Transmission Drain Plugs

Hi,

With the finer weather and a bit of spare time, I've started work on changing over all the fluids in the drive train. My first job has been the rear diff. Cover is over, oil drained (relieved to see it looked quite clean - but would have expected a little more of it).

Now, I have a quick question re the magnetic fill plug... When removed, it didn't have much in the way of metal on it. But it did have what looked liked a smear of some kind grease over the magnet. So when I refit the new plug should some kind of grease be smeared on it?, (presumably it's to help retain any metal bits, on the plug, or was the gunk I saw a result of the warm oil reacting with very fine metal particles on magnet, making a greasy paste?)

I've looked at Rave and it just says to refit the rear diff cover using RTV for the mating surfaces, and thread lock for the bolts.

Many thanks

Jim

The plug goes back in clean. Nothing is put on to collect the dirt. There's little point in putting a magnetic plug at fill level anyway, which is why there was almost no metal particles on it.
By far the best way is to have a magnetic drain plug, which the Freelander doesn't have, unless you add one

Thanks for the quick reply. I will put the new one in clean.

I guess it only does it's job if parked overnight on a very steep hill!

Must have been a cost cutting exercise for them to not put one in at the bottom of the casting, for the space is there. Hopefully I won't need to remove that cover again for a while, as peeling off the silicone is bl***y awkward, especially on the top two corners where the rubbers from the diff mounts get close to it.

The next fun job after getting the cover back on and bolts tightened, will be filling the damn thing again

Thanks again, Jim

4Bee4Bee said:

Thanks for the quick reply. I will put the new one in clean.

I guess it only does it's job if parked overnight on a very steep hill!

Must have been a cost cutting exercise for them to not put one in at the bottom of the casting, for the space is there.


Thanks again, Jim

Click to expand...

I have fitted a drain plug in the Freelander rear diff. It's not difficult as the space is there.
It's not worth doing as a matter of course though as the cover comes off so infrequently.
It would be beneficial to fit a powerful neodymium magnetic washer to the bottom of the casing, held in place by an allen bolt.

Nodge68 said:

I have fitted a drain plug in the Freelander rear diff. It's not difficult as the space is there.
It's not worth doing as a matter of course though as the cover comes off so infrequently.
It would be beneficial to fit a powerful neodymium magnetic washer to the bottom of the casing, held in place by an allen bolt.

Click to expand...

Hi Nodge
Do you have any pics of said drain plug you fitted and how please cheers Arctic

Arctic2 said:

Hi Nodge
Do you have any pics of said drain plug you fitted and how please cheers Arctic

Click to expand...

I didn't take any photos when I did it.
It wasn't difficult to fit however. I drilled and tapped a 10mm thread onto the flat section on the bottom of the diff case. I then counter bored the 10mm thread out to 16mm about 6mm deep. This allowed me to fit an allen socket bolt that sat flush to the bottom of the diff case. I used a thin 10mm copper washer as a seal. It worked as intended and didn't cause any other problems. The diff casing at the bottom is about 25mm thick, so weakening the casing isn't an issue.
I got the idea from a friend who was using a Freelander diff in a home built kit car.
There may be some pics on the web

Nodge68 said:

I didn't take any photos when I did it.
It wasn't difficult to fit however. I drilled and tapped a 10mm thread onto the flat section on the bottom of the diff case. I then counter bored the 10mm thread out to 16mm about 6mm deep. This allowed me to fit an allen socket bolt that sat flush to the bottom of the diff case. I used a thin 10mm copper washer as a seal. It worked as intended and didn't cause any other problems. The diff casing at the bottom is about 25mm thick, so weakening the casing isn't an issue.
I got the idea from a friend who was using a Freelander diff in a home built kit car.
There may be some pics on the web

Click to expand...

Excellent thank you for explaining, a project for me in the near future

Arctic2 said:

Excellent thank you for explaining, a project for me in the near future

Click to expand...

You are welcome.
I didn't fit one into my current Freelander's diff, when I changed the oil recently.
I couldn't lay my hands on my tap set, or I would have done it.
I suspect it's actually faster to drill the bottom, tap the hole and fit a plug, instead of removing the rear cover, cleaning the sealer off, adding new sealer and refitting the 10 or 12 bolts.
Maybe next time.

You were right Nodge, wasn't too difficult at all, getting the syringe lined up with the fill hole, (just fed it over the subframe, and under the exhaust). So, after doing a few journeys totalling ~50 miles, all nice and dry under the diff still.

If I have to take the cover off again in the future, I may drill and tap a bolt hole underneath, to future convenience. For anyone considering this before they carry out a rear diff oil change, here is a photo of the bottom of the unit with the cover off, showing there is a bit of space internally, and there is some meat on the casting to do mod Nodge68 has outlined.



Right, next job when I get a moment is the gearbox and IRD oil changes....

Jim