Rear diff fluid ???
 

Anyone know if it's necessary to change the rear differential fluid HOT or not warmed up? Is hot and often the rule here too?

aa

I would think its preferible to do so shortly after a drive......so that anything that would settle out is still in suspension when you drain it....

It doesn't require frequent changes but doing it sooner isn't going to hurt it any and may help extend its life even longer.

I am planning on doing mine tonight.....if my fill plug comes out..adn certainly if the drain plug coes out after that...


Thats important...remove the fill plug FIRST......becasue if you can't get that out you will have lost nothing....if you drained it first then you are in a world of hurt.


I'm using Mobil-1 syntetic gear lube.

I switched to Moble One diff oil.....what the heel at $7! Now I'm living large with 100% synthetic everything, even the brake fluid!:wacko:

I have Mobil 1 Syn in my rear diff too...as well as mobil 1 synth ATF, engine oil is still dino

Yeah, I can't emphasize that one enough.....one of the first projects I did on my 300cdt was a diff. fluid change; took out the drain plug, only to find that the fill plug was stuck..:(

After two hours, half a can of bolt break-free, and most of the skin on my hands, it still hadn't budged.

Lucky for me that I had an explorer on hand with some army surplus tow cables.....:D that sucker came RIGHT out!

although I wouldn't recommend that ;) , avoid it if possible

Well I got done with my K-1 kit install and new filter and fluid in the transmission, and my Differential oil change...

I got lucky..both my plugs came out fairly easy without any excessive effort on the differential.

Remember if you stick Mobil 1 in the diff you should change it again in a year. When I first did mine the fluid was probably original and came out looking real clean. Just for the heck of it I did it again a couple of months ago while the car was blocked up with the trans out. The one year old Mobil came out black as engine oil!:eek: People are not kidding when they say that stuff cleans!

I plan to....the stuff that came out looked pretty clean..........so maybe its been changed before...unlike the brake fluid, or the power steering fluid both of which looked like real strong coffee in color.

WWIII blues.....continued
 

"I'll let ya be in my dream
if I can be in yours'...
I said that."
"........Lit a cigarette on a parkin meter and walked on down the road."

The fill plug is typically in the aluminum cover. You can easily remove it by applying a bit of heat with a propane torch to the housing, outside the plug. Not a lot of heat.........just a bit to expand the housing away from the plug.

Needed tools?
 

What tools are needed/recommended for changing the diff fluid?

JWJ

14mm hex key. Get one that attaches to a socket so you can put it on your 24" breaker bar.

Its really easy to do if you work safe! Here is the procedure.

http://dieselgiant.com/mercedesreardifferentialfluid.htm

Use synthetic fluid if possible and do try to change is after the car has been run a while. The warmer the fluid is the better.

Not sure if it has been mentioned but make sure you clean in & around the drain & fill plugs so your 14 mm hex will seat in deep.

The last post is important. On a couple of plugs I wondered if the plug was going to release or a piece of the housing was going to come along with it as well. You want as much area on the tool to plug as you can get. Certainly not the dirt shoved ahead by the hex limiting the total available contact somewhat. Also always make sure the fit of the hex tool is pretty tight as rounding that nut out might not be funny. Although I have not heard of anyone accomplishing that yet. Place for a little anti seize as well perhaps?