[slowblackx3f25]

Hi All,

Has anyone experienced rear diff leaks on the 2017 x3's?

I noticed oil sweat on the diff when it was on the hoist, has anyone noticed the same and got it fixed or left it as is? if you did get it fixed, how much did it cost you?

If I leave this as is (diff transmission oil sweat/minor leak) what will happen?
I believe there might be a chance of reduced performance?

I will get it checked out by a BMW experienced automotive tech in Ontario, Canada just to be on the safe side, when I go in for my next oil change.

Has anyone experienced rear diff leaks on the 2017 x3's?

Just curious to see if anyone else has been through this issue... and FYI: my x3 is out of warranty, so I'm forced to get an independent BMW repair shop to have a look.

Any sort of input is appreciated.

Thank you!!!

[pungo]

A diff leak at 3 years is not common, but it can happen. Without knowing how much has leaked out, you should a least check the level. It doesn't hold much fluid and if you run it too low, you could ruin it. There's several places it can leak from, but you didn't say which seal is leaking.

[slowblackx3f25]

Yes, 3 year-old bmw with a diff leak doesn't add up. I'm not sure which seal it is, I will get it checked out during my upcoming service. I will get it fixed, any sort of leaks is basically liquid money leaking, and is not a good thing long term or short term. I will get it fixed and fluid topped up.

Thank you Pungo!

If anyone else had this issue and got it fixed, let me know how much it cost.

[Bdavi011]

Check your engine bay, make sure there isn't anything else leaking. Such as the oil filter housing. Tiny chance oil leaking from there could make it towards the back part of the car during highway speeds. Very unlikely but wouldn't hurt to check nothing else is leaking.

I would try take it to a mechanic sooner than later. Itd be pretty pricey to replace a differential if it runs dry.

[383vett]

I would get under it and clean it with shop towels and Brakeleen. This will make it easier for you or your mechanic to diagnose the leak.

[slowblackx3f25]

I got it fixed today morning at RMP Motors here in Ontario, Canada.
The diff was leaking. The diff seals were replaced. I didn't take chances and had both seals replaced
(left and right)

Now I will monitor for the next few weeks. Drives noticeably better. No jerks under heavy throttle. Transmission feels a-lot more smoother than before.

If you have this issue, or any sort of diff issues, bring it to a shop/individual who has numbers of experience working on BMW's***** and that will do this job with skill, expertise, effort and interest. Don't let anyone else touch your BMW's unless it's an experienced tech that knows BMW's well!

Thanks everyone for inputing your feedback! Highly appreciated as always!

[pungo]

Originally Posted by slowblackx3f25

I got it fixed today morning at RMP Motors here in Ontario, Canada.
The diff was leaking. The diff seals were replaced. I didn't take chances and had both seals replaced
(left and right)

Now I will monitor for the next few weeks. Drives noticeably better. No jerks under heavy throttle. Transmission feels a-lot more smoother than before.

If you have this issue, or any sort of diff issues, bring it to a shop/individual who has numbers of experience working on BMW's***** and that will do this job with skill, expertise, effort and interest. Don't let anyone else touch your BMW's unless it's an experienced tech that knows BMW's well!

Thanks everyone for inputing your feedback! Highly appreciated as always!

If you had jerking under heavy throttle prior to having it filling with fluid and it now drives noticeably better, your fluid was really low and you were causing damage to the internals, how much, who knows. Since the diff does not have a drain plug to drain all the fluid out, there may be metal dust still insides the diff. I would have the fluid changed again after a few hundred miles and see if any metal dust comes out in the fluid.

Good you got it repaired before the rear locked up

BTW, a competent mechanic can replace those outdrive seals, there's nothing special only to BMW. They didn't disassemble the diff, right?

[slowblackx3f25]

pungo Yes, it would jerk from a full stop at a red light or stop sign, but it was very minor but I noticed it, and so did my father, and he wanted to drain and refill the diff gear fluid, but it was leaking so we never did anything about it, and left it as is.

It actually started to jerk a lot more as months went by, and that's when I decided to get the diff leak fixed, even though it was very minor leak (it was a oil-sweat type of leak), but a leak is a leak, and any sort of fluid leaking from anywhere is money leaking.

So we got it fixed at a very fair price. Our general mechanic quoted us $2,000.00 for the diff leak fix, and that's why we put it off, but when the jerking got worse, I did some research and found a BMW specialist to have a look and fix it, instead of the general mechanic that quoted us 2k.... which didn't seem reasonable to my dad and I...

I found RMP Motors on the e90-Post forums, and heard really good things about RMP Motors located in Etobicoke, Ontario, Canada. These guys really saved us A LOT of money... They work on BMW's only and they know BMW's really really well.

You are right, a competent mechanic can do it easily, but I wasn't going to take chances, and I rather bring my x3 to a BMW experienced mechanic from now on. Just for peace of mind.

The guys at RMP got it done really quick and at a reasonable price. They didn't fully disassemble the diff. They did it the smart way, not the hard way. (work smart, not hard).

The general mechanic of mine did not mention the diff will lock up if I leave it leaking... he just said it'll start making noises.... If I knew it would lock up and cause damage internally, I would've got this fixed months ago... this goes to show that I should've done my OWN research and not go based off someone else's knowledge -__-

Also, my dad and I purchased this x3 in question from a third-party private dealership, and we never did our own inspection (put it on a hoist, and inspect underneath, under the hood), so it was a blind-vehicle-purchase which resulted in all this mess... so I believe we purchased this x3 2017 with a diff leak...

I would recommend everyone to do their own inspection, even if you buy CPO/ or at a private dealership. Use your eyes, use your own brain, to view, to be aware of what you are buying.

After all, the vehicles we purchase represents us as who we are.
Well I should say the choices we make in life, makes us who we are today.

It's been day 2 since I fixed the leaking diff, and it drives so much better.
The x3 takes off smoothly and quickly... day and night difference.
The RPM needle moves better, I don't know how to explain that... like it shifts better now (automatically)

I will make sure I drain the fluid after a few hundred miles, and re-fill again.
I don't think I caused any damage... I hope not...

Sorry for the huge rant, but BMW's are worth every single 100$ bills lol... it's a different experience, and I can't wait to buy a M car, and I'll make sure it's CPO and purchased at the BMW dealership AND I do my OWN visual/physical inspection on the hoist before signing off on the vehicle purchase documents!!!

IF any of you live in Ontario, Canada and need out-of-warranty repair done on your BMW or BMW M, bring it to RMP Motors (Rocco and Johnny), they will take care of you.

But yes, I am super happy I got it fixed, and drives much, much better!!! Thanks again for all your feedback. I hope this helps someone else.

[Loc123]

I have a differential seal leak that the dealer told me today while getting my oil changed. He did not say it had to be done but let me know it was leaking. Not dripping just seeping. I did not ask for a price yet. But is bothering me already knowing it’s leaking.

[383vett]

Originally Posted by slowblackx3f25

pungo Yes, it would jerk from a full stop at a red light or stop sign, but it was very minor but I noticed it, and so did my father.
It's been day 2 since I fixed the leaking diff, and it drives so much better.
The x3 takes off smoothly and quickly... day and night difference.
The RPM needle moves better, I don't know how to explain that... like it shifts better now (automatically)

.

Normally if a differential was low on fluid, it would cause the gears to whine, then howl as the gears and bearings wear and finally, it might lock up. I'm not sure why your car drives better and faster and the tach "moves better" after the repair, but I'm glad your car is fixed.

[slowblackx3f25]

Originally Posted by Loc123

I have a differential seal leak that the dealer told me today while getting my oil changed. He did not say it had to be done but let me know it was leaking. Not dripping just seeping. I did not ask for a price yet. But is bothering me already knowing it’s leaking.

You should get it fixed to avoid any sort of damage. The diff on my x3 wasn't leaking... it was seeping but it got worse over time and I decided to get it fix (replaced rear diff seals left and right side)

It's a lot cheaper to get done than replacing the entire diff because it locks up without oil (even though it's not much of a huge leak) I had that problem too, knowing that there's a diff leak (seeping) bothered me so much so I ended up getting it fixed (non-warranty repair at an independent BMW shop)

I went almost a year without replacing the diff seals, but I noticed transmission jerks from a standstill take off, and that's when I decided to replace seals and drain and refill diff oil.

(take care of your car(s) and it will take care of you.)

[383vett]

Another thought is that if the differential is weeping and not dripping, it is really easy to check the oil level and top off if necessary. Brakekleen the differential so you can monitor how much it is really leaking and you will be good to go.

[Loc123]

Originally Posted by slowblackx3f25

You should get it fixed to avoid any sort of damage. The diff on my x3 wasn't leaking... it was seeping but it got worse over time and I decided to get it fix (replaced rear diff seals left and right side)

It's a lot cheaper to get done than replacing the entire diff because it locks up without oil (even though it's not much of a huge leak) I had that problem too, knowing that there's a diff leak (seeping) bothered me so much so I ended up getting it fixed (non-warranty repair at an independent BMW shop)

I went almost a year without replacing the diff seals, but I noticed transmission jerks from a standstill take off, and that's when I decided to replace seals and drain and refill diff oil.

(take care of your car(s) and it will take care of you.)

What kind of cost to fix? Dealer? Indy?

[slowblackx3f25]

Originally Posted by Loc123

What kind of cost to fix? Dealer? Indy?

Parts (the seals, transmission oil re-fill) + labour = $500CAD (USD:$395)
At an independent BMW specialist shop (I know the owner, he worked at the BMW dealership for 10+ years before opening up his own shop)

I wouldn't bring my x3 to the dealer as they will charge A LOT more, and my x3 isn't under-warranty... so it's not financially smart.

We don't have Indy's up here in Canada, we have MIDAS and other shops like Indy.

TLDR; paid 500$CAD (USD$395) for x3 rear diff leak fix, No dealer, no Indy's, went to an independent BMW/Euro specialized shop for this repair, saved A LOT of money... AND my x3 drives better

[Loc123]

Got two Indy prices. $400 and $525. The $525 place says they can do an aftermarket seal vs BMW seal for $425 but do not recommend it.

[Loc123]

? Should I be looking to change the front diff fluid at 63,000 miles?

[pungo]

Originally Posted by Loc123

? Should I be looking to change the front diff fluid at 63,000 miles?

I changed the front/rear diffs/transfer case/trans fluids at around that miles. Front diff and transfer case fluid was dirty, rear diff was clean. I recommend changing all.

[slowblackx3f25]

My x3 is at 70k miles, I didn't change the front diff fluid yet, only the rear.
I'm going to get it done soon.

I heard the trans fluid is lifetime... I got quoted 670$ to change trans/front and rear diff/transfer fluids... anyone else think this is way too much?

Another shop (another fixes-BMW-only-shop) quotes me 200$ to change front+rear diff/transfer case fluids...
This guy at this shop recommends I don't change the trans fluid... as it's 'BMW lifetime'

Why the huge price difference? Is it suppose to be this expensive for fluid changes?

Loc123 go with BMW seals... it's better. I wouldn't mind going aftermarket on the fluids...

[Wgosma]

Change the transmission fluid- highly recommend you use ZF Lifeguard fluid, yes the fluid itself is expensive.

Independent shop did my cars tranny for $590, did transfer case fluid for $125 and reset adaptations- This is smart preventative maintenance at mileage your car is currently at, ZF recommends fluid change at about 60K or so miles.

Do transfer case fluid, that made difference in how my car operated at very low speed, prior to fluid change car would 'crab' slightly pulling into garage- fluid change eliminated that and car is completely smooth

Prices you were quoted look reasonable.

[Bdavi011]

+1 on replacing Trans fluid. ZF (transmission manufacturer) recommends 60k miles service intervals. I would only use ZF fluid too. I know its expensive but why put anything else other than what was filled from factory?

[slowblackx3f25]

Thanks for your feedback! I will change the transmission fluid.

I got the transfer case/front+rear diff fluid changed today. It drives better (smoother). It definitely is better during slow speeds, it shifts very, very smooth (better than before the fluid changes).
I also got an oil change done as well. The rear diff fluid was clean... (oil wasn't dirty), so the diff internals are in good shape, nothing else came out with the oil, just clean oil.
I'm not surprised as I got the diff seals replaced not too long ago and the shop that did the seals added new diff oil, reason for the oil being clean and not dirty.

The transfer case fluid, front + rear diff fluid, + oil change ran me up 230$CAD (USD$180)

The BMW shop I brought my x3 recommends I DON'T change the trans oil, and that it's lifetime... I find it hard to believe, and I will replace the trans fluid soon... nothing's really lifetime on this planet...

I'll find the ZF fluid you guys mentioned and use this fluid. Thank you all for your feedback! I highly appreciate your time and support. Drive safe. Be well.

[slowblackx3f25]

So I got the transmission fluid drained and re-filled earlier last week, and it is night and day difference! It drives really smooth, and the power output is there at the wheels.

I can't believe BMW Toronto dealership said it doesn't need to be replaced and the fluid is good to last throughout the life of my BMW... WRONG! Fluids must be replaced at intervals recommended by the fluid's MFG...

My BMW x3 drives 10x better!

I am now up-to-date on my transmission fluids (front+rear diff, transfer case and tranny oil).

I use this chart to keep track:

——————————
TRANSMISSION:
——————————

Trans fluid:
Changed at RMP
@ 117,000KM
Rocco and Johnny
03/22/2021

Transfer case fluid:
changed at BMWIZARD
@ 113,712KM
02/06/2021

Front differential fluid:
changed at BMWIZARD
@ 113,712KM
02/06/2021

Rear differential fluid:
changed at BMWIZARD
@ 113,712KM
02/06/2021

I would recommend to do all four (trans, transfer-case , front, and rear diffs) oil drain and refill's all at once, if your pockets allow you to do so. It's highly worth doing so... these cars are ultimate driving machines and if you keep the lubricants fresh and up-to-date, they drive like-brand-new!!! I hope this helps someone! Take care! Drive safe, and stay healthy!!!