: Over-filling differential/capacity of differential?



fre1102
03-04-13, 04:26 PM
So I just swapped the diff. fluid in my car (2006). The FAQ says two quarts plus four ounces. I got about 1 3/4 quarts in it before it starting starting shooting out of the fill port. I was going slow, I let all the air get out, and when I pulled out the line, it gushed out, and kept coming out for several minutes.

The car's level, and I let it drain.

What am I missing here? And is there something wrong with over-filling the diff.? I've never heard of anything bad happening with over-filling a differential, but I'm scared of a V diff. in general, so I want to take care of it.

tommy compton
03-04-13, 06:17 PM
Probably wouldn't do any thing but make a mess when it spews out the vent.
Just let it drain (out of the fill hole) untill it no longer comes out the fill hole.

NCOGNITO
03-04-13, 07:00 PM
Probably wouldn't do any thing but make a mess when it spews out the vent.
Just let it drain (out of the fill hole) untill it no longer comes out the fill hole.

This is correct, the PO did me a "favor" of changing the diff fluid before I bought my V and after 200 highway miles I noticed that I had a nice coating of gear oil all over the bottom of the car behind the diff, spare tire well, back bumper and trunk. Other than scaring the crap out of me, no real harm done.

silentwig
03-04-13, 07:16 PM
This is correct, the PO did me a "favor" of changing the diff fluid before I bought my V and after 200 highway miles I noticed that I had a nice coating of gear oil all over the bottom of the car behind the diff, spare tire well, back bumper and trunk. Other than scaring the crap out of me, no real harm done.
Thats what Im talking about. Good old fashion corrosion inhibitor. :cool2:

fre1102
03-04-13, 07:16 PM
Good deal, that was my approach. Thanks guys.

rand49er
03-04-13, 10:12 PM
So I just swapped the diff. fluid in my car (2006). The FAQ says two quarts plus four ounces. I got about 1 3/4 quarts in it before it starting starting shooting out of the fill port. I was going slow, I let all the air get out, and when I pulled out the line, it gushed out, and kept coming out for several minutes.

The car's level, and I let it drain.

What am I missing here? And is there something wrong with over-filling the diff.? I've never heard of anything bad happening with over-filling a differential, but I'm scared of a V diff. in general, so I want to take care of it.I put 44 fl oz the first time I did it and 42 the second time. If the FAQ says "two quarts plus four ounces," then it's wrong.

fre1102
03-04-13, 10:16 PM
Hm. That's a lot closer to what I got into it. Looking more at the bottle and accounting for what's now on the ground, I'd say there's less than 1.5 quarts in the diff. itself.

CTSV_Rob
03-05-13, 12:32 PM
I put 44 fl oz the first time I did it and 42 the second time. If the FAQ says "two quarts plus four ounces," then it's wrong.
I looked at the Amsoil website and it says 2.7 pints which works out to 43.2 ounces. Looks like they are pretty close to what you put in rand.

There is no way you will fit over 2 quarts in that diff.

They have a decent site for fluids and filters:
http://www.amsoil.com/mygarage/VehicleLookupPage.aspx?FromIndex=1&url2=2007+CADILLAC+CTS+V

Andringa
03-05-13, 03:02 PM
Regardless of the amount you put in, it should be filled up to the fill hole. So you should be perfect.

Naf
03-06-13, 12:39 AM
After you fill it the first time, take it for a small drive, get the trapped air out of the diff and check the level again.

I have the trans cooler so checking the level isnt the easiest thing in the world

silentwig
03-07-13, 12:51 PM
After you fill it the first time, take it for a small drive, get the trapped air out of the diff and check the level again.

I have the trans cooler so checking the level isnt the easiest thing in the world
Trapped air out of the diff? Most diffs are vented including ours correct.

Andringa
03-08-13, 09:56 AM
Trapped air out of the diff? Most diffs are vented including ours correct.

Yes, ours is vented.

What he meant was that there could be air trapped down in the diff oil, which would make it appear fuller than it really is. Just a precaution against under filling.