The importance of a working diff breather

[Michael]

So I just wanted to share one of my findings on a Patrol rear diff. The diff was whining quite a bit and I decided to remove it for inspection.

Firatly the oil was in very bad shape, looked like old diesel oil.
When I removed the sedeshafts I saw areas of rust which already gave me a hint that water must have been in the diff.
The crownwheel told the reat of the story.

All of this was due to the breather pipe that got disconnected from the breather line just above the diff which allowed water to ebter the diff.

So one tip of advice, make sure your breather lines are in working order......it might save you a diff

[iandvl]

Michael,

Thanks for the tip. I'll check mine asap.

Edit: Sorry to hear about this. :(

[Michael]

Ian, this diff is not from my Patrol but one I am working on.

But yes, I also have simpathy for the owner as the vehicle has very low mileage on.

This is so easily overlooked, but can cause major damage. I have only checked mine once ever so will also chexk mine asap

[Anthony Forgey]

Over the past few weeks I have been sorting out bits and pieces on the Patrol. I found that the breathers were disconnected near the gearbox where the flexible hoses connect to the metal ones. I checked for debris, tested for airflow and reconnected.

Water in the diff is a silent killer.

[izakjbrt]

Since I am bored and reading all threads on here....is it a waste of money installing a breather kit for the front and rear diff on the grx?

[Peter Connan]

Assuming the factory stuff is fitted and in good order, the front diff, gearbox and transfer case breathers are actually pretty good for a factory car. They all end in the left front wheel-well, the same area as the factory engine air intake.

The rear diff is a bit more vulnerable, ending in the one of the chassis cross-members, which has rubber plugs in the ends. Lose one of these and you could have issues.

If you expect to do a lot of very deep wading, it would make sense to extend them all into the snorkel, but personally I haven't bothered. Did once get water in the gearbox, but that was because the rubber boot around the gear lever had perished, and I didn't realize. At least with the auto, you don't have that problem...

[Pieter B]

On the Hardbody I owned previously I ran a rubber tube from the rear diff to the engine compartment. I have thought about doing it on the Patrol as well, but haven't done it yet.

[Craig Lord]

quote="Peter Connan" post_id=110044 time=1587057648 user_id=530]

The rear diff is a bit more vulnerable, ending in the one of the chassis cross-members, which has rubber plugs in the ends. Lose one of these and you could have issues.
[/quote]

Just a side note, those rubber plugs on the chassis crossmember that accommodates the rear diff breather are not completely sealed. I'm sure they are fine for a quick dip in and out but complete submersion would flood the crossmember with water. On the y61 at least. Not sure about the GQs

Also I pulled mine out and found alot of dirt in the crossmember. I disconnected the breather pipe and blew it out with compressed air. Might be wise to check yours also :mytwocents

[Pieter B]

How about running a length of pipe into the rear where the jack is kept? Maybe top it of with one of those petrol filters. I have my power cables from the battery running into there.

[Peter Connan]

I have been wondering for quite a while whether these things are any good:

https://www.google.com/search?q=diff+br ... Ft-UqhOn3M

I would not mount it directly on the diff, bit up on the chassis though...