things as clean as reasonably possible. Drive the truck again and re-check for new leaks/seepage.

Take it back, exactly as it is, no cleaning, no dye, nothing. It looks like the oil temp sensor as already mentioned. Let them clean, it troubleshoot it, and fix it, it's under warranty. Out of warranty it looks like an easy fix. Having them do while under warranty takes all liability and responsibility off of you.
Dealer was unable to confirm origin of the leak, so they added dye and wanted me to return after a week to reassess.

Since I am waiting on parts for an unrelated repair, I asked them to keep the truck and drive it on my behalf.
Looks like there is oil in the filter baseplate and possibly getting on the line because I see oil residue in there also.
The filter is tight and I've cleaned the area multiple times and have tried different filters. Same result.
it could be the adapter seal

it’s under warranty so let the dealer do the diagnostics
Oil filter Adapter and seal were already replaced.

You have more faith in others than I. No way, no now, not ever will some dealership monkey drive my car.
No different than letting any auto shop drive your car.