Oil leak

RNLPFF

RNLPFF

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So, I am temporarily disabled due to a work-related injury, so I had to go to an establishment to get my oil changed. Upon getting my Jeep home, there has been a small leak since.

The oil drain plug has been checked for tightness. The oil filter has been checked for tightness as well. I did notice one loose bolt, and one missing bolt altogether near the large reservoir just behind the oil pan.

I tightened the loose screw and replaced the missing screw. FYI: It's a 2007 JKU Rubicon. I had her filled with 6 qts. of Amsoil.

Any suggestions? I posted pics below which show where the leak originates from. It appears to be the bolt nearest the driver's side.

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What are those bolts? Am I looking at the bell-housing on the transmission here?

Are those bolts suppose to have crush washers on them, because if so, those definitely aren't crush washers, which would be causing oil leaks.
 
I am so curious as to why they would be messing with the bolts on the oil pan or any bolts other than the drain plug if the only think you were needing was a oil change.

This is why i do all work myself. lol
 
Chris said:
What are those bolts? Am I looking at the bell-housing on the transmission here?

Are those bolts suppose to have crush washers on them, because if so, those definitely aren't crush washers, which would be causing oil leaks.
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I did buy this Jeep used. And, I agree - the middle bolt is the proper bolt as it matches the others around this area of the vehicle.

Can you tell me how these bolts and washers are causing the leak though? While there are two of these mismatched bolts, only the one on the driver's side is leaking.
 
IndominusHuman said:
I am so curious as to why they would be messing with the bolts on the oil pan or any bolts other than the drain plug if the only think you were needing was a oil change.

This is why i do all work myself. lol
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I agree. I hate letting anyone touch my vehicles because more often than not they will not handle the vehicles with the same care that the owner would. I just so happen to be disabled at the moment, so I won't be crawling under any Jeeps for a while.

Thank you all for your replies by the way.
 
RNLPFF said:
I did buy this Jeep used. And, I agree - the middle bolt is the proper bolt as it matches the others around this area of the vehicle.

Can you tell me how these bolts and washers are causing the leak though? While there are two of these mismatched bolts, only the one on the driver's side is leaking.
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I have zero experience with the 3.8 engine at all other than driving it. What are those bolts for? That's what I am trying to figure out.

If those are drain plug bolts, then the fact that they don't have crush washers on them is what's causing the leak.

However, if they are NOT drain plug bolts, then your leak is coming from somewhere else, likely the rear main seal or oil pan gasket.
 
I am a mechanical engineer and let me explain it in a simple term the best I can.
The wrong pitch diameter thread and/or angle of a bolt will register with a false torque into a cavity. It is just cross-threading the mating parts but is not tightening the assembly. So your tools will pick it up as torqued bolt but what it's reading is the pitch of the cavity port that is just being sheared. Machined cavities are not for galvanized hardware. The bolts for those machined parts are black tempered materials. See their difference here?

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Oscar-Mike said:
I am a mechanical engineer and let me explain it in a simple term the best I can.
The wrong pitch diameter thread and/or angle of a bolt will register with a false torque into a cavity. It is just cross-threading the mating parts but is not tightening the assembly. So your tools will pick it up as torqued bolt but what it's reading is the pitch of the cavity port that is just being cross-threaded.

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Yessir! That makes total sense. I never would have thought of that. I will have to find those exact bolts then. Thanks for such an in depth explanation. Much appreciated!!!👍🏾

Meanwhile, I had the mismatched bolt removed, and clearly the oil is coming from the bolt cavity at least.

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Chris said:
Looks like you found your issue then! It would appear that someone simply used the wrong bolts.
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Well, it appears that she is still leaking after replacing the bolt with an OEM bolt. Perhaps, I should be leaning towards the rear mail seal as the culprit.
 
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