The underside of my new-to-me '00 Disco II is a wet oily mess, nearly front to back. There's literally oil coating the underside of the engine, transfer case, both diffs, etc. I think the only thing that doesn't visibly have oil caked on or leaking from it is the transmission pan. At least from reading various topics on the forum, I know that if there's oil under it, there must at least be SOME oil in it!

I know oil leaking from the engine will readily coat the underside of a vehicle in a heartbeat at 65 mph, making the differentials and everything else in its path look like they're leaking.

How can I tell if it's the differential that is leaking on my Rover? I'm pretty sure it is, as there's some oozing around the seal where the driveshaft enters the housing. Is this common? I wouldn't expect oil from the engine to be in those areas.

Supposing it is leaking from the differentials, how do I fix it? I plan on going through every seal and gasket and can do all the engine gaskets & seals, transmission / transfer case, all that jazz, but I've never, ever touched seals on a differential, so I'm a bit in the blind here. Any suggestions / input would sure help me out.

I'm not driving the disco at the moment until I get the majority of the 60k service done, and front driveshaft rebuilt (it's already failed once on a previous owner, judging by the welded transmission case and blast damage all around it). I'd like to avoid replacing the diff fluid only to have it leak out all over my driveway.

But hoping to get all this done the sooner, the better, as my trusty backup vehicle gets about 10 miles per gallon on its best day. Those complaining about their Rover's gas mileage can borrow my '85 Ford F-250 with carbureted 460 V8 for a week, and you won't complain after! Fuel mileage sucks, but at least the parts are cheap!

 

get some leak finding additive. it glows in black light/fluorescent. it makes the task much easier.

 

"there's some oozing around the seal where the driveshaft enters the housing. Is this common? I wouldn't expect oil from the engine to be in those areas.
Supposing it is leaking from the differentials, how do I fix it?"
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Of course, that would be differential oil seal, though you very well may have other contributing leaks too. Diff. oil seals don't last forever; are cheap; need changing when they begin to leak. If you would like me to tell you how to change it, send me a PM.

 

personally i would start by douching the whole truck down, so you know how many leaks and from where.

 

First best to start right there.. clean off the entire underside of the truck. Go from there.

 

It is a great rust inhibitor. I think that was LR's reasoning for leaving so many gaps in the fitment. And, it keeps the dust down on your gravel driveway.

 

You: "It is a great rust inhibiter. I think that was LR's reasoning for leaving so many gaps in the fitment. And, it keeps the dust down on your gravel driveway."
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You make it sound as if this is expected from all Rovers; a natural thing you can do nothing about. BUT NOTHING OF THAT IS TRUE. It is true, perhaps, on Rovers that have had little or no long term maintenance; simply allowed to get in their present leaking state.
My 2004 Discovery, doesn't leak a drop, ever, from anywhere; if it did, I would do needed repair/replacement of bad gaskets/seals, whatever. Fact is that during dry summer months, my undercarriage gets a buildup of dry dirt, dust like powder, so I use a washer to wash it clean; never see any lubricants leading. Everyone reading this could have the same situation with their Rover, if they wanted it---it only takes some maintenance---very little, once you get it dry in the first place.

 

If your diffs are leaking it's probably time to add air locking diffs...

 

................LR's answer to Waxoyl................

 

When they are new or well maintained they don't leak too much. But, in 40+ years of LR ownership it's a common problem. It's not the quality of engineering or the OEM equipment at fault it's a function of usage and age. In my experience, 9 out of 10 LR's puke out oil from somewhere at some time. You can chase your tail fixing leaks but if they are just slight weeps it's easier to live with them. If, however, they are leaking an appreciable amount from seals or gaskets sufficiently to leave oil puddles on your drive then you have a problem as if it leaks while stationary think how much it leaks when moving and that ain't visible. If it's a diff leaking and spreading oil along the length of the truck it's probably serious, or, as has been suggested, it could be more than one leak. Personally, I'd get it cleaned off underneath with a steam cleaner and put some oil compatible leak seeker in the diffs, tranx and engine and look for any leaks with a blacklight as Dusty suggested. The only PITA seals to change are the crank and autobox seals, the diffs and tranx box are relatively easy once you pull the drive flanges. The handbrake end is a bit of a pain though. Keep a check on the oil levels though as a lunched diff or transmission costs serious $$$$$ and can throw you off the road into a ditch PDQ at best.