2018 CX-5 Oil Leak? Is this TSB for Tensioner?

Sent my car to dealership to have them check oil leak (and referenced the tensioner oil leak issue TSB # 01-019/19. After a "thorough" inspection, they said they couldn't find any oil leaks but replaced the tensioner anyways. I tried not to roll my eyes and decided to send them pictures. Has anyone else had this issue?

From the TSB: "Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed.

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Sent my car to dealership to have them check oil leak (and referenced the tensioner oil leak issue TSB # 01-019/19. After a "thorough" inspection, they said they couldn't find any oil leaks but replaced the tensioner anyways. I tried not to roll my eyes and decided to send them pictures. Has anyone else had this issue?

From the TSB: "Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive belt auto tensioner damper when the auto tensioner fully operates under both high ambient temperature and high load conditions. To eliminate this concern, the shape of the drive belt auto tensioner damper has been changed.

Pics attached and one in line:
View attachment 298038
This leaky belt tensioner issue has been discussed many times here. It’s a very common problem for CX-5, and as you noticed, there’s a TSB for it. Here’s one long discussion for the problem:

Belt Tensioner - Shouldn't this be a warranty item?

And here’s what my leaky belt tensioner looks like on my 2016 CX-5 at 41,150 miles:

E1070CC8-BCC6-4D2D-8EC5-DE806AE795AC.jpeg


But there’s not much oil inside of the belt tensioner. A leaky belt tensioner can only make itself wet, but not capable of dripping much oil down like your pictures showed. Yours looks like having timing chain cover leak, which is another lesser common issue for CX-5 and there’s a TSB for it too.
 
Read up on the timing chain cover issue. Sounds like a real hassle to fix. I'm in a little disbelief that the master tech at the dealer said they didn't see any leaks today when they had it.

What do you all suggest? Try to get if fixed under warranty or let it go?
 
Read up on the timing chain cover issue. Sounds like a real hassle to fix. I'm in a little disbelief that the master tech at the dealer said they didn't see any leaks today when they had it.

What do you all suggest? Try to get if fixed under warranty or let it go?
If I were you I’d definitely bring the TSB (although the timing chain cover leak TSB doesn’t include the 2018 CX-5) and ask for the oil leak repair if your 2018 CX-5 (how many miles BTW?) still has new-car warranty. Not saying the powertrain warranty won’t cover oil leak problem, but you’ll never know there may be some surprises or excuses by lesser powertrain warranty coverage. I’d try a different Mazda dealer with better reputation and reviews if that’s an option. I’d also contact Customer Experience Center, Mazda North American Operations sending the evidence of oil leak with pictures, and ask for help to fix the problem as the Mazda dealer you visited has failed to help.

TSB No.: 01-018/18 OIL SEEPAGE AT ENGINE FRONT COVER

On the second thought, you may not want to tell the dealer at front what the oil leak problem is coming from (such as you mentioned the belt tensioner, but apparently that’s not the culprit). Just say please fix the obvious oil leak problem, period.
 
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Thank you yrwei52. Car has about 24K miles and about 1 month of the 3 year warranty on it. I sent the car back to the dealership today along with pics. If no good progresss, customer experience is a great idea. Thank you!
 
Read up on the timing chain cover issue. Sounds like a real hassle to fix. I'm in a little disbelief that the master tech at the dealer said they didn't see any leaks today when they had it.

What do you all suggest? Try to get if fixed under warranty or let it go?
First you would need to confirm there is actually an active leak with the new tensioner in place. Clean the entire area to a like-new appearance, and take multiple pics of all of it in that condition. Then monitor for signs of leakage/seepage, particular at the gasket (use an inspection camera for gasket areas that you cannot otherwise see). If anything does start to show up, wait just a bit until it's significant enough so that even your stealership cannot refute the before and after visual evidence.
 
First you would need to confirm there is actually an active leak with the new tensioner in place. Clean the entire area to a like-new appearance, and take multiple pics of all of it in that condition. Then monitor for signs of leakage/seepage, particular at the gasket (use an inspection camera for gasket areas that you cannot otherwise see). If anything does start to show up, wait just a bit until it's significant enough so that even your stealership cannot refute the before and after visual evidence.
IMO since OP’s CX-5 still has bumper-to-bumper warranty, he should let his Mazda dealer do all the hard work you stated finding the leak.

With the amount of oil leaked based on the pictures shown, the leak definitely is not from belt tensioner, although his tensioner itself could have been leaking too otherwise the dealer wouldn’t replace it in the first place.
 
unfortunately most 2018 models suffer from both tensioner (not so bad) and chain cover leaks (worse). two separate issues. Sometimes the oil control valve too goes bust as well but that is on top of the engine.
I got all three so far. The chain cover leak I got early in the first year like 5k mile or so. The tensioner I noticed at the 2nd year.

My suggestion as well is to get the dealer to fix everything that is leaking oil. Thats why you have warranty. The chain cover leak fix needs the car to stay at the dealer at least a day for the new sealant to cure + its a lot of work.
 
IMO since OP’s CX-5 still has bumper-to-bumper warranty, he should let his Mazda dealer do all the hard work you stated finding the leak.

With the amount of oil leaked based on the pictures shown, the leak definitely is not from belt tensioner, although his tensioner itself could have been leaking too otherwise the dealer wouldn’t replace it in the first place.
Although I would agree with you that's the normal approach, it's this from the op which caused me to write what I did.

... After a "thorough" inspection, they said they couldn't find any oil leaks but replaced the tensioner anyways. ....

In this case I'd much rather do a relatively small amount of work up front, rather than waste my time with this outfit. But it sounds like the op has already sent the vehicle back, so it's a moot point now. And I've been wrong about stuff like this in the past, and perhaps they will act upon what the op says and move forward with the repair. However, my betting money would be that they hand the keys back and say 'no problem'.
 
Dealer confirmed timing chain cover leak. Stated they assumed the oil stains on the plastic shield was left from sloppy oil change :rolleyes:. Although they are friendly and have a convenient valet/loander program, I've needed to do a lot of the research / suggestions on my own. Otherwise, they just say everything is normal.

They are ordering parts. Need ~2 days once parts arrive to fix. Said they would drop the engine to do the repair. Yikes.

Any suggestions on what else to check before my bumper to bumper warranty expires?

  1. Have had the cylinder deactivation and the surging at low speeds PCM fix.
  2. The tensioner fix.
  3. They said they did the "fix" for the squeaking rear brakes, probably just some grease or shims.
  4. Oil control valve does not seem to be leaking.
  5. No ticking noise from engine (though it's always in a garage above freezing.)
 
Dealer confirmed timing chain cover leak.
Good news!

Said they would drop the engine to do the repair. Yikes.
Bad news!

Based on reports here and the TSB, engine drop isn’t needed to remove the timing chain cover! I hope the tech who is doing the job at your Mazda dealer knows what he’s doing! The tech only needs to follow the procedures outlined in the TSB closely to avoid the screwups!
 
..

They are ordering parts. Need ~2 days once parts arrive to fix. Said they would drop the engine to do the repair. Yikes.

....

Either this was for shock value "Hey we are a great dealership, we are going to do ALL this work for you, our awesome customer"

and / or

The dealer service writer simply does not know what they are talking about.
 
I was suprised about engine drop. The guy said they didnt think they had enough clearance to access everything. I sent them the TSB. Anyone in Central MA had this done? Which dealership did you go to?
 
⋯ Any suggestions on what else to check before my bumper to bumper warranty expires?

  1. Have had the cylinder deactivation and the surging at low speeds PCM fix.
  2. The tensioner fix.
  3. They said they did the "fix" for the squeaking rear brakes, probably just some grease or shims.
  4. Oil control valve does not seem to be leaking.
  5. No ticking noise from engine (though it's always in a garage above freezing.)
Looks like you’re familiar most of TSBs、SA’s and recall related to cylinder deactivation. I’d try to rev the engine up to 5,000 rpm for 20+ seconds while driving on the highway with lower gear in manual mode making sure all rocker arms are in right place. Search the forum for this experiment.

Honestly I’d prefer my 2018 CX-5 is having ticking noise so that I can get revised HLAs installed if I were you. ;)

I myself collected as many related TSBs as possible for my 2016 CX-5 and brought them up to my Mazda dealer 2 weeks before the new car warranty expires. Luckily the master tech agreed to replace my rear brake calipers with revised ones based on a TSB for brake dragging issue, after the first tech said they’re normal.
 
changes13,
Make sure they change the oil as well after the procedure. As far as I recall the oil pan is removed and re-sealed as well in the process. Along with the timing chain cover. It is a pita job in any case to work on this leak.
Often times they re-use the same oil which to me is bad practice. Good luck.
 
I was suprised about engine drop. The guy said they didnt think they had enough clearance to access everything. ...
Yes, really bad news to need an engine repair as significant as this one will be. And I have to say that it's unsettling to have them include the word 'think' in what they said to you. Anyone who makes their living doing this work every day should not need to speculate on this job - they should 'know'.

As others have already said, there doesn't seem to be any need to need to drop the engine, and the TSB doesn't mention it either. However, how they choose to do the job is unfortunately out of your hands, and you'll just have to hope for the best. And you will of course need to check for leaks for some period of time after the job has been completed.
 
Yes, really bad news to need an engine repair as significant as this one will be. And I have to say that it's unsettling to have them include the word 'think' in what they said to you. Anyone who makes their living doing this work every day should not need to speculate on this job - they should 'know'.

As others have already said, there doesn't seem to be any need to need to drop the engine, and the TSB doesn't mention it either. However, how they choose to do the job is unfortunately out of your hands, and you'll just have to hope for the best. And you will of course need to check for leaks for some period of time after the job has been completed.
little bit offtopic,
Fully agree with you they have to be sure but my reality check in the past few years and not just the Auto area but also Home repairs, HVAC and even in the IT areas (which was surprise to me) shows that it is rare nowadays to find and hire really qualified experts.
Mediocre yes but quality is rare. Plus 90% of the people lie through their teeth without blink of an eye.
 
I was suprised about engine drop. The guy said they didnt think they had enough clearance to access everything. I sent them the TSB. Anyone in Central MA had this done? Which dealership did you go to?
Please keep us updated how the repair goes changes13. I just found a leak on my 2018 Sport today, I was hoping it was just the belt tensioner but upon closer inspection it looks identical to yours (pic attached). I'm taking mine to the dealer next week to see what they say but I don't have high hopes. I live in a pretty remote area with access to only 2 Mazda dealers (both owned by the same company) so I don't have a lot of options. Pretty nervous so I'd appreciate learning everything I can from your experience!

PXL_20210517_200434910.jpg
 
Forgot to update. The dealer used the TSB to fix the leak. They didn't have to drop the engine. Driven about 200 miles since, no sign of leak, but guessing it's too early to tell right now. So far so good though.
 
I just found a leak on my 2018 Sport today, I was hoping it was just the belt tensioner but upon closer inspection it looks identical to yours (pic attached).
There’s very thick and very minimum amount of oil inside of belt tensioner. The leak from tensioner usually will only be an oil film coated on the tensioner itself only. You won’t see any oil dripping to any other areas. Here’s what my leaky belt tensioner looks like on my 2016 CX-5 at 41,150 miles:

45581DFC-A798-401C-8B04-1A98995623CC.jpeg


Make sure to show the TSB to your Mazda dealer when you take your 2018 CX-5 Sport in for timing chain cover leak.
 
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