Name this Leak - PeachParts Mercedes-Benz Forum

disqo · #1 03-23-2011, 03:49 PM

I was looking under the back of my TD yesterday and noticed the fuel tank and much of the right rear underside looked wet. Put it on ramps last night and could not really tell where the leak was coming from. This is the area under the cargo portion of the car with fuel lines sls lines and the differential. I wiped everything down real good and today when I look there is a drop coming off of the axle boot. When I squeeze the boot more fluid comes out. The leak is definitely not coming from above and the sls fluid is at a normal level. The differential fluid could be a tad low, but when I stick my pinky in the fill hole the level is just below the hole. The fluid leaking does not quite have the distinct smell that the gear oil in the differential has. So my big question would be is there fluid in the axle boot itself that is leaking out, or is this differential fluid that is getting past the seal and leaking from the axle boot. The left and right axles on the car do not look the same. I am guessing that at least one of them was replaced sometime in the past. Any help is appreciated.
Thanks!

Shane

Stretch · #2 03-23-2011, 04:00 PM

How do the axle boot feel - do they feel like they are full of oil?

disqo · #3 03-23-2011, 04:23 PM

After squeezing the boot, a pretty good bit of oil continued to come out. It seems pretty full. As soon as I wipe it off another droplet forms.

79Mercy · #4 03-23-2011, 04:25 PM

reboot or replace your axles. I have heard the VStech is a great person to get rebuilt axles from here on the forums.

disqo · #5 03-23-2011, 04:27 PM

So do you think the problem is with the axle and not the diff?
Thanks,

Shane

Aquaticedge · #6 03-23-2011, 04:47 PM

if it's forming on the boot then It's most likely the boot itself, I second Vstech, he may have some booted axles and I can vouch for his parts, they come very nicely packed and great prices

Biodiesel300TD · #7 03-23-2011, 04:49 PM

The CV joints have thick grease in them not drippy liquid. I'm not convinced it's the boots leaking. In my experience when the boots tear they leave a line of thick goo stuck to everything in the plane of the tear in the boot. If it really is dripping then there has to bee a good tear or cracking that you'd see visually by moving around the boot around.

I think it's a fuel or leak. Either a hose, or a steel line that has been rubbed through.

disqo · #8 03-23-2011, 05:33 PM

Mine is definitely a drippy liquid, but it does not smell like diesel either. After I wiped everything down last night, everything above the boot remained dry, but the liquid drips from the boot itself.

pwjeep · #9 03-23-2011, 06:29 PM

Unless you have personally rebooted your axles and you know what kind of lube you put in them... you may have any of the following types of lubes in the axles: Grease (from little packets) 75 / 90 weight gear oil (like you use in the differential... synthetic or not) or nothing (total loss of fluid). If it smells like differential fluid, then it probably is. If during the life of the car only some of the boots have been changed, you may have one or all of the above in the axles.

Could there be a leak from the differential... Maybe, but not likely. You'd have to open the fill plug on the diff. and stick your finger in to see if there's fluid in there or not. We could all probably benefit from a differential fluid change to a synthetic. When was the last time it was changed?

Another issue may be that the boot clips could have failed (they are loose).

Pete

vstech · #10 03-23-2011, 09:54 PM

Quote:

Originally Posted by Biodiesel300TD

The CV joints have thick grease in them not drippy liquid. I'm not convinced it's the boots leaking. In my experience when the boots tear they leave a line of thick goo stuck to everything in the plane of the tear in the boot. If it really is dripping then there has to bee a good tear or cracking that you'd see visually by moving around the boot around.

I think it's a fuel or leak. Either a hose, or a steel line that has been rubbed through.

Thanks everybody for the recommendations! I try my best to always be top quality in everything I do!
the pictured axles are original MB axles, definitely filled with gear oil from the factory! yours still have oil in them, they are prime to pull and replace the boots! I'll happily rent you the boot gun and get the right boots ordered for you, or send you cleaned and rebooted they are not hard to change and reboot. yours look quite clean, so should be no problem.
the diff oil is the same as the boot oil, but the two are not mixed, so diff oil can't leak from the axle joint.
to change the axles, you will need to drop the diff, drain the fluid, open the rear cover, and pull the clips off the axle ends. it's a good idea to change both axles, as the rubber will be the same age on both sides... (likely the same axles that came with the car)

disqo · #11 03-24-2011, 08:10 AM

Hey John,
How much to rent your boot gun and to get the proper boots from you? The car is my daily driver. I know it is hypothetical, but how long can I drive it as is before I do damage to the axles? I appreciate the advise and help!
Thanks,

Shane

vstech · #12 03-24-2011, 08:43 AM

Boots are about 34.00 each axle, and the Flexx gun is in the tool rental forum. contact me by PM for details etc...
you will also need a pair of crimp ring pliers. I have a set also.

Stretch · #13 03-24-2011, 09:22 AM

Quote:

Originally Posted by disqo

Hey John,
How much to rent your boot gun and to get the proper boots from you? The car is my daily driver. I know it is hypothetical, but how long can I drive it as is before I do damage to the axles? I appreciate the advise and help!
Thanks,

Shane

If you run them without oil you will damage them. You are way better off taking the bus for now - replacing the axles with cheap far eastern ones is frequently reported here as a big mistake. Generally the advice on this forum is to reboot an original axle instead of replacing with cheapo ones...