Although this relates to my 54 plate Discovery 3, I am pretty sure its the same for a 2.7 RRS of the same age, hence the question.

I changed the oil pump on my D3 following an oil leak of Torrey Canyon proportions. I thought it was the front seal but it was actually from the passenger side upper part of the pump (not a FoMoCo one sadly).

In removing the old one, the upper sump gasket looks in bad shape where the pump body slides over it, and it looks like its been pushed back a little over the hole where the pump pulls from the sump.

I am concerned and not wanting to risk the engine (190k miles and always strong apart from the oil leak), I am planning to replace the upper sump gasket.

From a first inspection and a bit of research (there is not much on the internet on this it seems) it looks like:
- starter needs removing
- various bits and pieces like turbo drain have to come off
- dips stick tube needs raising up


I think I can see all the upper sump bolts, and once removed, it may drop far enough without removing the front diff to slide the gasket in and re-assemble.

Has anyone else done this who could offer advice? If I can get access, is it worth popping in new big ends as a longevity measure.

Any thoughts appreciated. Apologies again, its a D3 question, but I believe its mostly the same under the RRS V6.

Have you got the workshop manual? Be worth downloading it if not. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Remove fan and aux belt
Remove aux belt tensioner bracket
Remove radiator plastic surround
I had to pull out 2 tiny tubes off the steering rack (so have some cold climate fluid handy.
Then the upper sump slides forward and up by the rad

Don’t completely extract the dipstick tube from the engine bay. They are a nightmare to rethread in

Click image to enlarge

Awesome, so it comes out the top?

Any issue with the rear bolts by the gearbox and starter motor?

From memory, the front diff has to come out to lower the crankcase down

Wondering if the crank case can be lowered just enough to slip the new gasket in, but now problem dropping the diff if I need to.

I’ve got it out without removing the diff.

But as said, took some small pas pipes off.

No issues with rear bolts

That's good news. I think I am going to start again from scratch with timing belt and oil pump off, then crank case off, then remount the pump and time it up then crank case back on with new gasket to seal from below properly.

It's a weekend but I want to get it done properly.

Worth changing big ends at the same time?

personally I wouldn't remove the oil pump.

Fitting a pump after the sump, means it kinda scraps along the gasket. (a little)

Where as if you just remove the sump and fit a new gasket, it should go on a nice flat surface.

Regarding shells, I guess that depends on whether you can source good ones, and how good you are at fitting them !

Been working on this today. I can't say it was an easy job, but I guess that is to be expected!

I decided to take the oil pump off, as with the potential of a restricted oil flow, I wanted to check all was OK with it. That part of very easy, and for re-assembling, I am pretty sure I can put it on before re-assembling the sump.

The painful bits were the passenger side of the engine. Two bolts holding the lower turbo mount to the top of the sump, marginally accessible through a small opening in the wheel arch, but almost blind to get to with the prop in the way. Similar with the A/C compressor bolt that goes into the upper sump.

Never-the-less, the upper sump is released but I cannot figure out how to remove it out the front. The left and right higher portions that the starter bolts to and similar on the other side are too tall to fit between the block and front diff.

I think to re-assemble and make sure it is cleaned and the gasket fitted correctly, I will remove the diff. I have already undone the front prop so I could get a little more room on aforementioned turbo mount bolts. I have also removed the chassis arm below the diff. Just need to pop the drive shafts, drain it, undo the 3 mounting point and lower it. it will make the re-assembly much much easier.

I must admit I am temped to drop the big end caps to see what is going on. Everything looks very clean and pristine in there as it should.

A further note on this.

REMOVE THE FRONT DIFF

Learning is everything, and I really wish I had removed the front diff right at the start. Its a relatively easy job, allows the front suspension, drive shafts, and brakes to all be inspected, and the time taken is easily made up from through lack of pain, not needing to be a contortionist, less cursing, and time gained through ease of access.

I removed the front diff as there was no way I could see of getting the upper sump out once it was free, or back in again without making it dirty, dropping grit from the upper engine through it, or ensuring the new gasket was correctly located.

A clean re-assembly without the diff in the way was so easy. Things the diff would have caused issues with included refitting the turbo drain pipe, refitting the dip stick tube and getting the 2 bolts back into the turbo support bracket. The front prop is also more mobile without the diff being there giving more room for refitting the lower bell housing bolts. So much easier!

With regard to the big ends, I decided not to replace as the car was working fine before taking to bits, but I did do an oil pressure check using a calibrated gauge (in the oil pressure light switch location) when it was all back together. Cold, I got 28PSI at idle and 62PSI at 2500rpm which from the info I have looked up, is within spec suggesting oil pump and bearings are doing their job.

Thanks to all who made comment on how best to approach this. If anyone else chooses to do the job to solve oil leaks, or if the upper sump gasket below the oil pump is damaged due to removal and refitting of an oil pump, then I can absolutely recommend removing the front diff.

Worth noting also that I am a home mechanic, and this was done with the car safe on stands and me on my back. No real need for special tools other than a couple of decent torque guns (battery and mains), fan spanners, big joint splitters, and a good range of decent large spanners and sockets (and a calibrated mechanical oil pressure gauge).

Hey! I have a disco 3 and notice this thread may be applicable.
The seal was damaged when I removed the old oil pump and this seems to be the way to go for me to fix it.

You’re in hunts...any chance you’re going to be down herts way any time soon? I’m belts off oil pump off and seal damaged’ far into this and I’m at wits end. Want to get this sorted ASAP and not sure I’m confident enough following this thread not knowing what the parts look like and where they’re located.

I’m not a complete idiot, I recently did the front two air struts, reservoir, compressor, and front and rear valve blocks all is now perfect with suspension!

Any chance you could ping over some threads, pictures, drawings, or yourself to give me a hand I literally might cry. I ran out of curse words getting that damned starter out!!

Not sure ill get down to Herts in a reasonable timeframe to be of any help, but it sounds like youve made all the right progress in getting the oul pump out so its not such a big job from here.

Ill type more tomorrow but it sounds like next stepis getting the diff out of the way which starts with getting the front end high and secure on axle stands, then 3 stages, front prop, left drive shaft, right driveshaft.

As a starter, I undid both ends of the prop, transfer box end first as the access for the prop bolts that end up on top is a bit easier and then you can rotate it to do the diff end. Prop compresses enough to drop it down or push it up and slide it back a little soits out of the way. More tomorrow!

Fantastic! Shame you can’t be around but what you’ve sent is already making me feel more comfortable about moving forward with this, and so I look forward to any more advice you can offer, much appreciated, thank you!

No problem at all.

Next two jobs are left and right hand drive shaft.

- Front wheels off
- Drain the diff. 14mm hex
- Remove the brake calipers and tie them back in the rear of the wheel arch out of the way. I used bungy cords for that. The brake pipe mount on the upright needs to come undone. 10mm short bolt that will be corroded so plenty of penetrating oil. A tap with a hammer sometimes breaks the corrosion lock, or tightening a tiny bit first. I always use a 6 point socket on stuff like this to avoid rounding the head
- Carefully remove the ABS sensor. 8mm bolts which again can corrode, and carefully prise out the sensor. They are a sensible design so tend not to freeze in the hole. Get them both out of the way.
- Impact gun or big bar (I had to use heat on one) and remove the drive shaft nut. A fine centre punch or old study screwdriver to open the tang first. I forget the socket size but 32, 36 or 41 maybe?
- Undo the 18mm nuts on the track rod ends, and the upper wishbone. Top tip for me here is while the taper joint is locked, remove the nut and clean up the thread in the nut and on the ball joint. If the taper lock breaks and it starts spinning, its an allen key into the end of the ball joint thread, and this is often full of dirt and corrosion and rounds off easily, and then youre stuffed.
- Big ball joint splitter, or two hammers, and split the track rod end and upper wishbone ball joints. The upright and hub then swing free and with a bit of pursuasion you can get the drive shaft out of the hub.

- On the side of the car where the shaft goes straight into the diff, gentle prising with a log screwdriver/pry bar each side of the flange should relead the drive shaft from the diff. There is a spring collar on the splined shaft that goes into the diff that needs compressing as the shaft is removed. That is what will give you the resistance against removal. It can take a bit more than gentle and will sometimes let go sharply, (causing knuckle abbrassions!!!). Don't pull on the driveshaft to do this as all that will do is pull the spider out of its cup on the diff end of the driveshaft.
- Driveshaft can then be lifted out and put somewhere safe.

- On the other side of the diff there is a support tube held to the diff by 4 13mm bolts, and a bolt to the chassis at the other end. Remove these, and carefully wiggle and rotate the support tube so that the lug bolted to the chassis is no longer interfering with the chassis, and the support tube has slid out of the diff. There is a large skinny rubber O ring seal. Don't damage or loose this.
- Same approach as the other side, should be able to prise the entire supported shaft and drive shaft out of the diff. It is long and unweldy so care needed not to get dirt into it.

Now the diff itself can be tackled