Something odd, insight is welcome

[jaynissan12]

Ok, I have a '14 Ram 3.6L 8 speed, I did the first oil change at 1100 miles. I used the recommended 5w20 and went with Havoline Syn. since O'Reilly's was having a sale at the time with a Wix cartridge filter. This engine is set up to allow oil and coolant to come up to temp quickly and maintain around 200 F. I would notice a hot oil smell after the change but never saw a leak anywhere so I just ignored it, it wasn't strong, just noticeable on a warm day outside the cab.

Fast forward 4000 miles and I decide to give it a second oil change ( I tend to change oil early when the miles are low), going with the same filter, but I went with 5w30 QSUD that I had on the shelf for a little less than a year. Chrysler does allow the 5W30 as long as it meets their spec.

Ok here is the odd part, I figured out why the hot oil smell appeared last time, the O Ring for the filter cap was in the wrong place, was very surprised it did not leak out some. So I put the new ring on and made sure it was still in place as I tightened down the oil filter cap. Now the way my engine and trans reacts to torque and throttle improved. Trans shifts smoother, engine hold high gear better on slight inclines. I don't believe a change in oil grade could have made that much of a difference, but I can't say that for sure.

So here is a question for those who have good technical skills and understanding, would a poorly seated O ring that was obviously leaking vapor cause such a change? BTW I noticed my oil runs about 15-20 F cooler now too.

 

[zach1900]

Filter cap, as in oil filter?

 

[jaynissan12]

Yes, this uses cartridge filters so it has a oil filter cap that you replace an O ring on when you replace the filter, all this is located near the throttle body and air intake plenum.

 

[redbone3]

Seems a little strange. One would expect it to lose oil from a unseated O ring, not just vapor.

 

[Greasymechtech]

Some filter cap/mount/housing/plumbing/drain/adbv/bpv all-in-one setups need to be properly seated to work.

Oil was either bypassing the filter, or not bypassing the filter, draining back or not draining back....when required.

You'd have to map oil flow out to see what happened and understand it.

 

[jaynissan12]

Exactly my thoughts. Now the other stuff like change in performance after putting it on right the next oil change and the oil running cooler (190 instead of 215 F) it really makes me wonder if the better seal affected some sensors in the correct way or the bad seal releasing vapors would cause a slow down in the filter function leading to performance lost and higher temps? I dunno, curious if someone has ever experienced a similar change in performance like that with something so simple.

 

[jaynissan12]

That's good insight Greasy, and I do believe you are onto something as that can explain the higher oil temps and possible performance robbing that might have been going on. Sounds plausible.

 

[Doog]

I think your engine broke in a little bit after 5000 miles and the oil filter had nothing to do with it.

 

[oldhp]

I have same exact truck/engine/trans combo. To me if it leaked vapor it should have leaked oil. Air intake is no where near the oil filter cap. I painted a mark on the oil cap/canister, when changing oil I line up the marks and stop. Torque plastic??? The way the o-ring is on the oil cap it doesn't need torqued, just seated. Just me.

 

[JHZR2]

Once I accidentally left the oil filler cap off on my S-10's V6. It ran like usual.

On my 318i, cracking the oil cap would make the engine stall.

So the oil cap is some level of vacuum leak, I'd suppose different on all vehicles.

So I'd guess if the oil filler cap had a slight leak, it was generally compensated for by the icv or other mechanism, but now that it's sealed well, the ECU is re-learning.

 

[jaynissan12]

Originally Posted By: Doog
I think your engine broke in a little bit after 5000 miles and the oil filter had nothing to do with it.

While you are correct in a sense, in another that's not going to be an overnight change.

 

[jaynissan12]

Originally Posted By: oldhp
I have same exact truck/engine/trans combo. To me if it leaked vapor it should have leaked oil. Air intake is no where near the oil filter cap. I painted a mark on the oil cap/canister, when changing oil I line up the marks and stop. Torque plastic??? The way the o-ring is on the oil cap it doesn't need torqued, just seated. Just me.


It should have but didn't. It is actually party underneath the air plenum, not the air intake. Anyways that doesn't matter. I didn't torque mine, just used a rachet until it wouldn't go any more without forcing it, you can hear it compress down on the O ring. Good idea on the marking, try that next time.

 

[jaynissan12]

Originally Posted By: JHZR2
Once I accidentally left the oil filler cap off on my S-10's V6. It ran like usual.

On my 318i, cracking the oil cap would make the engine stall.

So the oil cap is some level of vacuum leak, I'd suppose different on all vehicles.

So I'd guess if the oil filler cap had a slight leak, it was generally compensated for by the icv or other mechanism, but now that it's sealed well, the ECU is re-learning.


Makes a bit of sense actually, I guess a vacuum leak could occur on the filter cap if not sealed or seated good enough.