[B]Possible Oil/Fluid Leak Diagnosis - Photos[/B] (1 Viewer)

[Ryno80]

Hi All,

Thought I would get some info from the brains trust once again!

Just recently came back from a weekend away and have noticed afterwards that there seems to be a fair bit of oil/fluid around the rear diff, all over the shocks, coils and the under body of the car from the rear of the fuel tank back. There is quite a lot of it there and I was wondering what it could be. I figured it's not from the diff as this all looks pretty sturdy (I could be wrong). Is there anywhere else I should be looking as I can't seem to trace it to a particular spot?

Does anyone have any ideas as to what may be the most likely culprit? Maybe the brake lines?

It is a 1991 Landcruiser GXL Turbo Diesel.

Pictures are attached.

Cheers,
Ryno

 

[ajax1]

Breather on top axle

 

[Ryno80]

What may be causing this to leak?

FYI - I have extended diff breathers installed - running to the front of the car under the hood.

 

[greentruck]

That's a lot of oil to be from the breather.

I can see the front of the rear axle housing where the driveshaft enters, but I can't see clearly if there's evidence of it leaking. That's where you'll find it leaking if the pinion seal is bad, which will produce a pattern much like in the pics.

Of course, it could be dry at this point. Have you checked the fill plug to see what the rear diff fluid level is?

 

[Ryno80]

It does seem to be quite a bit of oil - that's why I'm a little worried.

I think you may be right as I have noticed some leaking where the drive shaft joins to the rear axle before. At the time it was only a quick look, a couple of days later when I had time to have a proper look it had dried all up.

I will be able to check the fill plug tonight to see how much oil is actually in there. I'm expected it to be quite low, given how much seems to have leaked out.

Is the pinion seal a relatively simple fix or something more complex?

Thanks for your help Mike!

 

[LFD2037]

Seeing as as you travel forward it will all be blown back from road wind I'd start @ the furthest forward point of where it's sprayed. You should find it easily. Does it smell like diesel(you said it's a diesel & it starts @ the fuel tank)?

 

[kerrye]

Looks like diesel to me and not gear oil.

 

[Ryno80]

Yeap that's what I figured - the fact that it blows so far is the main reason I'm having trouble finding the origin - it's just gone everywhere.

It definitely doesn't smell like Diesel, this is something I immediately checked. It does seem to go as far back to almost the fuel tank though.

I'm going to check the diff oil level tonight to confirm whether or not some has leaked, this being the case I think as Mike suggested, the Pinion seal will be the next port of call.

Appreciate the help mate!

 

[LFD2037]

If it's the pinion seal it will be obvious looking @ the diff because the fluid will be running down the front of the diff(unless it's super low on fluid). If it's that bad then there will be a puddle under the pinion(unless it's super low on fluid). It looks really runny/wet & gear oil is thick. I'm guessing it's something else but it's easy to check diff level & look @ pinion seal. And if there is ANY fluid splashed in FRONT of the pinion seal then that's not the culprit.

 

[greentruck]

What has me worried is the clean look around the pinion in the second pic. Maybe that's the area that got wiped? If so, and there's nothing in front of it spewing, then that is the source.

Thing is, back there is a long way from the engine bay. The transmission is another possibility, of course, the transfer case rather much an outside shot as they're kinda hard to damage. All of those would give obvious streaking to get back that far. And in that location, if it's not fuel, the pinion seal is pretty likely.

If it is the pinion seal, there are write-ups here on doing it. It is a bit more involved than a lot of fixes and if not done right, you get to do it all over

I had a FJ55 with a small-block Chevy V-8 and it was hard on pinion seals, thus my unfortunate expertise in this area. I took it out for the work, more than I wanted to deal with. Anyway, glad to be of assistance, I'm sure you'll get to the bottom of it with a little more investigation.

 

[Ryno80]

Just had a chance to have another look and thanks to all your advice I think I've found the source. As you can see by the pic below all the oil is to the rear of the pinion seal.. there is nothing on the other side of the axle or anything further forward. Do you lads agree?




Secondly, I think I may have found the same problem with the centre diff.. exactly the same symptoms as the rear. I have put a few pictures below. The clean side is on the rear of the centre diff and the dirty side on the front. Any ideas? Is this the same issue?

 

[jhamby]

My truck has the exact same issue - 97 HZJ80. Oil all over the rear end, hard to locate the source from just looking around. We start pulling everything out in a few days after paint is done.

Initially thought it could be diesel due to the amount, spread, and where it started. My guess is pinion seal, time will tell.

 

[greentruck]

SNIP

Secondly, I think I may have found the same problem with the centre diff.. exactly the same symptoms as the rear. I have put a few pictures below. The clean side is on the rear of the centre diff and the dirty side on the front. Any ideas? Is this the same issue?

The seepage on the transfer case side of things doesn't look wet or recent enough to account for oil further back.

That said, if the rear axle pinion bearing is on its way out, too, in addition to the seal, it may cause enough vibration to cause issues on the other end of the driveshaft. I don't think that's the problem here, though, as the oil in these pics just doesn't look fresh or extensive enough.

The key here will be the rear diff oil level once you get a chance to crack open the fill plug and probe to determine the fluid level inside.

 

[Ryno80]

My truck has the exact same issue - 97 HZJ80. Oil all over the rear end, hard to locate the source from just looking around. We start pulling everything out in a few days after paint is done.

Initially thought it could be diesel due to the amount, spread, and where it started. My guess is pinion seal, time will tell.

Yeap - I've had the same difficult locating the source. Definitely not diesel mine, it's way too thick and has the distinct smell of gear oil. Let me know what you find mate!

 

[Ryno80]

The seepage on the transfer case side of things doesn't look wet or recent enough to account for oil further back.

That said, if the rear axle pinion bearing is on its way out, too, in addition to the seal, it may cause enough vibration to cause issues on the other end of the driveshaft. I don't think that's the problem here, though, as the oil in these pics just doesn't look fresh or extensive enough.

The key here will be the rear diff oil level once you get a chance to crack open the fill plug and probe to determine the fluid level inside.

The truck is parked on a reasonable hill facing downhill so maybe that's just some of the excess rear diff oil flowing forward? I have noticed two little puddles, one right under the rear diff and around the centre diff transfer case area.

I'll definitely be checking the fluid level this arvo - just haven't had enough time lately to have a real go!
Is there anyway, if the diff oil is low, that I'm able to determine whether the bearing is actually the culprit which is causing the seal to wear out?

 

[greentruck]

Oftentimes just the seal will fail. people here have reported success just replacing the seal. The issue is that rear diff input shaft has preload on it, there's a crush sleeve IIRC, etc. But I have heard of folks marking the nut, taking things loose and then reinstalling the nut torqued back to the mark to preserve the preload without more extensive disassembly. Not the factory way AFAIK, so YMMV, but search here should bring it up. I'm just going by memory so probably best to check out what others have written up.

If the bearing is bad enough, dropping the rear DS, then manipulating the rear diff input shaft may yield movement, but that's only if it was close to "You were lucky to make it home..." status. A failed or failing bearing may not show up with that simple a test, which is where a good diff tech may come in handy, especially if you take a look at what's involved and compare your tool and skill sets to what's needed.

First things first though, gotta figure out if the pinion seal is the source.

 

[ChaseTruck]

If it smells like gear oil, it's probably gear oil... But once the truck is coated with fluid from whatever the leak is, it's just guesswork what it might be.

Power wash everything, let it dry, bring fluid levels to spec (as in: if the diff is dry, it probably won't leak...), dust everything with baby powder (aka cornstarch; wear a mask...), drive (keep it dry - no driving in the rain, no puddles), inspect...

Or declare any underbody hydrocarbon coating to be (extra) rust protection, keep fluid levels filled, and call it good.

 

[badmuthatrucka]

After landing on my rear DS on a trail, my pinion seal was shot. It looked a lot like your initial pictures after the three-hour drive home. Check the oil level, disconnect the rear of the shaft from the rear diff, and see how much play is in that pinion shaft. If it doesn't feel like there is any play, replace the seal and drive it around. If there is play, or if it starts leaking again, then more drastic measures are called for.

 

[Ryno80]

Just had another look.. there is definitely no play when pulling and pushing the shaft at the diff.. solid as.. but I suppose it would have to be proper loose for this to show..

Have got a couple of close pictures.. not sure whether the the edge of the piece joining the u-joint to the diff is supposed to be flush with the diff housing or a little out. The pictures below show mine to be a little out (maybe 2mm)








I have given it all a good clean but still can't get the darn filler bolt out.. ive tried penetrating spray, hammer, heating and cooling.. think its time to head down the hardware store and grab me a long breaker bar to torque this baby out.. will report back once done.
Cheers fellas!

 

[Ryno80]

Finally had some spare time last night to pop the filler bolt off and have a look at the level of diff oil in the rear diff. It is definitely quite low. As i understand it, the oil is supposed to be right below the filler cap, with mine, I wasn't able to see any oil to as far down as roughly 15mm from the filler cap. (was able to confirm this by using a small cable tie as dip stick).

Does this confirm the worn pinion seal theory?