I thought I'd add my thoughts about the FL2 front PTU (Power Transfer Unit):

The front PTU is not a differential: its primary purpose is to change the direct of motion by 90 degrees from the gearbox to the prop-shaft. Whilst the front right drive shaft passes through the PTU, it connects and is driven directly by the gearbox. The front differential is within the gearbox.

The prop shaft drives one half of the multi-plate Haldex clutch which is bolted to the front of the rear differential. Unless the electronic system senses the need for 4WD (very rare during normal road use), the Haldex clutch is NOT locked and the rear wheels 'free wheel'. Some sites refer to the importance of the types being the same type, size and wear depth. This was certainly an issue with the Freelander 1 which had a different form of 4WD coupling. However on the Freelander 2, I can't see how this matters much - at worst it may cause a little slip between the plates in the Haldex clutch, but I doubt the electronic system will engage the clutch as the difference in the rotational speed difference between front and rear wheels would be very small.

The most common failures of the PTU: wear of the input spline (at worse this causes loss of 4WD) or worn output pinion bearings (this causes an irritating whirring or rumbling noise most commonly heard at circa 50kph).

I acquired and stripped a failed PTU to examine the path of the oil filler channel and consider if and where a drain plug could be added. This unit appears to have been cast in 2014. I doubt the pre-2014 castings were different.

I found there are 2 large webs (not of uniform height) in the bottom of the casting which effectively splits the bottom 30mm depth into 3 pools, with the centre pool being by far the biggest.

I then observed inserting a 6mm semi-stiff plastic tube through the filler hole. It first is deflected by 90 degrees downwards, but this is because it is within a channel, it is NOT deflected due to touching the gears. The tube emerges from a square hole and naturally goes into the left pool. I could not get the tube to flip to the centre pool but perhaps this is possible with a different size or material tube but then it might contact the bevel gear. I think this explains why it is difficult/impossible to suck all the oil out. Tilting the car up at the front and up on the left may cause more oil to flow to the left pool and more to be extracted.

Regarding where to fit a drain plug: the cast boss position discussed earlier in the thread has a thickness of 10mm to drill into and tap a thread. I think an M8 magnetic plug is a good solution. It would allow oil to flow and be sucked from the centre pool. It would still be advisable to also suck from the fill hole so as to remove oil in the left pool. The base of the casting measures as approx 5mm thick.

This video short shows a 6mm semi-stiff tube with qpprox 150mm inserted through the filler hole before it 'bottoms out':
https://www.youtube.com/shorts/HfDaGsY5zHg








Last edited by Bumpf on 14th Oct 2023 1:07 pm. Edited 3 times in total

Nice little video showing where the tube goes, how much tube is inserted before it come to a stop/ and what size tube did you use please, was it 5mm

My post a couple of weeks ago was based on my research for fixing the noisy PTU on my 2013 TD4 which has travelled just 78,000km. I'm not surprised that it's happened at such low Kms since I previously had a 2011 TD4 which developed the same problem at 80,000km and I put up with the increasing irritating noise until the PTU was swapped out at 119,000km by LR under 'warranty' when the car was nearly 6 years old! It then performed perfectly until I sold it at 215,000Km.

With my current car, I thought I could hear at 50-60 kph the characteristic whirring noise of the PTU failed bearings. I got under the car and tried moving the front of the prop shaft with my hand. I could see, feel and hear 1-2mm of freeplay left/right and back/forwards. See video: https://www.youtube.com/shorts/PaAzBU0bVsc

Whilst I could probably have put up with the noise a bit longer but I knew it would get louder so decided to fix it. I felt confident that since I had caught this issue at an early stage, that the PTU gears would suitable for a rebuild.

I'm in Perth, Australia. I considered importing a refurbished unit from the UK but all options were expensive due to freight costs. Note Bell Engineering does not export outside the UK. There are transmission rebuilders here in Perth WA, including exchange units. Garages were not keen to remove/rebuild/refit the PTU as it ties up a vehicle lift for at least 2-days.

I came across 'Max' who an 80-year old engine and transmission expert and LR enthusiast, who agreed to rebuild my PTU in his workshop whilst I watched. He's a bit of a legend in the LR world. The V8 6-litre automatic Series One landrover he built around 1980 made a big impression!

I decided to remove and refit the PTU myself for the fun of it! It took me 4 hours to remove the PTU on my drive. It was straight forward apart from releasing the steering knuckle bottom ball joint. It's under compression so the usual hit with a hammer to break the taper didn't work. I had to Uber to the local Supercheap store to buy a clamp tool which I had to file to widen the jaw gap to 25mm. The tool broke the taper and then I used a 650mm length of 30x30mm angle iron as a lever to push the lower control arm down.

Watching and chatting with Max as he stripped and then rebuilt the PTU was entertaining, highly educational and a privilege. He has amazing mechanical knowledge and experience - I wish it could all be copied to a computer file for posterity.

The small pinion bearing propshaft end) was badly pitted and the large pinion bearing lightly scored. The main crown wheel bearings were both in good condition. The crown wheel and pinion were undamaged. Max fitted all new bearings and swapped out some of the shims to ensure optimised pre-load and crown/pinion engagement. He milled a flat seating and drilled/tapped to add an M8 drain plug.

He has rebuilt many Freelander/Evoque rear differentials, and a smaller number of PTUs, all due to pinion bearing failure. His view is that the issue is almost certainly due to excessive preload during manufacture.

Refitting the PTU was a straight-forward reverse process, completed with assistance from a mate in 3 hours.







Last edited by Bumpf on 22nd Oct 2023 9:25 am. Edited 2 times in total

Which oils out of these would you be happy to use in your Diff, PTU

https://www.ebay.co.uk/itm/111661700665

https://www.ebay.co.uk/itm/370757177855

https://www.ebay.co.uk/itm/303956199769

https://www.ebay.co.uk/itm/254900243768

Would you also use this in your Haldex.
https://www.ebay.co.uk/itm/174003445324

any and all comments welcome

Responding to Artic's question regarding oil:

The choice of oil for the PTU and rear diff is discussed in some detail in thread: https://www.freel2.com/forum/topic34829.html

According to the LR service manual, the recommended oil is Castrol BOT 118 Plus 75W-90.

Whilst researching alternatives, I came to the conclusion that 'BOT" is a Castrol product name since I could not find any other oil manufacturer that used this in a specification. My local 80-year old highly experienced engine, gearbox, diff expert had never heard of 'BOT' as a specification for oil. It might be a reference to 'Brookfield Oil Test' as there is a Brookfield rotational viscometer that measures dynamic viscosity, but I found no evidence of such a link.

The '118' element of the Castrol product name may relate to the kinomatic viscosity (ratio of dynamic viscosity and density). The Castrol PSDS shows this as 119.1 mm2/S) but for other Castrol BOT products there does not appear to be a similar correlation. I noted that Castrol have a Defoaming Agent Additive called 'S 118' but did not find any evidence that this is a component of the recommended oil.

As stated in the referenced thread above, there are pictures on the web showing that the Castrol BOT 118 Plus 75W-90 product is clearly stated on the back side of the container as 'SAE 75W-90, API GL-5'.

The difference between GL-4 and GL-5 seems to be well explained here: https://penriteoil.com.au/knowledge-centre...oils/1036.

I choose to use Nulon fully synthetic 75W-90 GL-5. I believe it's an Australian brand. Comes in a convenient 'Esy-squeeze' bag that can directly squeeze it into the filler hole without need for a pump or syringe. A good solution!

My FL14 went back to the dealer early this week, Monday 9th October to have the Haldex looked into due to it's slight grabbing when pulling out of a junction left quite quickly.

I collected it on 14th Saturday October 2023, a new pump and a few hours of flushing by them hoping it would fix the problem, i had already said to them that i doubt it will fix it.

Well no sooner had i drove up the road turning left out of a junction same grabbing effect, so NO it's not fixed.

Adam the proprietor says he will get it booked in with ( www.bellengineering.co.uk ) he had phoned them and they advised the flushing and new pump, to see if it fixed the scrabbling/ grabbing, he was also told to ring and book the FL2 in on the 1st November 2023 to get a date for January 2024 because they are so busy they are taking bookings three months in advance to get a date.

Anyways i checked that a new pump had been fitted, what makes you think i do not trust them while looking and taking a few photos
1

I noted on the diff a flat with an hole which to me looks like where a drain plug should be, has this been noted before by anyone please.
2

3

Which is the best one to use to add a drain plug, i know the square one has been used by others.
4

This looks just like it should be one what do others think /
5

the lower pic is where I put my drain Jules

Quote:

the lower pic is where I put my drain

Jules

@Artic

Mate it is so easy to find this info, you've even posted in this thread yourself.

https://www.freel2.com/forum/topic32683.html (Now Sold). 2008 Freelander 2 (Nazca Sand) SE TD4 Auto. Statutory write off & on WOVR for hail damage but still road legal.
171037Km as of 09/05/22
Superchips Bluefin Flash
Nanocom Evo II (also sold)

Arctic wrote:

Quote:

the lower pic is where I put my drain

Jules

Hi Jules.
Do you have a link to how you did your drain plug, what size plug, and drill & tap please.

Quote:

Badger51 wrote:

@Artic

Mate it is so easy to find this info, you've even posted in this thread yourself.

https://www.freel2.com/forum/topic32683.html

So i did job to do along will all the oils changes.

Nodge68 wrote:

Arctic wrote:

Quote:

the lower pic is where I put my drain

Jules

Hi Jules.
Do you have a link to how you did your drain plug, what size plug, and drill & tap please.

I fitted a drain plug in mine while I was rebuilding my rear diff.
It's not as simple as drilling for a plug, as there's a raised boss inside where the plug will be drilled. This means the boss needs cutting back, or there will be a puddle of oil in the bottom which cannot drain out.

Quote:

MotionInc wrote:

Update to drilling & tapping my PTU:

I used a M10x1.25 drill, tap and motorcycle magnetic bolt. In retrospect, an M8 would have been better since the drilling was centre but slightly off level, downward slope, minimal but enough to have to grind the case. Used Matco hyper-step drill bits in ascending sizes; punched the location once we marked the centre of the sump cast (see pics). Also used an angle drill with excellent trigger range speed control.

Click image to enlarge

Lots of room in that location and enough meat to drill safely. Drill slow and level.....thanks to those who have lead the way!

See my earlier post. M8 worked for me as a PTU sump plug size. As I had the unit off the car, it was easy to machine a flat surface and drill perpendicular to the surface so that I could use a standard allen key bolt with a copper washer. If you can't smooth the surface, then a rubber sealing plug might be better option.

The engineering tables show that M8 x 1.5 uses a 6.8mm drill. As it's an unusual size I bought a tap and drill pair. They probably have these in UK's B&Q. I think 17/64" (commonly available) is 6.74mm so that probably will work if tapping in Aluminum.

Having said all that, I sold the Freelander with the modified PTU and bought a 2014 SD4 SE with just 33,000km. On this new car without a PTU drain, I've just done the PTU oil change. I find that using a compressor driven vacuum (eg a brake system self bleeder) with a soft tube, I can get most of the oil out. The soft tube is able to 'jump' over the compartment barriers in the base of the PTU. See my earlier photos and the video that shows a firm tube gets trapped in the first compartment.

Even with the drainplug added, there will be oil trapped in the probably 2 out of the 3 compartments. So sucking with a soft tube is as good an option I believe.

The PTU oil is due to be changed again soon because the first change which i did in November 2023 was to me a flushing change, also my intention is this time round i will drill and tap a drain hole plug.



I have gathered the drill bits, taps, and drain plugs i intend to use, yesterday i did a dry run on an alloy mount which was surplus to my requirements.



I purchased two different sizes and types of drain plugs.



M10 x 1.0 and M12 x 1.5 Allen key type

1

https://www.ebay.co.uk/itm/255571702589?var=555518513596



https://www.ebay.co.uk/itm/255571710030?var=555518606563



Also the same in six sided hexagon bolts.



M10 x 1.0 and M12 1.5

2



https://www.ebay.co.uk/itm/295491948330?var=593586503776



https://www.ebay.co.uk/itm/295491948330?var=593586503777



Along with the plugs also purchased and tap & die set.

https://www.ebay.co.uk/itm/134268411250



I already had a few taps and handles but thought be good to get a set.

3



Used this chart to size the drills needed for the taps.

4



With the alloy mount in the vice i punched a mark for drill on it.

5



Drilling was done in differing sizes, first drill i used was a 4mm HSS

6



Next was 5.5mm drill.

6



Then a 6.5mm finally a 8.5mm.

7



This was to use the M10 x 1.0 plug

8



So started the tapping.

9



Turning the tap slowly back and forth until the hole was threaded.

10



11



Then it was time to try both drain plugs.

12



13



First was the Hexagon plug with copper washer, fitted great.

14



Then the Allen key plug with it's Rimlex Sealing.

15



Both types fitted great, so test of the M10 x 1.0 over.

16



The same process for the M12 x 1.5 mark & punch.

17



This time the 6.5mm drill was used from the off.

18



​Then the 8.5mm drill.

19



Finally the 10mm drill.

20



The hole was ready to tap, 12 x 1.5

21



22



Again slowly back and forth until the thread was completed.

23



24



With the thread now done it was time to try the plugs.

25



26



27



First the Hexagon plug.

28



29



Fitted great once again, now the Allen type plug.

30



31



32



Photo shows both the M12 x 1.5 on the left and the M10 x 1.0 on the right.

33



The same for the Hexagon plugs.

34



Hopefully the drilling of the PTU and tapping will go smoothly waiting on a nice warm day now.

35