MG4 Reduction Gearbox Oil Leak

View attachment 12061
The oil that was leaking from ours was pretty clear and had a bit of a yellow colour, didn’t look at all discoloured or cloudy (well assuming wiping if off the bottom would show this)
That is the colour I would expect it to be.
Not a shade of milky beige or grey in colour
 
Had a conversation with my local dealer earlier today, who has told me the comms of how to fix the issue have finally come from MG (nothing new. changing the oil...). The director has been inform and apparently will be applying pressure on the servicing team to make sure they start the work asap. Will know more details next week.
 
Had a conversation with my local dealer earlier today, who has told me the comms of how to fix the issue have finally come from MG (nothing new. changing the oil...). The director has been inform and apparently will be applying pressure on the servicing team to make sure they start the work asap. Will know more details next week.
Changing the oil? Doesn't sound too promising...
 
I've been trying to communicate with my dealer (Unity Coventry) re my concerns around the oil leak. They promised a call back from the service manager which never happened, then called me to tell me I could have my money back on Monday if I decided to, after grumbling about the 600 miles I've done. I hesitated to tell them that consumer protection doesn't necessarily fit to their timescale and that the 30 day limit would still apply. Their response to my concerns was initially that they hadn't heard of any oil leak problems, and then they switched to saying that forums are full of nervous buyers who exaggerate stuff.

Needless to say, I have zero confidence in my dealer and they seem to be spivs who'll say anything to get a sale but then leave you to fend for yourself.
Don’t know how much you need your car but I’d reject it with that flyby-night bunch and if you can wait, and feel these issues will be sorted, order again through a dealer who does customer service.
 
Had a conversation with my local dealer earlier today, who has told me the comms of how to fix the issue have finally come from MG (nothing new. changing the oil...). The director has been inform and apparently will be applying pressure on the servicing team to make sure they start the work asap. Will know more details next week.
been there done that has not worked for most people, unless they are trying a different grade of oil !!!
 
Hope the breather replacement has worked for those who have had there's done as my car is still at the dealers
 
I’ve yet to see any official announcement about the issue. That being the case, I think there are still a lot of ‘opinions’ as to the problem and the fix. Hopefully MG will have something official out tomorrow…
Dead right Diggsy 100% nothing official.
I said the very same in #620 page 31 in this thread I very pleased to read you agree, I have pointed out once or twice before they MG, appear to be very good at Mushroom Management.
Les
 
Dead right Diggsy 100% nothing official.
I said the very same in #620 page 31 in this thread I very pleased to read you agree, I have pointed out once or twice before they MG, appear to be very good at Mushroom Management.
Les
Indeed. I’d imagine a lot of current and prospective owners alike are watching this very thread with interest.

Here’s hoping for a simple enough resolution. Would be a crying shame to see a car that is getting such glowing reviews have it all spoiled by this kind of issue.
 
I’ve yet to see any official announcement about the issue. That being the case, I think there are still a lot of ‘opinions’ as to the problem and the fix. Hopefully MG will have something official out tomorrow…
Agree, let's hope it's the same issue/fix for everyone. We definitely need confirmation from MG
 
Agree, let's hope it's the same issue/fix for everyone. We definitely need confirmation from MG
Do ICE gearboxes have breathers? I have changed oil in a gearbox before and usually just plugs. Gear boxes work on pickup and splash lubrication and when oil gets hot there is enough air void space for any expansion of oil. So why need a breather or open to atmosphere? So is the leak coming from a poor thread or seal on the top plug? Hopefully MG will sort but wish I could have a look at it myself.
 
Do ICE gearboxes have breathers? I have changed oil in a gearbox before and usually just plugs. Gear boxes work on pickup and splash lubrication and when oil gets hot there is enough air void space for any expansion of oil. So why need a breather or open to atmosphere? So is the leak coming from a poor thread or seal on the top plug? Hopefully MG will sort but wish I could have a look at it myself.
I think the answer is in the name and you have answered it yourself - the gearbox heats up and the oil expands so the air above the oil has to “breath” in and out to compensate otherwise pressure build up will help the oil to bypass seals or gaskets.
 
I used to have a Yamaha XJ900S back in the day - a shaft drive bike. The shaft drive assembly had a breather, and a "milky" solutions sometimes came out of the breather if you used the bike after it had been standing unused for a long time. (Moisture ingress mixing with the oil. Once you had the bike going to allow the oil to circulate and get up to temperature - so evaporating the moisture - all seemed to settle down).
 
If you think about it, breather design isn't straightforward - it has to block liquid flow in either direction, whilst permitting bidirectional air flow. It must help if there's plenty of space to work with - which is probably not the case with a rear-mounted electric drive...
 
I used to have a Yamaha XJ900S back in the day - a shaft drive bike. The shaft drive assembly had a breather, and a "milky" solutions sometimes came out of the breather if you used the bike after it had been standing unused for a long time. (Moisture ingress mixing with the oil. Once you had the bike going to allow the oil to circulate and get up to temperature - so evaporating the moisture - all seemed to settle down).
Back in the day I owned several British motorcycles and over the years they must have cost me a fortune in Hermatite sealing compound but then along came the Japs
No oil leaks 12 volt lights and brakes that worked wonderful.
Les
 
It looks like it probably needs a baffle plate under the breather as in that diagram the breather seems to be directly in line with the large reduction gear which is probably centrifugally flinging oil directly out of the breather.
 
It looks like it probably needs a baffle plate under the breather as in that diagram the breather seems to be directly in line with the large reduction gear which is probably centrifugally flinging oil directly out of the breather.
Yes. Now that would be a difficult retrofit, as I'd have thought that the motor/transaxle unit would have to be removed and stripped. A large headache for MG...
 

Are you enjoying your MG4?

  • Yes

    Votes: 535 79.1%
  • I'm in the middle

    Votes: 90 13.3%
  • No

    Votes: 51 7.5%
Support us by becoming a Premium Member

Latest MG EVs video

MG3 Hybrid+ & Cyberster Configurator News + hot topics from the MG EVs forums
Subscribe to our YouTube channel
Back
Top Bottom