[Rotary1]

Originally Posted by vanos84

I just had my surge tank replaced yesterday, picked up the car today, and they replaced it with a 17137889450 model. I hope it lasts but I'm not feeling too confident considering the amount of heat generated in the vicinity of the tank. Does anyone know where the point of failure is on these tanks? I would guess the seams?

I would think the seams, that is where it looked like my tank was leaking. The dealer said the tank was upgraded (I just had it replaced first week of Nov. and you can see pictures in this thread).

[M5Neededi]

Originally Posted by n33d4speed

Old part number was 17138090271. New part number is 17137889450.
Part still manufactured by same company with a technical update referring to the sensor. Does not look like an engineering change.

Hmm, looks like BMW or the expansion tank manufacturer has attempted to address the problem. This is a warning when I look up the old part number. And the new one says it replaces the old one. Looks promising to me.

[GranitM5]

I've contacted my dealer about mine. This past year, I got the message 3 times. I've also cleaned some residue around the coolant tank. Yesterday, I could smell it inside the car. Lets see how it goes!

[LORDLODOSS]

Any update? Trying to decide between an M5 or E63S and this is one of the main consideration's vs the RMS issue on E63S.

[Maverik259]

Originally Posted by LORDLODOSS

Any update? Trying to decide between an M5 or E63S and this is one of the main consideration's vs the RMS issue on E63S.

I would hardly call this a serious enough issue not to purchase. It's an extremely minor thing. All that really is happening is the presuure is building and the cap isn't secure enough so it spits. In a few small cases it has leaked bad enough to flow over into the driver side injectors/spark plugs. Doesn't help that there is a drainage cut out in the area around the cap that allows the fluid to literally flow inward toward the engine. That was pretty dumb.

Also doesn't happen to everyone.

[pbonsalb]

I’d rather change a coolant tank than a rear main seal. But I understand the Mercedes thing is probably due to crankcase breather valves, so it’s really a question of how hard it is to change those preventatively versus monitoring the BMW coolant tank. I am assuming the PCV valves are buried somewhere that makes inspecting them difficult. Maybe the aftermarket has improved valves like there are for the BMW N54 motor that I had in another car. No improved BMW coolant tank yet as far as I know though someone recently reported the part number changed (apparently the tank looks identical but maybe the plastic is better).

[AHall]

Originally Posted by LORDLODOSS

Any update? Trying to decide between an M5 or E63S and this is one of the main consideration's vs the RMS issue on E63S.

I originally considered the E63S but for me the M5 was a pretty obvious better choice. When I was trying to decide the reviews favored the M5. Then the was at least one owner hear that wrote a thorough comparison after he traded his E63 for an M5. I was/am unaware of the rear main seal issue. Are there reports of the seal failing? I have not had any coolant tank leaks in the almost two years of ownership, but I do monitor it often. I did not know they were even still making the E63S.

[LORDLODOSS]

Originally Posted by AHall

I originally considered the E63S but for me the M5 was a pretty obvious better choice. When I was trying to decide the reviews favored the M5. Then the was at least one owner hear that wrote a thorough comparison after he traded his E63 for an M5. I was/am unaware of the rear main seal issue. Are there reports of the seal failing? I have not had any coolant tank leaks in the almost two years of ownership, but I do monitor it often. I did not know they were even still making the E63S.

Here is the thread on the RMS issue.

https://mbworld.org/forums/w213-amg/...r-failure.html

Sounds like the expensive repair happens when the coolant gets to the injectors. Base on the pics provided here I would think you can build some kind of barrier to prevent leaks from dripping towards the engine.

[G-M5]

I replaced mine for $150 and had MT-12 coolant put in. Better to do it before it fails. I’m at 15k miles.

[TFBravo]

Originally Posted by AHall

I originally considered the E63S but for me the M5 was a pretty obvious better choice. When I was trying to decide the reviews favored the M5. Then the was at least one owner hear that wrote a thorough comparison after he traded his E63 for an M5. I was/am unaware of the rear main seal issue. Are there reports of the seal failing? I have not had any coolant tank leaks in the almost two years of ownership, but I do monitor it often. I did not know they were even still making the E63S.

That might have been me, I've traded in a 2020 E63S for a 22 M5C last year, I've written a pretty good comparison. They should be back to selling 2023 E63S after 2022 hiatus in the US, in Europe 2022 MY still sold. I would suspect the wait for an E63S is probably longer than M5 and have no idea if there will be a 2024, meaning as we're in May the 2023s might be done.

[TFBravo]

Originally Posted by ResIpsaLoquitur

This happened to so many members. I'd be furious to replace them, only to have the same exact issue. Despite a lot of advice on here, I never went with aftermarket pads for my pre-LCI, and I am very satisfied with the reduction of noise on my LCI so far at just about 4k on the clock. I was squealing in my previous M5 by high hundreds of miles.

Mine is a 2022 and started the noise around 4.5kish, its sitting at 5.6k miles right now so maybe it was at 5k. Not as bad to be honest as it was on my E63S.

[grimluster]

Is the expansion tank still an issue on the 2023's?

[Maverik259]

lol how did a leaking coolant tank turn into a brake pad thread? hahaha

its a performance "feature" according to BMW...

[PetroM5]

Just got a low engine coolant warning this weekend. Checked the tank for any leaks but nothing was visible. I had to add about 16 ounces of coolant. I just got the car 3 weeks ago pre-owned. A 2022 M5C with 11 thousand miles. If it happens again, it will be going to the dealer for a pressure test and inspection.

[Tiz113]

Checked under the hood a couple weeks ago and saw this white residue on the coolant reservoir and thought, huh that's not normal. Never got a light for low coolant or anything like that though.

Brought it to BMW and they found a pinhole leak. Covered under warranty thankfully.

Link to video of the tech that serviced.

https://youtube.com/shorts/FFs6PJZGmwE?feature=share

[sys999]

Originally Posted by Tiz113

Checked under the hood a couple weeks ago and saw this white residue on the coolant reservoir and thought, huh that's not normal. Never got a light for low coolant or anything like that though.

Brought it to BMW and they found a pinhole leak. Covered under warranty thankfully.

Link to video of the tech that serviced.

https://youtube.com/shorts/FFs6PJZGmwE?feature=share

::Exact:: same spot on reservoir where mine occurred… after they supposedly pressure tested post recent fluid flush. Thank you BMW ❤️.

New tank inbound tomorrow, will be replacing this weekend.

[pmsteinm]

Here is the SIB on this issue for those that aren't aware:

SIB 17 02 22
LEAKING COOLANT EXPANSION TANK (S63)
2022-09-22
This Service Information Bulletin (Revision 1) replaces SI B17 02 22 dated June 2022.



What’s New (Specific text highlighted):

Part number for the expansion tank changed


MODEL

E-Series

Model Description

Production Date

Affected Option Code

F90 (M5 Sedan)

F91 (M8 Convertible)

F92 (M8 Coupe)

F93 (M8 Gran Coupe)

F95 (X5 M Sports Activity Vehicle)

F96 (X6 M Sports Activity Coupe)





SITUATION

Coolant is leaking from under the car which is equipped with the S63 engine. A low coolant warning might also be displayed (CC Message ID166).



CAUSE

Chemical/thermal reaction with the plastic material of the expansion tank and coolant.



CORRECTION

Drain all the coolant from the engine, replace the expansion tank; and fill with new coolant.



PROCEDURE

Drain the coolant: Follow Repair Instruction 17 00 008 Draining and topping up coolant for high-temperature circuit
Replace the expansion tank: Follow Repair Instruction 17 11 100 Removing and installing/replacing coolant expansion tank
Fill and vent the cooling system


NOTE: There are specific instructions for the expansion tank replacement based on model. These instructions must be followed to ensure that coolant does not leak onto the fuel injectors during replacement of the expansion tank.



PARTS INFORMATION

Obtain and confirm the part numbers for your specific vehicle by entering the chassis number in either ETK or AIR which takes into account specific equipment and/or options.



Part Number

Description

Quantity

17 13 7 889 450

Expansion tank (M5, M8)

1

Or:





17 13 8 689 765

Expansion tank (X5 M, X6 M)

1



Additionally, other materials and small parts that are not specified above, such as fluids, lubricants, one-time use screws, nuts, and seals, which must be replaced or installed according to the ISTA repair instructions/ETK, must be selected from the Electronic Parts Catalog, or other approved BMW resources, according to the respective vehicle type. Invoiced these items separately under the Recall repair Defect Code listed in this bulletin.

[sys999]

Just did it this morning, easy fix. My old tank was hairline cracked up top and had a very large crack on underside near lip. Dried coolant everywhere in engine bay but it missed the injectors so that’s good. Hope the new part number does the trick. If you smell coolant just replace the tank.

[M5Neededi]

Big relief it dd not damage the injectors. I hope the new tank is built better and will last longer. Was this the first time you had this issue?

Originally Posted by sys999

Just did it this morning, easy fix. My old tank was hairline cracked up top and had a very large crack on underside near lip. Dried coolant everywhere in engine bay but it missed the injectors so that’s good. Hope the new part number does the trick. If you smell coolant just replace the tank.

[sys999]

Originally Posted by M5Neededi

Big relief it dd not damage the injectors. I hope the new tank is built better and will last longer. Was this the first time you had this issue?

Yes, 2018 M5 and first time at 43k.

[sys999]

I should also add that I think the straw that broke the camels back was “preventative maintenance” at the dealer. I just had a coolant flush and I assume the pressure test at the end put the nail in the coffin because I had no issues prior. As soon as I brought it home I smelled coolant and thought the high schooler who did the work spilled the stuff everywhere. Guess the high schooler instead grenaded the tank and didn’t care to look/listen for hissing.

[M5Neededi]

That is unfortunate. Real preventative maintenance would have replaced the tank which is known to crack.

At 43k you had a far better run than the original tank on my M5 @ 22k miles.

At times I swear I can smell coolant. But I do not see any signs when I look under the hood.

Originally Posted by sys999

I should also add that I think the straw that broke the camels back was “preventative maintenance” at the dealer. I just had a coolant flush and I assume the pressure test at the end put the nail in the coffin because I had no issues prior. As soon as I brought it home I smelled coolant and thought the high schooler who did the work spilled the stuff everywhere. Guess the high schooler instead grenaded the tank and didn’t care to look/listen for hissing.