MG4 Reduction Gearbox Oil Leak

My August built, November delivery Trophy now has 21k miles on it now & I've got a couple of weeks off so I'm looking at replacing the diff oil myself.

Mainly I'm curious as to how much oil is in there exactly so I'll be draining & measuring it & also just for some preventative maintenance because of the milage I do.

It did have the oil leak within around 40 miles & a day of delivery, I was very lucky and was one of the first to get the breather fitted in early November the following day & touch wood I've not noticed anything since however I've always been suspect of how much oil is actually in there.

Just confirming if poss as I'm 99% sure but for people in the know it's the same oil as used by the MG5 by the looks of Brown & Gammons website, Sl2808 Shell E6? As I don't really want to shout about me doing this to any dealers for obvious reasons 😁.

Sorry I've followed this thread on & off but have missed quite a bit, is there a new revised version of the original replacement breather that I would have had fitted in November. I have read a few things that have hinted towards this but just haven't got the time to go through all the pages unfortunately so apologies for being lazy but anyone that knows if it has been improved or changed I'd be very grateful?.

& finally if Macdoodle (I believe but apologies if I've got the name wrong) who's done the job has any pointers I'd also be very grateful, I'm not a mechanic by any means but have done quite a bit of maintenance over the years, dsg services etc. so I have no doubts about doing it but is there any crush washers on drain bolts etc. That should be replaced, I wouldn't have thought so but thought I'd ask the question. Would have preferred to follow a workshop manual but any official info seems very difficult to get hold of still!.

Sorry for the essay guys & appreciate any help! 😁
 
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My August built, November delivery Trophy now has 21k miles on it now & I've got a couple of weeks off so I'm looking at replacing the diff oil myself.

Mainly I'm curious as to how much oil is in there exactly so I'll be draining & measuring it & also just for some preventative maintenance because of the milage I do.

It did have the oil leak within around 40 miles & a day of delivery, I was very lucky and was one of the first to get the breather fitted in early November the following day & touch wood I've not noticed anything since however I've always been suspect of how much oil is actually in there.

Just confirming if poss as I'm 99% sure but for people in the know it's the same oil as used by the MG5 by the looks of Brown & Gammons website, Sl2808 Shell E6? As I don't really want to shout about me doing this to any dealers for obvious reasons 😁.

Sorry I've followed this thread on & off but have missed quite a bit, is there a new revised version of the original replacement breather that I would have had fitted in November. I have read a few things that have hinted towards this but just haven't got the time to go through all the pages unfortunately so apologies for being lazy but anyone that knows if it has been improved or changed I'd be very grateful?.

& finally if Macdoodle (I believe but apologies if I've got the name wrong) who's done the job has any pointers I'd also be very grateful, I'm not a mechanic by any means but have done quite a bit of maintenance over the years, dsg services etc. so I have no doubts about doing it but is there any crush washers on drain bolts etc. That should be replaced, I wouldn't have thought so but thought I'd ask the question. Would have preferred to follow a workshop manual but any official info seems very difficult to get hold of still!.

Sorry for the essay guys & appreciate any help! 😁

Good lord, 21k in 4 months, that's some going. Yes please do change your oil if you get a chance Spence, be really interested in the quantity and condition.
As for tips, really quite straightforward. I just reversed up on ramps, popped the wavy tray off and undid the drain with an adjustable wrench - it's a square headed plug.

I only got 600ml out after just a few weeks on the road, there will be a little oil left in there as residue I guess but I doubt there's much.
The fill is above the N/S driveshaft, 17mm hex if I recall correctly, I just reused the washers, seems fine.
For filling, I used a long bit of clear tubing with a funnel pushed in one end. opened the charge port door and supported the funnel with that and ran the pipe above the rear tyre and down into the box's fill hole. Downhill all the way with that route so it filled pretty willingly.

I'm still running with a full synth ATF that was left over from my Nissan leaf days, might get the 'proper' stuff in there sometime now it's finally stopped dumping it on the road.
My fill hole is now my breathe hole of course but it doesn't really cause any inconvenience .
 
As mentioned, it’s at the back of the manual (page 321)…

Electric drive transmission fluid
Shell E-Fluids E6 iX (SL2808)
L 0.9
Does anyone know where you can purchase this correct oil from please.

And Spence7788 if you do drop the oil could you please post a picture of the old stuff as well as how much came out thank you, and yeh I agree some mileage your doing for sure.
Les
 
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Got my car back today ... items carried out today listed below.

View attachment 16425

I took a photo of the new breather - this is what it looks like (with the adapter removed and also partially inserted - looks like a push fit arrangement):

View attachment 16426View attachment 16427
This breather looks identical to the original modified breather from November. The only difference could be no internal ball valve inside the actual breather part at the top which would make sense as any pressure build up could cause a spitting action. This is of course just my guess, other than that it looks the same.
 
Thanks for the oil info guys, I remember reading that a while ago in the manual actually now I come to think of it so that's definitely the right stuff to use, was just double checking.

Yeah it's used as a taxi just doing a long school run so x2 130 mile stints a day 5 days a week which it's been brill so far for hence the milage racking up & me not wanting to wait weeks / months & probably a big fight with MG to replace a reduction gearbox so it's just for peace of mind really! I did it on my previous Leafs too which was well worth doing.

It's probably 70% A1 & the rest country roads & is driven hard on occasion (usually on the way back 😁) so although I'm pretty mechanically sympathetic alot of that 21k has been at motorway speeds (although a lot is single carriageway up here in the north so nothing too silly). But it's definitely not been babied around town so if oil was going to escape my use is a pretty good test to see how much is left in there!.

Thanks very much Macadoodle for the info, really appreciate it & it sounds straightforward enough, I'll be sure to take plenty of pics of the old oil & an accurate measurement. Did you put the full 900ml back in each time you've tested yours? which looks brilliant btw & might look at doing something similar if you don't mind me stealing your design.

I've searched quite a lot for it online Les & I'm pretty sure the only place selling it online is Brown & Gammons but it's nearly £20 delivery as I was about to order it last night So just under £50 delivered for 1l, might just be my northern tightness but I think I may just pop into a different dealer and pickup or order one and save the £20! 😁.

Thanks for all the help guys. 👍
 

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Thanks for the oil info guys, I remember reading that a while ago in the manual actually now I come to think of it so that's definitely the right stuff to use, was just double checking.

Yeah it's used as a taxi just doing a long school run so x2 130 mile stints a day 5 days a week which it's been brill so far for hence the milage racking up & me not wanting to wait weeks / months & probably a big fight with MG to replace a reduction gearbox so it's just for peace of mind really! I did it on my previous Leafs too which was well worth doing.

It's probably 70% A1 & the rest country roads & is driven hard on occasion (usually on the way back 😁) so although I'm pretty mechanically sympathetic alot of that 21k has been at motorway speeds (although a lot is single carriageway up here in the north so nothing too silly). But it's definitely not been babied around town so if oil was going to escape my use is a pretty good test to see how much is left in there!.

Thanks very much Macadoodle for the info, really appreciate it & it sounds straightforward enough, I'll be sure to take plenty of pics of the old oil & an accurate measurement. Did you put the full 900ml back in each time you've tested yours? which looks brilliant btw & might look at doing something similar if you don't mind me stealing your design.

I've searched quite a lot for it online Les & I'm pretty sure the only place selling it online is Brown & Gammons but it's nearly £20 delivery as I was about to order it last night So just under £50 delivered for 1l, might just be my northern tightness but I think I may just pop into a different dealer and pickup or order one and save the £20! 😁.

Thanks for all the help guys. 👍
Hi again spence, I’m with you £20 delivery ridiculous but if it’s the only way, unless someone on here can help out who might live nearby to Brown & Gammons and could pop in and send it to you far cheaper come on forum member in that locality help a fellow member out can’t you.

So spence getting back to the car, if I might go of track a little 21000 miles in what 5 months some going, but out of interest how is the rest of the car holding up plus and how are the Tyres doing, I’m assuming of course you have still got the same tyres that came on the car as new, I’m sure there’s a few here as well as me would like to know so if you don’t how is the car holding up.
Les
 
Does anyone know where you can purchase this correct oil from please.

And Spence7788 if you do drop the oil could you please post a picture of the old stuff as well as how much came out thank you, and yeh I agree some mileage your doing for sure.
Les
B&G stock the correct oil.

edit: didn’t see that others have already posted this. My bad!
 
Yeah, that's very kind but wouldn't want anyone going out of their way for that, I'll just pick one up locally but cheers 😃.

No worries at all, I've been pretty impressed with the build quality overall tbh, better than my mk2 Leaf & I've had less issues with this than the MG5 I had previously although that was nothing major, just a wind seal & AC gas leak in 42k in that but I didn't have it long really. the leaf in 80k had a few niggly things done under warranty, nice car & a good introduction to EV's but why anyone would buy one now over an MG4 now I wouldn't know, the Mrs works for Nissan & there still selling surprisingly well!

I've had a few software & module updates but from delivery nothing was terrible imo bar the LKA, I think mine was one of the second batch that didn't have the driver alert sensor thing, updates have improved the infotainment slightly but I haven't noticed anything really & my android auto etc. Has been very reliable.

The only thing that concerns me re reliability is this reduction gearbox oil issue tbh. I'll probably keep it until 2 years or 120k ish all going well so I'll be well out of warranty by then (that's only 60k for taxis).

Re tyres I actually put Michelin CrossClimate 2's on at 6k as the girl I pickup is on a remote farm in the Scottish borders & even the A1 can be quite sketchy up there, it was actually completely white one day and wagons pulling over etc., the only day I've turned around and went home that made my decision to change 😁.they've soldiered on through some really deep snow where i wouldn't have stood a chance on the OEM tyres, I didn't find the Conty's terrible but even in the warmer weather recently I've really been so impressed with these Michelin's are soo much better I wouldn't use anything else now.

Anything else just fire away. 😃
 
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Hi again Spence thank you for the posting above I have just been tell my wife about your mileage as she owns a 4 it the SESR and she loves it now she has got the hang of it got it, October 22 she got it and it’s now done 2200 miles there about and I showed her the pictures you put here earlier and she said about your car 🤔it needs a wash 😦lol, but thanks for the info about your tyres also
Les
 
Good to know nothing major has gone wrong in 21k, that'll be the 2 year mark for me !
I refilled with 850ml every time Spence. When the car has its rear on a standard set of ramps it does leave around 20ml in the bottom of the box, plus whatever residue is clinging to the internals I guess, was wary of overfilling.
Yep, feel free to pinch my side breather idea, can't be arsed patenting it 😊 I received the brass elbow from china I was waiting for so I'll probably post a pic of the improved set up I'm planning to fit.
My leaf is an ex taxi from Dundee, bought it cheap with just over 100k at 3 yrs old. Actual chunks came out with the gear oil when I changed it 😧 but it Still ran smooth and quiet for another 25k until we just SORN'd it after wifie had had enough of the short range.
 
Haha Les, she's not wrong! 🤣. it's generally like that most of the time ATM, plates and cameras, maybe a window quickly wiped each day but it's a losing battle ATM keeping it clean!

Every so often I'll give it a good going over, I use to quite like my detailing believe it or not 🤣, I've recently started using Bilt Hamber Touchless which is honestly brilliant at getting the thick off, spray it on with a garden sprayer, leave for a few mins and hose/jet wash off, it's amazing stuff and pretty safe unlike a lot of TFR's.

Haha, appreciate that Macadoodle, I'll do the change initially with the "correct" level and see how I get on, I'm expecting it to leak again, at least a little anyway!

Yeah I was wondering if I should get it completely level or not like I use to for the dsg service but it was a bit of a pita because my ramps I've got are quite high & I've never properly looked at where to jack the MG yet so I'll probably stick to what you've done, can't really see it going wrong leaving it to drain as much as poss and putting around 850ml back in 👍, out of curiosity before I get a chance to look is there the usual fill level hole where it'll start to come drain back out if the cars level etc. to set the diff at the correct level.

Yeah there's a few with high milage on now, mine was a 40kw and had a recall done for the reduction gearbox so it was done then, then I did it around 30k later and I was surprised how filthy it was! Mind like you say they seem to keep going generally!

Cheers
 
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Well the day has come to say reject oil leak again after the new breather fix 3rd time now anybody else had this issue after there original fix
Really poor, it's amateur hour stuff from MG!

Macadoodle give them a ring and offer to sell them the rights to your fix
 
Really poor, it's amateur hour stuff from MG!

Macadoodle give them a ring and offer to sell them the rights to your fix
I have now sent the rejection email back to finance company let’s see what happens but it’s worse now than before the fix. This will be the 7th time car as been in garage in 5 months over 3 months in garage let’s see how the rejection goes
 
I have now sent the rejection email back to finance company let’s see what happens but it’s worse now than before the fix. This will be the 7th time car as been in garage in 5 months over 3 months in garage let’s see how the rejection goes
5 months of ownership, over 3 months in the garage. There is no way that could be seen as acceptable by anybody, hopefully your rejection goes through smoothly
 
5 months of ownership, over 3 months in the garage. There is no way that could be seen as acceptable by anybody, hopefully your rejection goes through smoothly
Last time was they had to be given the chance to fix if it happened again rejection now it’s happened again the drive is covered in oil and under tray is drenched in oil.worse than it was with the original part
 
Last time was they had to be given the chance to fix if it happened again rejection now it’s happened again the drive is covered in oil and under tray is drenched in oil.worse than it was with the original
It's quite the skill to take a car in to fix a problem and to give you it back having made it worse. Hats of to the dealer and MG
 

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