When doing the fluid change is there a way to tell if the level of oil in the differential is too low?
I have a humming in the rear end and i suspect it is low in fluid,but i personally have never been back there to look, car has 120k miles.

My eyes!!!

Just do a fluid change if you don't know when it was last done. Then you'll know for sure that it's filled to the correct level.

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'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

How much fluid do i need for the change? w116 1090 300SD, thanks.
Sorry i was playing with fonts and sizes, lol

I use as a rule of thumb, when I get the oil in the diff and starts overflowing through the filling hole, it's full. My only available dipstick is my index finger...

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[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT

anyone know the oil capacity down there? just so i know how much of that stuf to buy. Synthetic?

The manual specifies 1 liter (or until it runs out of the filler hole) of 85W90 or 90W hypoid gear oil.

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'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Make sure you are able to loosen the fill plug before you drain the differential. I was unable to loosen mine, and had to take it to my mechanic. If I had drained the fluid first, I would have been in a bind. He charged me $35 dollars for the job which was well worth it, saving me a lot of aggravation.

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96 E300d

I use about 1.3 quarts in the diffs I've worked on.
1 never seems to fill it.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

So diesel giant couldnt have filled his with just one quart of the Amsoil ha!!!
2 quarts im buying today, thanks Gang.

Filling an old differential with synthetic is only going to possibly cause leaks, plus you will gain no benefit from doing so.

To fill the proper amount of oil, the car must be on its wheels - not with the rear wheels hanging.

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Don't Chrome them; polish them

280 ex what brand would you recommend for my w116? and weight??
If rear is up in the air will it take a lot more fluid than needed?

Collect and measure what came out if you want to know if it was low. I couldn't get the fill plug to budge with a 1/2 " breaker bar and couldn't add a pipe for more leverage because the car was not high enough off the ground.. I supported the end of the breaker bar with blocks of wood and lowered the the jack to put the cars weight on it and it loosened.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

if the car is level, just fill til it runs out the fill hole. don't worry about over filling or anything just do it.

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1984 300TD "MAX" 303K+ still going...
fast '70 Chevelle 200k+
home built Shovelhead chopper

Are you guys using a pump to get the new fluid in? any suggestions on how to fill the diff??

I used a $3 syringe from Walmart. Took about 15 shots.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked