MG4 Undertray dip/bulge

[colsky]

In my opinion, what’s the point of having aerodynamic components, e.g the aero wheel covers, and the flaps on the Trophy, when there’s a massive gap under the car screwing up the airflow? It’s probably minimal impact, but the wheel covers aren’t going to be making much of a difference either are they?

If there are cars where it is properly attached, those can’t be “wrong”, and everyone else’s correct surely?

Agreed. What we need is a poll thread for MG4 owners - have undertray bulge/don't have undertray bulge. Reading through the forum I get the impression that there's more with the bulge than not. But, I did notice someone on here who picked up their Orange Trophy (the same model as mine) in the last couple of weeks, whose car I think was on the same boat as mine and whose VIN number was very close to my number (so probably from the same manufactured batch), whose car photos showed no bulge. Insert very confused emoji, or a Toyah emoji for "it's a mystery"!

 

[Ian Key]

It could be how they are fitted. Perhaps some are fitted from the outside in and others are from the centre out.

 

[colsky]

It could be how they are fitted. Perhaps some are fitted from the outside in and others are from the centre out.

And the ones with the oil leak are in, out and shaken all about!

Forgive me if this is a stupid question - does the undertray have to be taken off in order to fit the new breather?

 

[AndyL61]

And the ones with the oil leak are in, out and shaken all about!

Forgive me if this is a stupid question - does the undertray have to be taken off in order to fit the new breather?

I would say yes you would have to remove the tray to fit the breather. I couldn't see anyone tying to struggle through small gaps when you could take off the tray and have easy access.

 

[colsky]

I would say yes you would have to remove the tray to fit the breather. I couldn't see anyone tying to struggle through small gaps when you could take off the tray and have easy access.

So that throws another option into the mix - the cars arrive without the bulge (hence why MG aren't aware), the dealer takes the undertray off to fit the breather and puts the undertray back on incorrectly?

 

[siteguru]

Given that there are photos on this board (Oil Leak thread?) showing bulges on cars that have leaked without any work being done by dealers, I think that's a misdirection that won't help.

 

[colsky]

Given that there are photos on this board (Oil Leak thread?) showing bulges on cars that have leaked without any work being done by dealers, I think that's a misdirection that won't help.

Sorry, I'm overthinking this!

 

[Deleted member 9909]

So far

I contacted MG about the dip in the undertray that others also seem to have (noticed in oil leak thread). They say it’s not normal and would be replaced if approached by dealers. (well before breather fix)

Had an update from MG (after a small chase) Apparently a communication has been sent out to dealers this morning, asking any cases to be reported so they can get an idea of numbers etc.

There has been no formal communication released to the dealership network regarding the MG4 undertray to date, please accept my apologies for any confusion from previous correspondence.

There will be a communication released to the dealership network in the future regarding this but we cannot put a time scale on when this will be published.
This is because MG will be testing a modified undertray from SAIC.

At this stage, there has been no guarantee from seniors at MG Motor UK that undertrays will be replaced with a modified one as we are still at premature stages.

I would recommend keeping in touch with your dealership who can provide you with a finalised update once a communication has been published to them.

I’ve just come off the phone from my dealer who have assured me that all models they sent out have the same under-tray issue & it’s completely “normal” and the advice from MG is that the car is still fine to drive

A replacement under tray has been ordered, and ‘should’ be here next week?

Can you possibly share a screenshot of that email, my dealer said that MG told them the undertray is “by design”.

We've checked your undertray and the new MG4 we've received recently, they are the same so it's a characteristic of the vehicle.

Dealer called this morning. They’re refusing to do anything about mine because it’s “normal” and all the others are the same

I dont have the air scoop panel really fits very well

 

[Oberoy]

If it by design does the fact it's so variable in size/location says as much as some are have the bulge and others don't. If it was by design it would be consistent size surely.

 

[Deleted member 10041]

My dealer told me now of their cars had it, I then had a look under their demo and showroom car and both had obvious ones. It's a nonsense

 

[Steve T]

If it by design does the fact it's so variable in size says as much as some are have the bulge and others don't. If it was by design it would be consistent size surely.

Silly really that when the car comes with aero wheel trims to maximise a few percent efficiency, then dealers are saying a big air scoop is fine

 

[AndyL61]

When I finally get my car , I am going to remove the undertray, take a round file to the offending holes and see if I can get it flat. Then take pictures and send to MG to show them how it should fit.

 

[siteguru]

You may need to apply heat and some flat weights to remove the bulge as the plastic may have "set" in that shape.

 

[AndyL61]

You may need to apply heat and some flat weights to remove the bulge as the plastic may have "set" in that shape.

I was actually thinking if it's heat that is causing the bulge. Are the bulges always under the motor, and is it close enough to be affected by heat from the motor ?

 

[Ian Key]

When I finally get my car , I am going to remove the undertray, take a round file to the offending holes and see if I can get it flat. Then take pictures and send to MG to show them how it should fit.

Might have to do the same to the washers so they can still sit in the indent of the tray but allow the bolts to be off centre.
Just off to check my Dremel attachments ?

 

[AdamskiEM]

I was actually thinking if it's heat that is causing the bulge. Are the bulges always under the motor, and is it close enough to be affected by heat from the motor ?

I dunno. The brand new one on the forecourt with like 10 miles has them. Mine are on the offside, motor is on the near side isn’t it?

 

[siteguru]

I dunno. The brand new one on the forecourt with like 10 miles has them. Mine are on the offside, motor is on the near side isn’t it?

Well the breather for the reduction gearbox is towards the nearside, so that would put the motor central or towards the offside?

 

[Oberoy]

Its an interesting thought, I think the location of the bulge varies though looking at the photos that people have posted.

 

[AndyL61]

I dunno. The brand new one on the forecourt with like 10 miles has them. Mine are on the offside, motor is on the near side isn’t it?

Ok , that kind of rules that out. But if the bulges are in different places then this must be down to hole mis-alignment / bad fitting. Hopefully I can sort it myself when I get my car .

 

[AndyL61]

Might have to do the same to the washers so they can still sit in the indent of the tray but allow the bolts to be off centre.
Just off to check my Dremel attachments ?

Yes I have one of those or I can get some slotted washers made.