Mk8 Zetec Gear Oil

[HRF1T2020]

Hi

MK8 Fiesta Zetec 18 plate

Question on gear oil level

On all my previous cars including previous Fiesta s, gear oil is filled to when it just starts to dribble out

The Fiesta states that oil should be 20mm below the fill level bung, is this done for a reason in a three pot engine or to save oil?

Can it be topped up to the bung level

Thanks in advance

[dezwez]

i would top up the same way as gear oil cant do it any harm 👍

[HRF1T2020]

Thanks so filling gear oil level until the filler level drips out, always known it this way.

just can't work out why it would state 20mm below on the mk8 gearbox seems a large gap to mme.and why Ford would fill to that level?

 

[HRF1T2020]

Anyone know why gear oil is to be 20mm below the bottom of the top up hole on the gearbox?

I'm still in the mind to fill to level any ideas plus or negative in doing this

[DG97]

I don’t personally know the advantages or disadvantages but as above, gear oil unlikely to do much harm anyway but if it gives a specific instruction to fill an x amount of oil, why not just put that in and you’ve then stuck by exactly what is says on the tin? 

[Eng_Ahmad1986]

I think overfilling gearbox oil could increase pressure inside the gearbox that the breather can't handle, increasing the probability of damaging the CV joint shafts seals fitted on the gearbox, I would stick to the manufacturer's specifications

[HRF1T2020]

Yes seems right analagy and will leave at current level

Just if you look accross the different models mk7 etc they have same gearbox but different recommended levels some 5mm 10mm now 20mm

Latest ones are dropped to 20mm seems weird that it was 10 or 5 mm before but now 20mm,

cannot find any info as to why that would be got me thinking are they saving oil accross the fleet? Or is it in response to issues in the past, if so then at service gear oil should be reduced via a TSB can't find any for that either🤔

And after warranty thousands use independent garages whom I'd presume would top up the gear oil to the drop stage thinking it was underfilled

Thanks for all the input

[tomshepp]

It won' t be oil that is being saved but fuel. Churning unneccesary oil wastes power and if the box will work properly or even better  when cold, perhaps, then why not? The 6 speed is still relatively new and it would not be unusual for Getrag to use a more cautious specification until the gearbox is proven in use.

[HRF1T2020]

Yes I see what you mean on the 6 speed but on the proven 5speed it's been reduced over the years

I guess as you say reduced to hit better fuel savings in the 3 pot engine which on my 18plate zetec is 51mpg so adding oil would reduce that, but is that at a trade off at having 10mm or 20mm less oil in gearbox potentially reduce the life of it?

[tomshepp]

Not if the gearbox is adequately lubricated with 20mm less.Lubricant formulations change, too. You wouldn' t expect Castrol GTX to last 12,000 miles in an ecoboost but modern synthetics do. Gearbox oils are now very different to those of 20 years ago.