^^^Try a search for a thread I believe might have been started by p_gill re the front diff I think? If memory serves me, he drilled & tapped parallel into a lower bolt to drain the the PTU?

As we are talking about the rear diff here, I could be totally off base.....still a thread worthy of a careful read however.

Yes Alex has an image of the inside of the rear diff case. Just wondering if anyone has successfully gone in this way. It could be an easier solution. I have done both the front transfer case and the rear diff as per original posts but I have since had the rear diff changed so am looking to put a drain in the casing of my replacement one.

I did remove a bolt and drill a hole for the PTU.

Using this method on the rear differential housing is more challenging.

I can post a link to that thread if you want to see how I did it.

I haven’t modified my rear differential yet.

Thanks

Paul

Here is the link

https://www.freel2.com/forum/topic14659-15.html

Thanks

Paul

Yes.......I have also done the PTU mod using your directions as a guide. Thanks for posting them

but it's the rear diff I am asking about

No worries.


For the rear diff the drilled hole will need to be at an angle.

If you drill straight in like the PTU it won't break thru.


Let us know if you complete this modification and how you do it

Thanks

Paul

Without actually seeing the inside of the case, it's unlikely I shall go down the drill into bolt hole route. Just wondered if anyone has done this.

From MrRover75's gallery

I just looked closer and it does look like you can remove the bottom bolt and drill through the housing just like the PTU.

Good Luck

Paul

Click image to enlarge

Click image to enlarge

Click image to enlarge

Click image to enlarge

Paul Thanks for that info...so you do it first.

^^^LOL! It's a tense sphincter procedure.

Take lots of pics Paul!!!

Today my FL2 had its rear Diff oil changed first time since it was purchased by me in 2017, i do not know if it as ever been changed before.

The route i took was to use a suction pump which worked quite well, 625ml / 630ml removed, colour was dark brown as opposed to the golden brown when new, i used 75w/90 oil link below.
https://www.ebay.co.uk/itm/5L-Fully-Synthe...SwNotdpB9N

The filler plug was removed using a good 13mm socket and long ratchet.
1

2

Plug looked fine no sludge on it.
3

Set up the suction pump connected it to spare battery and started the pump.
4

5

6

Oil didn't take that long to remove.
7

New copper washer used, i did think of using a magnet but did not feel safe too just in case it came free into the diff.
8

9

10

Hand pumped 670ml back in to make it run out of the fill hole.
11

12

Then removed 62ml using a syringe to bring it to the level i think should be 750ml as the new oil will be mixed with the little amount of old oil left in the Diff, i will repeat the process come spring, when i may opt for the drain plug modification?
13

14

Cleaned around the filler plug with carb cleaner.
15

The oil change was done with the FL2 on four ramps so it was level.
16

Tomorrow i will do the PTU & hopefully the Heldex oil and filter.

merlinj79 wrote:

Did this mod today, went fine. The drill grabbed and bottomed out as it broke through, I was afraid I'd hit something internal but it looked like it just hit the side of the case where it necks down.

Tapped carefully, then flushed it out with a L of fluid before filling with another L.

I used a Goldplug MP-02 magnetic plug for the new drain.

I switched to AMSOIL Severe Gear synthetic oil, not really comfortable with OEM dino juice given the problems with that diff. Will change every 40K.

About 600 ml drained out, and then I used a hand pump to see how much more I could get which was another 100 ml. So basically got most of it through the drain hole. The old fluid was pretty dark but not pitch black (30k on a new Diff with OEM oil). It wasn't very hard to pump it out (unlike some cases) so it might be better to just do that rather than drill and tap.

I tried to install a Goldplug AP-05 for the fill hole, so I could check for metal periodically without draining the diff but the head on AP-05 was too wide. Might be able to make it work with several washers but the washer that came with it was too wide as well. Caveat, Goldplug did not advertise AP-05 for this application, I was experimenting. I'll try to come up with something magnetic for the fill hole. Could not find the AP-05S.

Hi Jules, excellent work there as I always love seeing engineering ie the use of taps etc, what ceases to amaze me though is, kwe all know whatever oil is out there eventually it requires renewing, so with the excellence of landrover’s expertise plus design why on earth do they not put a drain plug in from manufacture. Lifetime oils are not available as of yet especially in the motor industry. Maybe I’m wrong but for piece of mind new oil is far cheaper than a replacement.
Do they think they’re going to sell more components because of this?

I remember my early days with Mercedes G wagons as there were drain plugs everywhere even drain plugs on gearbox bell housings to let water out, plus they had a very low failure rate too of anything apart from the timing chains on some 4 cylinder petrols but they soon put that right by fitting an extra spray nozzle to soak the chain in oil, that aftermarket job was a drill and tap to complete the recall.

Looking at your finished photo, I would manufacture some sort of robust shield to protect the plug head from the possibility of damage from sliding over something.
Again excellent work!!!

Rgds DaveP.

They (JLR) don’t recommend oil/fluid changes for transmission components simply to make the cost of ownership for company cars seem less expensive which means that companies will offer the cars. By the time a fault occurs the car is on to its second or third owner and JLR can wash their hands of the whole thing and offer you a whole new component/car.
Other manufacturers who use the same components do recommend oil/fluid changes. Probably why there is a convenient flat spot to drill and tap a drain plug position on the castings.
Like many more knowledgeable owners, I prefer to extend the components life by changing the fluids.

merlinj79 wrote:

merlinj79 wrote:

Did this mod today, went fine. The drill grabbed and bottomed out as it broke through, I was afraid I'd hit something internal but it looked like it just hit the side of the case where it necks down.

Tapped carefully, then flushed it out with a L of fluid before filling with another L.

I used a Goldplug MP-02 magnetic plug for the new drain.

I switched to AMSOIL Severe Gear synthetic oil, not really comfortable with OEM dino juice given the problems with that diff. Will change every 40K.

About 600 ml drained out, and then I used a hand pump to see how much more I could get which was another 100 ml. So basically got most of it through the drain hole. The old fluid was pretty dark but not pitch black (30k on a new Diff with OEM oil). It wasn't very hard to pump it out (unlike some cases) so it might be better to just do that rather than drill and tap.

I tried to install a Goldplug AP-05 for the fill hole, so I could check for metal periodically without draining the diff but the head on AP-05 was too wide. Might be able to make it work with several washers but the washer that came with it was too wide as well. Caveat, Goldplug did not advertise AP-05 for this application, I was experimenting. I'll try to come up with something magnetic for the fill hole. Could not find the AP-05S.

Update, first oil change since the mod, at 40K.

No issues with the drain, the amsoil was dark with just a hint of color so I think I like my arbitrary OCI.

No metal swarf or chunks like what I found the first time, so I'm writing that off to poor quality control at the factory. The magnetic plug had the usual amount of very fine ferrous sludge that you'd expect.

I had ordered some washers for my drain plug but they got misplaced in a recent move. Fortunately it turns out the engine oil drain washers for my Acura are just the right size, got lucky there.

Also did the haldex fluid and filter, that was the same color, also 40K.