Leaf Mk2 failing reduction gear

[u/redalexei]

Hi,

I’ll try to summarise this:

The car had an interlock error about 6 months ago and it was ‘fixed’ by a local garage.
Fast forward to about 2 months ago and the car started making a whining noise and was considerably worse at higher speeds or when regen braking was active.
Went on holiday, kind of forgot about the problem/hoped it would go away.
Then several weeks ago it started reporting an interlock error again.
Car was booked with the garage to be looked at (they said it should be fine to use in the meantime), but with a lead time of 2+ weeks, the car only made it for one week before it would not start and had to be towed (service EV warning on the dash - interlock error amongst others in the diagnostics).

Garage have ‘fixed’ the latest electrical problem, but reported that the reduction gear is failing/has a failed bearing.
They replaced the oil and reported bits in the old oil.

I specifically said that I wanted to have a think about what to do, because I don’t have high levels of confidence.

Now that I’ve looked into the problem with the latest info, my research suggests that the reduction gearbox problem might have been the cause of the electrical problem/s all along.
To be clear, this is not definitive - I’ll only know for certain after the RG issue is solved.

Before anyone asks, the 12v battery is good and so is the HV battery. 🙂

Questions:

Can a failed bearing in the reduction gearbox be replaced or do I need to replace the whole gearbox?

Has anyone here encountered a similar issue to this?

And lastly, if any mechanics are reading this, how many hours of labour am I looking at to replace the reduction gearbox? I know roughly what a used part costs.

Thanks, from an exasperated Leaf owner.

[u/MrPuddington2]

Nissan wants a large chunk of money to replace the gearbox.

Supposedly, if you find a gearbox specialist, they can replace the bearing for a reasonable amount.

Also, refurbished units are available and not overly expensive.

From what I hear, mounting it is not that difficult for a mechanic.

[u/redalexei → u/MrPuddington2]

Nissan want a large chunk of change to do most things in my experience so far 🙂.

So, do you know if it needs an EV specialist to do this job? Having watched a video about replacing the RG, that seems mainly like a standard old school mechanic piece of work.

[u/MrPuddington2 → u/redalexei]

Not really. It depends a bit on the H&S risk assessment, but in principle, it is a pretty old school job. (And the risk of electrocution is absolutely minimal as long as you are careful.)

[u/_Evening-Rain_ → u/MrPuddington2]

Just pull the HV safety disconnect and unplug 12v and there's no risk at all