Front Differential Leak (1 Viewer)

Joined
Jul 14, 2020
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Location
houston texas
I bought a 2003 LC about 18 months ago from a dealer in Ft Worth Tx. I gave it a once over looking for leaks under the vehicle and it was dry etc. it drove well back from Ft Worth to Houston but seemed like allot of heat coming from the front end. Anyway I dont drive it much and decided to have some maintenance done. Changing the diff and transfer case fluids. I decided to do it myself since the dealer wanter about $200 per gearbox to do it. Everything looked good, the rear diff fluid looked relatively new the transfer case darker. When I got to the front diff the top plug was a torx and was very tight. I got it off and it looked like someone tried to jam a hex in there. When I removed the drain , the plug had this gelatenous black sludge attached. Nothing was draining out so I stuck my finger in and more sludge came out and finally a little fluid but not much. I filled it with M1 75/90 and the leaks began. I am monitoring it but it seems to be losing an ounce a day. It doesn't seem to be leaking from the plugs but strangley above the fill plug. I believe the reason I saw no leaks when I bought it was because it had very little fluid in it. Any advice appreciated, after reading some posts on the subject seems like a seal. Any Idea on the cost of replacement? I thought about putting in a thicker oil 80w140 but it leaks just parked.
 

2020 Rocks

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Your seal on the front diff cover could be bad. If your diff breather is clogged, as pressure and heat build up, the diff fluid will be forced out of the weakest point. You may need to remove the entire diff to overhaul it, with such a low sludge level of fluid, I personally would be looking into replacing the diff with a good salvaged unit. GL!
 
Joined
Mar 25, 2019
Messages
846
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NWFL
hmmm, this seems weird. The sludge definitely doesn't sound good, probably did run low on fluid. I'm surprised the truck made it as far as it did, but I would probably want it checked or replaced before doing any longer trips, the bearings in there are probably shot.

I had a front diff leak a couple months ago and I had to replace my oil seal. Not really that hard honestly, but make sure you seat the seal correctly. There are some good threads on it here.

The cost for the seal was about $60 for me and about 2.5 hours in the driveway. That included new fluid and a seal puller tool I had to buy ( definitely buy that) Maybe try replacing the fluid and seal and see what happens? The LC build quality is surprising sometimes, maybe the bearings in the diff are still good.
 
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Joined
Jul 14, 2020
Messages
2
Location
houston texas
Thanks for the replies. I'm monitoring the leak for volume. I will use this change as a flush to see what comes out when I get back under it and drain the diff and replace the drain/fill plugs. I will also be looking for the source taking pictures. Since I'm 67 I have started to realize I cannot do the things I did at one time. I had bought all the parts to do the timing belt and water pump but faced reality when I hurt my back. I have always done most of my own work since I had my first vehicle because initially it was economics and later its that I know what has been done and done correctly.
 

ramangain

Clarksonian disciple
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Feb 6, 2020
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Atlantis - recently discovered in the Rust Belt
I'm a bit shocked that the box and gearing survived a lack of lubrication so far. I can't see how leaving any sludge in there would be a good idea either.

Are there any products which can be pumped through under pressure to break down and flush the sludge out without:

- damaging the internals and seals
- removing the housing from the truck

?
 

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