Defender 90 lt77 Oil leak. PLEASE HELP!!

Hi guys! I have a land rover 90 2.5tdi engine LT77 gearbox just bought it 2 months ago and recently I have changed all the oils like front and rear diff oils, Gearbox oil, Transfer case oil, Engine oil, Filters, Fuel filter, belts etc etc.. Before the service I have noticed a few drops on the ground but I've heard that on land rovers is normal oil dripping so i didn't care much. So after the service I still have these oil leaks and they increased a bit more especially under the gearbox sub beacuse now i have a fresh new oil i can assume it's thinner. Are these normal on land rovers? I have calculated Its like dripping 5 drops in 3/4 hours idle. I have posted some photos for better ideas.. Any thing i can do accept rip the gearbox off and make new gasket? Or some instant gasket will
Solve the problem or i just leave as it is? Any ideas i appreciate!

Not familiar with the 2.5tdi but if I had to hazard a guess going on the oil colour I'd say that was engine oil probably leaking from the rear crank seal...

If it was gear oil leaking from the back of the 77 I'd also expect to see it at the join to the bell...

That's engine oil, gearbox oil is red (or at least it should be if you're using the right stuff).
At that amount I wouldn't even pay it any attention. That's nothing and isn't going to cause you any problems. All landys leak a bit, some more than others. If it gets excessive then I'd maybe look into sorting it but at the moment it's fine. As Bennehboy said it's most likely the rear crank seal which is a gearbox off job.

the bell housing hasn't (shouldn't have any oil in it so resealing won't help. As said probably rear crank oil seal.

Have you got a wading plug in? You should have a threaded hole like....



If it has the plug in and the crank seal is leaking the oil will build up and trash the clutch.

blue beasty said:

the bell housing hasn't (shouldn't have any oil in it so resealing won't help. As said probably rear crank oil seal.

Have you got a wading plug in? You should have a threaded hole like....

If it has the plug in and the crank seal is leaking the oil will build up and trash the clutch.

Click to expand...

I found it odd that I couldn't see a drain hole in any of the photos :s. Look where the oil drips are collecting. That's obviously the bottom but no hole? Wierd.

Not the clearest of photos, maybe zoom out a bit but as above, rear crank oil seal.

hi all thanks for the replies! Well yes i was thinking about that drain plug i dont have it its a bit wierd.. shall i post more fresh photos so you will be able to track down?

Worth a look!

emanname said:

hi all thanks for the replies! Well yes i was thinking about that drain plug i dont have it its a bit wierd.. shall i post more fresh photos so you will be able to track down?

Click to expand...

I'm wondering looking at your pics whether your wading plug hole has be covered over (it may just be the angle)?

It's not really a drain plug as such because there shouldn't be fluid above it but it does allow any oil that leaks from the crank seal or gearbox to escape without contaminating the clutch.

It only needs a plug in it when wading in deep water (also to protect the clutch) but is generally left open and if not needs to be removed regularly

ok posting pics soon in 20mins.. thanks again guys for your help!

Well these are my new photos of the transfer case.. This photo showing a leak from the transfer case and its drops on the floor after 2 hours and it will remain the same drops on the floor until next drive...

These are the new photos under the gearbox now showing the gearbox and its leaks on the floor. Just to let you all know I have wiped the leak with a cloth so i will know where the leak its coming from but its not showing any sign of leak till now, I think leak will go out when the oil is hot. The same as the transfer case leak, the drops on the floor are from the gearbox and are after 2 hours idle and remained the same. Strange thing is that the oil is light brown color both under transfer case and gearbox no sign of red oil

When i changed oil I have used ATF III for the gearbox and its red oil for sure and used 85w/90 for the transfer box the same oil for as the diffs takes.

T-case is probably the intermediate shaft, box out to resolve, just o-rings if you're lucky, new case if you're not... the steel shaft can make the aluminium case holes oval.

The amount of black mess in the first pic makes me think the problem is from higher up,sump seal, back of rocker box,give it a real good clean then a short run and with a good light see where oil is coming from.
I did my intermediate shaft front o ring by freeing off transfer box,moving it back as far as prop splines would allow and move shaft forward just enough to replace ring. [did not do rear as it was not leaking] Think one has to be careful not to move shaft to far forward or thrust washer may drop out.

I've got a similar looking leak to your original pics, might be rear end crank seal, I've got a leaky rocker cover gasket that eventually drips down to the floor, might be worth looking at! The leaks can start from various places (oil filter, oil pressure switch etc ), but always seem to drip in the same place!

I wouldn't rule out T seals I had a similar looking leak on my 300 tdi, changed them last weekend

What have you changed?

The rear main bearing caps have small rubber T shaped seals on the side of it. When they go they can cause a leak in between the block and the flywheel housing

I had the same leak on mine and it was the gasket between the flywheel housing and the block

Titch has just hit the nail on the head, I have the exact same leak, I have done T seals, sump seal with no success. It's not a rear crankshaft seal as that would come from inside the bell housing it is a stitch says the seal between block and flywheel housing. I've left mine until a future date when I need to do a clutch change. Oh and don't be fooled with the drips on the transfer box they are what's been blown back from the leak further forward.