Maintenance surprise on a 2009 - Rear crank seal and Valve cover gaskets leaking

[jetstream23]

During routine maintenance at a local independent shop the technician reported the Rear main seal (crank seal) and valve cover gaskets leaking. How common is it for a rear crank seal to leak and need replacement? Vehicle has approximately 170K miles on it and has been driven primarily in the dry southwest for 10+ years. A search of "rear crank seal" didn't yield much here in the 200-Series forum. Thanks.

 

[clrussell]

Do the valve cover gaskets first.

Rear main looking leak might be valve covers running down.

Replace the pcv filter too

 

[TLC2013]

The rear main seal is not common at all. I would do the valve covers and check for the cam town leaks while the mechanic is in there. Afrerwards do a thorough cleaning and moniter the area by the bell housing to see if the leak shows back up. The RMS are usually very slow to leak and take significant time to progress.
I was one of the lucky ones here who had to replace the RMS. I dont think more then 3-5 members have ever reported this as an issue.

 

[jetstream23]

Thanks guys. Yes, it seems very, very uncommon. Appreciate the suggestions.

 

[TLC2013]

Here is what mine looked like. Super slow and small leak from the bellhousing

 

[04UZJ100]

Swap to 5W30 and see if it stops.

 

[TLC2013]

Swap to 5W30 and see if it stops.

Lol I am cracking up, you have me thinking of this meme


wouldn't hurt to try and switch to 5w-30 and may want to give the high mileage a shot. I like the valvolene full synthetic. Beats spending $2k on the seal and labor.

 

[bloc]

@jetstream23 has your PCV valve been changed? If not it is plausible to be contributing or causing all of this. Under $10 for the part and quite easy to do

If you want to do some searching try "rear main seal" instead of rear crank seal. Much more common terminology.

Also I'd avoid "high mileage" oils like the plague. They typically include seal swelling chemicals that make rubber parts swell to slow leaks. The problem here is in swelling, the density goes down, which means they get softer, which means they'll wear out even faster.

Lol I am cracking up, you have me thinking of this meme


wouldn't hurt to try and switch to 5w-30 and may want to give the high mileage a shot. I like the valvolene full synthetic. Beats spending $2k on the seal and labor.

View attachment 3408523

Thank you for this

 

[jetstream23]

Swap to 5W30 and see if it stops.

5W30, 10W60....whatever it takes!

 

[TimCFJ40]

I am fairly certain that my 2008 has a rear main seal weeping at 272k miles. It is down less than a quart at 5000 miles, and doesn't even make a drip on the driveway, so I haven't worried about it. A weepy rear main seal will not hurt anything as long as you don't let it run low on oil. And with 8 Quarts, you have a good bit of margin...

Mine looks just like @TLC2013 's picture above

 

[tbisaacs]

So I had similar leak and had valve cover gaskets replaced and turns out it was cam tower leak. I have yet to address it as it's extremely slow leak. Could this be your issue? Oil running down the block and toward the back?

 

[jetstream23]

This is why I come here. Great suggestions, fellas. I'm having the valve cover gaskets replaced and the PCV valve checked. Will get the area cleaned up and then monitor for any additional leaks that might lead to the Rear main seal or Cam tower. I too haven't seen any signs of oil on the garage floor where the LC is parked daily. Also, during the oil service there was the normal volume of oil that came out when drained, so whatever is leaking seems to be very slow.

 

[TheComedian]

Lol I am cracking up, you have me thinking of this meme


wouldn't hurt to try and switch to 5w-30 and may want to give the high mileage a shot. I like the valvolene full synthetic. Beats spending $2k on the seal and labor.

View attachment 3408523

Or at least a not too small amount of grease
That is what I did when I noticed some leaking on the rear diff when I was in the middle of nowhere in Marocco