Why is it leaking oil???

[xeninworx]

So my 2014 V6 3.7 is leaking oil. Not a lot but it’s leaking. Didn’t hit 20k on the odometer yet(almost at 19900). It’s leaking where the transmission mates to the engine above the oil pan. Sorry I don’t have pics.

I’ll tell you about the car so you have some perspective.

Bought it from a used car dealership August 2019 and the odometer read 12945 when I drove it off the lot. Dealership did an oil change on it before I picked it up. Don’t know what brand oil was used but there was a new Fram oil filter on there (I had seen the car the previous week and there was a different filter). Previous owner did 1 oil change at 8k which is the interval for these cars.

Drove to Montreal in October 2019 for thanksgiving and my nephews birthday.

I changed the oil when it hit 16k in November 2019 to get it back to the 8k interval. Used a Mobil 1 oil filter and Mobil 1 EP 5w20. Inspected underneath the car. Nothing. No oil leaks. Very little rust as the car was rustproofed twice by the previous owner at a Krown location. Car was fine.

Come spring this year, when changing back to summer wheels, I noticed some oil residue on the oil pan between the bell housing and motor. Not a lot. Just a little. Wasn’t sure what to make of it. Cleaned the area to see if it came back.

Last week, while installing the Steeda jacking rails, I noticed more oil again. Same amount. Just a little bit. It doesn’t drip onto the driveway as I’m always parked on pink inter locking bricks so I’d notice an oil stain.

Changed the oil today, same Mobil 1 EP 5w20 with a new drain plug. Cleaned up the area thoroughly.

I’ll keep an eye on it and see if it still leaks. Never had any issues until I changed to Mobil 1.

I was thinking it was the rear main seal but the engine is way too new for that to happen. I’ve only read of that happening to 1 person with the same motor and S197. Every other oil leak seems to be due from high mileage cars or leaking from somewhere else.

Did a lot of reading this evening, while I doubt it’s the rear main seal however it’s possible, I think it’s Mobil 1. Read a few people mention that it tends to leak through seals on however those were higher mileage than mine. It’s also possible Mobil 1 and the weight aren’t working out too well on this motor. I mean it is a 6 year old car.

You guys are more knowledgeable than me on these cars. Only had this car for a year so I’m still learning about it. What oil and weight should I try to see if it remedies the issue. Heard good things about Royal Purple and Amsoil for oil. Also what would be a good filter to pair with it?

[Stephen06GT]

For what it’s worth, 10W30 full synthetic, whatever is on sale, in my 06 GT. Didn’t burn a drop nor leak after 170000km. Roush supercharged motor swapped in four years ago, still running the 10W30 with the same results (over 180000km on the clock now).

[Ponyryd]

Most likely rear main seal. Cars are never “too new” to have failures like that, dealer techs fix new cars every day.

[xeninworx]

Most likely rear main seal. Cars are never “too new” to have failures like that, dealer techs fix new cars every day.

Yes it’s possible but I’m hoping it’s not. It’s a cheap part but not a cheap job to fix.

[LX89]

Check the PCV system.
If that's restricted it will build up pressure in the crankcase and cause oil leaks.

So many people have replaced gaskets without checking the PCV system and still had oil leaks afterwards.

Example,foxbody 5.0 lower intake manifold has a screen under the PCV valve that get's plugged up/restricted over time causing an increase in crankcase pressure resulting in oil leaks.

[xeninworx]

Check the PCV system.
If that's restricted it will build up pressure in the crankcase and cause oil leaks.

So many people have replaced gaskets without checking the PCV system and still had oil leaks afterwards.

Example,foxbody 5.0 lower intake manifold has a screen under the PCV valve that get's plugged up/restricted over time causing an increase in crankcase pressure resulting in oil leaks.

It’s clean. Not much in it. Cleaned it anyways while it was out. I should buy a catch can at some point though.

[xeninworx]

For what it’s worth, 10W30 full synthetic, whatever is on sale, in my 06 GT. Didn’t burn a drop nor leak after 170000km. Roush supercharged motor swapped in four years ago, still running the 10W30 with the same results (over 180000km on the clock now).

I’ve heard of people running 5w30 but don’t think anyone mentioned 10w30.

[Zippy]

Am I reading your post right, this car has only had 3 oil changes in 20k? and is a 2014?

[xeninworx]

Am I reading your post right, this car has only had 3 oil changes in 20k? and is a 2014?

That’s correct.

Autotrader ad at the bottom. Odometer when I stopped for Timmies down the street of the dealership.

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[Zippy]

Not trying to tell you what to do. But you should be changing the oil way more frequently. At LEAST once a year in my opinion.

[xeninworx]

Not trying to tell you what to do. But you should be changing the oil way more frequently. At LEAST once a year in my opinion.

Well the dealership that I got the car from did an oil change before I picked it up, August 2019. Then I did an oil change in November 2019. Last oil change was yesterday.

Maybe you’re thinking I’ve owned this car since 2014. I have not. Bought it last year.

[ZR]

What he's getting at, many people forget / neglect to factor time into their oil chance schedules.

[ZR]

Oil n filter = cheap
New engine = outrageously expensive.

[Scrape]

I usually change mine by mileage or date. In most cases I follow the date.

[ZR]

We are seeing a substantial uptick in regular maint neglect.

[xeninworx]

Well I’ve been working from home since COVID started so the car only got driven on the weekends as opposed to Monday to Friday. That’s why since I’ve owned it I’ve only put 7k on it. Would have more mileage on it if I had to go to the office. I did an oil change once a year when I had my Civic. That car is still going at over 240k on the odometer. The Civic and Mustang are on a 8k schedule so I always follow that. However since I’m working from home I’ll change it every 4k or year, whichever comes first.

I’ve got to go to work in the office this week but I’ll stop by Ford before heading into work and get Motorcraft oil and filter and change it this evening and inspect where it was leaking on the weekend. Not sure if I want to go with a blend or full synthetic.

[Laffs]

Am I reading your post right, this car has only had 3 oil changes in 20k? and is a 2014?

I think 3 oil changes in 8k is actually what I'm seeing. He bought with 12.9k and oil was changed then. Then again around 16k. And most recently at 20k.

[xeninworx]

I think 3 oil changes in 8k is actually what I'm seeing. He bought with 12.9k and oil was changed then. Then again around 16k. And most recently at 20k.

Yep that’s correct. Picked up Motorcraft Semi Blend and Motorcraft filter. Gonna change it tomorrow.

I’m also thinking I should do a coolant flush since it’s been sitting in the car for over 6 years now. Then transmission fluid and brake fluid will be next year when install the Brembo brakes.

Edit: Ford has changed their coolant to yellow, again.

[Ponyryd]

Yep that’s correct. Picked up Motorcraft Semi Blend and Motorcraft filter. Gonna change it tomorrow.

I’m also thinking I should do a coolant flush since it’s been sitting in the car for over 6 years now. Then transmission fluid and brake fluid will be next year when install the Brembo brakes.

Edit: Ford has changed their coolant to yellow, again.

Most likely 10-year coolant.

[xeninworx]

Most likely 10-year coolant.

I forgot I actually have the owner’s manual for the car. Says replace at six years or 160000 km, whichever comes first. Well, 6 years came first.

[xeninworx]

I’m thinking the additives in the M1 EP caused it weep oil. Had I used regular M1 I probably wouldn’t have had any issues. Changed the oil yesterday to Motorcraft semi-blend and Motorcraft filter. Gonna monitor it every month and see if it still weeps. The M1 did smooth out the engine tough as it’s a synthetic. When I used M1 EP in my Civic, I couldn’t even feel the engine vibrations.

Changed the transmission fluid yesterday as well to Royal Purple. Feels a little smoother. Not night and day but can tell it feels different. Would definitely like to get a Blowfish Racing support bracket to get rid of the clunkiness. Just doesn’t feel solid. In the Civic I used Amsoil MTF and that was like night and day. Kept the stock shifter in the Civic as I liked the stock throw. The Mustang has a shorter throw compared to the Civic.

Next is the coolant. I believe they have a shelf life which is why it’s recommended to replace by years also and not just mileage due to its contents. Gonna do drain and refills with 50/50 so the mixture stays the same throughout the process.

[xeninworx]

Okay, I think I figured out the problem. Back in January I installed a cold air intake and a BBK TB. Increased air means increased pressure. So now there’s too much pressure causing the oil to pass through the seals. I noticed some oil weeping on the back of the oil pan and around the cylinder head covers as well. Oil doesn’t leak on to the ground which means it’s only weeping while the engine is running because if it was a leak, well I’d see oil on the ground.


So I would need to decrease the pressure.

[xeninworx]

So changed the coolant today. Still not completely yellow yet so need more coolant but I found a easy way to do it if you’re not doing a flush and just want to change coolant.

Drive the car around until everything is hot. Park and cool down but not too long. Unplug the hose that leads into the reservoir from the water pump. Have the those go into some other empty bottle. It’s the coolant that’s run it’s course through the radiator and motor and back into the reservoir. Now start the car and the old stuff comes out of the water pump and fill the reservoir with new stuff. Since my old coolant was orange and the new coolant was yellow I could easily tell the difference.

[xeninworx]

Did a few things today.

Replaced hump hose reducer with a straight reducer.

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Replaced driver side hose with a 1/2” PCV hose. I did not like the way the stock one looked as it looked restrictive. Waiting on my Moroso catch can to come in to do the other side.

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And changed the coolant to Predator blood. This method worked perfectly. Kept filling the reservoir with Predator blood until all the old stuff was out and new coolant was coming through.

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[xeninworx]

Ever since I installed the Moroso catch can months ago the car is no longer leaking oil from anywhere. Problem solved.