Differential axle seal is leaking

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2022 CX-5 Turbo
Went to dealer for oil change today.
The advisor told me the differential axle seal is leaking (a wet spot, according to him).
It is leaking very very slowly, but he ordered the parts ($700 job according to him) for me to go in next week. It is covered under powertrain warranty. Thank God!

Guys, keep an eye on yours if you got an AWD.
 
Went to dealer for oil change today.
The advisor told me the differential axle seal is leaking (a wet spot, according to him).
It is leaking very very slowly, but he ordered the parts ($700 job according to him) for me to go in next week. It is covered under powertrain warranty. Thank God!

Guys, keep an eye on yours if you got an AWD.

Thanks for the heads up, will do. Did he mention any TSB on that or anything, or just bad luck?

That's almost a blessing in disguise: you get new differential fluid and don't have to pay for it!

This is very true!
 
The thing is that I already spent $ on replacing the differential fluid at 30K.
According to the advisor, leaky differential axle seal is very rare on CX9.
 
Well, both seals (apparently there are two of them) replaced by technician.
$0 out of my pocket. They gave me a loaner Mazda3 for the day. I paid for gas I used.
 
I have 43K on it now.
I don't know. I suspect that the guy who did my differential fluid change probably has something to do with
the leaky seals. Who knows? I did that at 30K. Now, they told me there was a small leaky spot....
Anyway, I don't think this is a common issue, AFAIK.

The thing with BMW is that they break down after warranty (4 yr/50K).
Before my warranty expired, I ran into a couple issues only (cam position sensor - wouldn't hold idle,
and coolant temp sensor - the needle was all over the places). At about 55K, all hells broke loose.
The entire coolant system components had to be replaced one after another. This went on for about 20K miles.
I went in and out BMW dealerships like every two weeks.
I just read the Yahoo article a few minutes ago. It says that BMW is more expensive to own used than new (even if you factor in the depreciation).
So true. If you want to own a German, lease one, don't buy one. At the end of lease, return it. Adding the free maintenance program
of BMW, you only pay for the gas and depreciation. Very simple.
 
Same thing happened to my 2010 AWD at around 7,000 miles. There was a damp ring around the right side rear seal where the rear axle enters the differential. The leak was slow enough that nothing was actually dripping on the ground, but a coating of gear oil was spread all around the adjacent areas. The dealer replaced the seal without charge.
 
I just notices a few grease spots on the garage floor today. The wife is out of town with the 9 at the moment so I'm going to have to check it when she gets home. I had to have just started because the spots weren't there a few weeks ago.

Wife got back and I checked. The passenger side oil seal appears to be leaking. I scheduled it in for repairs. See my further comment below regarding a TSB about this problem.

2007 GT
 
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For us 2007-2008 owners, we probably need to check the seals.
They are covered by powertrain warranty, so make sure you have them replaced by 5yr/60K!
 
Bend over, here it comes: Mazda has issued TSB 0300411, 9/21/2011 which basically states that vehicles from 2007 - 2011 may have issues with oil seals leaking because of a problem in the design and placement of the differential breather. The recommended fix: replacing the differential with a new one having a different breather design. Glad I bought my MEPP service contract. (boom06)

'MAZDA Some CX-7 and CX-9 crossovers may leak oil from the rear differential seal. In T.S.B. 0300411 issued on Sept. 21, Mazda said the issue with 2007-11 models might be a differential breather that was placed too low and became clogged by snow or water. A new differential with a raised breather covered by the breather boot should stop the leak.'
 
Does the newly issued TSB calls for new differential? (which costs > $700 installed)
 
The section in quotes in my post is as much as I can find on the subject doing a Google search for the TSB number. The actual TSB isn't posted anywhere that I can find. The statement implies that a new differential, with a revised breather configuration, is the fix.

Why they'd say replace the differential is beyond me. The breather is serviceable part costing around $10. It sits on the top, right side of the axle housing. The entire differential is a $2021.00 item.

Anyway, mine is going in on Friday to have the leaking seal replaced. I'm going to ask about the TSB then and see what the dealer has to say about it.

[edit]

Dealer replaced both of the seals in the differential and it only took them about 90 minutes to do it. That means they dropped the differential to do the work. So, the $700 estimate for labor to do this repair is way too high. Even if you assume a $100/hr shop rate that would only be $150 - $200 labor and the seals are around $15.00 ea. Even based on flat rate it would be a big stretch to get to $700.

Service writer told me that they've done several of these replacements. The service writer didn't have any any comment about the recent TSB on the seals and breather.
Since mine was still within the drive train warranty it didn't cost me anything. The MEPP service agreement covered the cost of the rental car I had for a half day. So, I had no out of pocket for this repair.
 
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Yeah that is pretty crazy. Along those lines, the TSB for the brake & steering wheel shake over 45mph states to replace the rotors and NOT to re-use the wheel bearings..but rather replace the bearings (at like several hundred a piece). If bearings are not symptomatic and rotors are warped, they have no reason to tell dealers to replace the bearings other than added revenue. It is certainly not standard practice to replace wheel bearings whenever you put new rotors on.

fyi, all data does not have the September differential TSB yet. Will post it once it becomes available.
 
...Joining the leaky seal club.

All of a sudden we noticed a burning smell coming from the rear of the car. So, I jack it up and took a look. Oil coating all over around diff. So, I wanted to make sure the oil wasn't too low. I got the filler nut loose and slowly took it out then by hand, and the whole time I hear a HISSING noise. The diff was actually pressurized by what I think (after reading this thread) a plugged breather. The oil was actually sort of bubbling out between the threads of the plug and hole. I'm going to try a cheap fix and replace the breather. Maybe the pressure gets so high that it is forcing the oil out because it is more than what the seals can take and the seals are actually ok. I just don't see both seals going bad at once, unless they are designed to fail at 60K. Currently have 63K clocked on it.

So, I'm going to obtain a breather and see what happens. Hopefully I can help some others on here.

btw I added about a 1/3 quart of oil to the diff to fill it.
 
I got the seals replaced 2 days ago and so far no smells are apparent. Here's a pic of what I got for the record:
b01.jpg


and here you can see that the old one is rusted inside under the cap.
b02.jpg


I took the old one apart and under that cap is a spring and rubber seal. Once the pressure gets to a certain point it overcomes the spring and lets the pressure out. I took the old one and tried to blow air through and I couldn't. The new one I could blow air through fairly easily. After taking the cap off the old one and getting some of the dirt and rust out of the way it seems to work a little better. It still wasn't as good as the new one though.

I installed the new breather and drained and filled the rear diff. Its been two days and no smell as of yet. Will keep you posted of my results.
 
Just got back from having my 2008 CX9 serviced and to check leaky diff seals. Bad news, both seals are leaking and need to be replaced. Dealer told me it was going to be $1600 for parts and labor.....WTF!!!! (bang) I just about to roll onto 110K miles and no extended warranty. What is all this chatter about TSB 0300411, 9/21/2011?? Is Mazda honoring this?
 
Just got back from having my 2008 CX9 serviced and to check leaky diff seals. Bad news, both seals are leaking and need to be replaced. Dealer told me it was going to be $1600 for parts and labor.....WTF!!!! (bang) I just about to roll onto 110K miles and no extended warranty. What is all this chatter about TSB 0300411, 9/21/2011?? Is Mazda honoring this?

Yes, if you pay for them to do it. a TSB is not like a recall, it justs helps the dealer fix something more efficiently. My fix I posted above works, but not completely; oil still leaks - just very little. I'm still running mine, haven't replaced the seals and it is still fine. I checked the oil level just the other day and when I took the fill plug out the oil ran out of it, so it was still full obviously.
 
Just got back from having my 2008 CX9 serviced and to check leaky diff seals. Bad news, both seals are leaking and need to be replaced. Dealer told me it was going to be $1600 for parts and labor.....WTF!!!! (bang) I just about to roll onto 110K miles and no extended warranty. What is all this chatter about TSB 0300411, 9/21/2011?? Is Mazda honoring this?

$1600 seems like a lot to replace the seals. I would check a local garage for an estimate and get a second opinion.
 

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