Hi all! Newby here. Have 2000 miles on my 2004.5 LLY 2500HD CC and thought I would change the rear diff. lube. The owner's manual states that the proper fill level is from 0 to 1/2 inch below the filler plug hole. It took @ 4 quarts to get the lube level with the filler hole. I measured how much lube drained out from the factory fill and it was only @ 2 1/2 quarts. Did I way overfill or did the factory way underfill? Thanks! Great forum! http://dieselplace.com/forum/smileys/smiley20.gif

They have been known to come from the factory low.

Mine was the exact same way. I think GM is trying to save a buck or two on oil.http://www.dieselplace.com/forum/smileys/smiley18.gif

Low from factory! JJ http://www.dieselplace.com/forum/smileys/smiley4.gif

I have posted before the spec to fill the rear is only 3 qts.....Only on 04's

Check out this thread...

Rear Diff Oil Level Dispute (http://dieselplace.com/forum/forum_posts.asp?TID=11093&KW)

Thanks all for the responses. Looks like I need to drain a quart out. I apologize for not digging around for info on this topic before posting the question. http://dieselplace.com/forum/smileys/smiley9.gif In the future I will look for exisiting info on my questions before posting.

you will be fine leaving the extra fluid in it. I would prefer to have mine filled up to the hole rather then GM's spec.

I have posted before the spec to fill the rear is only 3 qts.....Only on 04's
Just for giggles, wonder what the spec for the 05's is. Did they keep the lower level or go back up?

Jim

I justed asked the same question on the "Rear Diff Level Dispute"
link. My '05 owners manual says proper level is the 0-1/2" from
top which was proven incorrect with the SI for the 04's???????

04 and 05 read the same for inspection procedure:




<LI ="1">


Inspect the lubricant level. Specification


The lubricant level should be between 17-21 mm (0.6-0.8 in) below the fill plug opening.
<LI ="1">If the level is low, add lubricant until the level is between 17-21 mm (0.6-0.8 in) below the fill plug opening. Use the proper fluid. Refer to fluid and lubricant recommedations in Maintenance and Lubrication. </LI>Edited by: dmaxalliTech

Thanks!

http://service.gm.com/servlets/CellHandler?CellId=53256&amp; (http://service.gm.com/servlets/CellHandler?CellId=53256&amp;RefDoc=1381049&amp;evc=sm) RefDoc=1381049&amp;evc=sm


Can't access that link. I am not authorized to view that.

Hi all! Newby here. Have 2000 miles on my
2004.5 LLY 2500HD CC and thought I would change the rear diff.
lube. The owner's manual states that the proper fill level is
from 0 to 1/2 inch below the filler plug hole. It took @ 4 quarts
to get the lube level with the filler hole. I measured how much
lube drained out from the factory fill and it was only @ 2 1/2
quarts. Did I way overfill or did the factory way
underfill? Thanks! Great forum! http://dieselplace.com/forum/smileys/smiley20.gifThat is exactly how mine was. I changed mine at 1000 miles, and put in 4qts of Mobil 1 Synthetic.