Rear Diff Sludge!

[grahamnaismith]

Drained the front and rear diff today and front diff fine but the drain plug on the rear diff was coated with thick lumps of the dready muddy silvery almost mercury looking sludge with a few small bits of metal in there. Have done a fair bit of wading I suppose but do have raised breathers on them so a bit unexpected. Apart from that the oil itself looked fine.

So my question is what next? Driving to Petra in Jordan in 13 days (if Syria holds out) - what's the best and worse possibilities? How should I clean it out? Just refill it? Does it need dismantling to see what the damage is? Is this a Code Red?

Appreciate your thoughts guys

Graham

 

[Chris]

Worth jacking each side of the axle up to drain what's being stored in the arms. I find that there is quite a but that doesn't come out when the car is level. If it's a bit nasty, you don't want to ruin good new oil. I am guessing that a 100 axle is similar to an 80 in this respect.

Chris

 

[grahamnaismith]

Worth jacking each side of the axle up to drain what's being stored in the arms. I find that there is quite a but that doesn't come out when the car is level. If it's a bit nasty, you don't want to ruin good new oil. I am guessing that a 100 axle is similar to an 80 in this respect.

Chris

Top tip - like that!

 

[uHu]

Don't know about your rear axle, but Petra is the most beautiful place in the middle east. Magic colours.
Best time is at sunset with the full moon already up.

 

[Andrew Prince]

Drained the front and rear diff today and front diff fine but the drain plug on the rear diff was coated with thick lumps of the dready muddy silvery almost mercury looking sludge with a few small bits of metal in there. Have done a fair bit of wading I suppose but do have raised breathers on them so a bit unexpected. Apart from that the oil itself looked fine.

Hi Graham,
I think you'll be ok - if the oil looked fine, as you said, then no water has entered the diff/axle. The sludge on the drain plug is just metal particles captured by the magnet, which has done its job and removed the particles from the oil. Hard to judge from your description whether the amount of sludge is indicative of a problem or just normal wear & tear. Big chunks of metal would indicate breakage but tiny particles could/should just be normal wear & tear.

When was the diff oil last changed and any work done on the rear diff recently? If the diff oil was changed 5k miles ago and there was no metallic sludge on the plug at the time, then I'd say you have a problem. If the diff oil hasn't been changed in living memory, then what you've found sounds pretty normal. Also if the diff has been worked on recently, then the particles are likely to be the product from the diff bedding in.

Cheers,

 

[grahamnaismith]

Drained the front and rear diff today and front diff fine but the drain plug on the rear diff was coated with thick lumps of the dready muddy silvery almost mercury looking sludge with a few small bits of metal in there. Have done a fair bit of wading I suppose but do have raised breathers on them so a bit unexpected. Apart from that the oil itself looked fine.

Hi Graham,
I think you'll be ok - if the oil looked fine, as you said, then no water has entered the diff/axle. The sludge on the drain plug is just metal particles captured by the magnet, which has done its job and removed the particles from the oil. Hard to judge from your description whether the amount of sludge is indicative of a problem or just normal wear & tear. Big chunks of metal would indicate breakage but tiny particles could/should just be normal wear & tear.

When was the diff oil last changed and any work done on the rear diff recently? If the diff oil was changed 5k miles ago and there was no metallic sludge on the plug at the time, then I'd say you have a problem. If the diff oil hasn't been changed in living memory, then what you've found sounds pretty normal. Also if the diff has been worked on recently, then the particles are likely to be the product from the diff bedding in.

Cheers,

I hadn't done since I got it (2008)! Have kept it topped up but not emptied it. Had new actuator fitted and that's all. OK answer I wanted to - thanks Andrew.

 

[Julian Voelcker]

Graham, didn't we change an oil seal on one side of the axle a couple of years ago - just checked - September 2009?

I seem to recall the oil that came out was pretty mucky so wouldn't be surprised that there is some coming out.

Are you getting any whining from the rear axle on acceleration/deceleration?

 

[grahamnaismith]

Graham, didn't we change an oil seal on one side of the axle a couple of years ago - just checked - September 2009?

I seem to recall the oil that came out was pretty mucky so wouldn't be surprised that there is some coming out.

Are you getting any whining from the rear axle on acceleration/deceleration?

Good memory Mr V!!! Yes just checked as well - you did do that! You should do this car lark for a living I tell you! No symptoms of anything dodgy at all to be honest. Greg at Landcruisers Overland has been working on it and he didn't notice anything dodgy either. Thought I would risk it and can always drive home front WD as Greg suggests if it all goes to pot. Mind you, by the sounds of Syria, that will be the least of my worries!

So if, after 8k, I empty it in a month and it is all fine and clear and nothing on the sump plug, what conclusions, if any, can I draw?

 

[Andrew Prince]

So if, after 8k, I empty it in a month and it is all fine and clear and nothing on the sump plug, what conclusions, if any, can I draw?

If you've lost no oil and the diff is making no untoward noises, you can conclude that all is fine