How Much Gear Oil (qts) Is Need To Change.

blkmonster03 · May 8, 2008

I was reading the owners manual, and trying to find how much of gear oil do I need. Well, sure enough the manual only gives me the type and weight i should be using. Can anyone help me? I plan on using synthetic, the aka (purple stuff) 75w90 i believe was what was recommended. Also, by all means i'm open for any recommendations.

Schmids5.3l · May 8, 2008

I got 3 jugs of Royal Purple and filled until it started flowing out of the cap. Put the cap on and called it a day. I got well into the 3rd one if I remember correctly.

Alljackedup408 · May 8, 2008

whats the vehicles info?? give me year and specs... ill look it up on GM SI.. im a service tech and can get the info for you.

blkmonster03 · May 9, 2008

whats the vehicles info?? give me year and specs... ill look it up on GM SI.. im a service tech and can get the info for you.

Thanks for all the replies. My info: 2003 Silverado LS ext cab, 5.3L 4wd, no auto trac.

Alljackedup408 · May 9, 2008

GM recommends - SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 12378261, in Canada 10953455) or equivalent meeting GM Specification 9986115. And as far as ammount ,,, which ever rear end you have.. these are the specs... so its safe to bet buy 3 quarts.. and just fill til it starts to run out..

Rear Drive Axle (8.6")

2.03 liters

2.15 quarts

Rear Drive Axle (9.5")

2.6 liters

2.75 quarts

Rear Drive Axle (9.75")

2.84 liters

3.00 quarts

Rear Drive Axle (10.5")

2.6 liters

2.75 quarts

Rear Drive Axle (11.5")

3.62 liters

3.83 quarts

bobf1234 · May 9, 2008

I got 3 jugs of Royal Purple and filled until it started flowing out of the cap. Put the cap on and called it a day. I got well into the 3rd one if I remember correctly.

I think you might be way over-filled... If I remember correctly the fluid is supposed to be somewhere between .5 - 1.5 inches below the fill cap.

pennzoil29 · May 9, 2008

I got 3 jugs of Royal Purple and filled until it started flowing out of the cap. Put the cap on and called it a day. I got well into the 3rd one if I remember correctly.

I think you might be way over-filled... If I remember correctly the fluid is supposed to be somewhere between .5 - 1.5 inches below the fill cap.

I think mine took about 3 qts. I've alway's been told to fill it until it trickles out of the fill hole. I don't think he's over full.

C & A s Dad · May 9, 2008

I got 3 jugs of Royal Purple and filled until it started flowing out of the cap. Put the cap on and called it a day. I got well into the 3rd one if I remember correctly.

I think you might be way over-filled... If I remember correctly the fluid is supposed to be somewhere between .5 - 1.5 inches below the fill cap.

Adam is correct here. The fluid level should be apprx 5/8" below the bottom of the fill hole. This is one of those cases where more is not better. This level, which is recommended by the OE mfg takes into to consideration the rear wheel bearing and seal area. Too much could cause a leak issue in this area. This is not likely to happen but why not follow the instructions of the Mfg.

Schmids5.3l · May 9, 2008

According to

* Rear Drive Axle (9.5")
2.6 liters

2.75 quarts

I put in just enough, about half way thru the 3rd bottle. I think it'll be fine, changed the fluid about a year ago, so far so good.

I think you might be way over-filled... If I remember correctly the fluid is supposed to be somewhere between .5 - 1.5 inches below the fill cap.

I'm not sure how your supposed to know when it's 1.5 inches below the fill cap. If I remember correctly I couldn't get very far in there with my index finger.

bobf1234 · May 10, 2008

I think you might be way over-filled... If I remember correctly the fluid is supposed to be somewhere between .5 - 1.5 inches below the fill cap.

I'm not sure how your supposed to know when it's 1.5 inches below the fill cap. If I remember correctly I couldn't get very far in there with my index finger.

Use a metal coat hanger, make it about 4 inches long and bend it at 90 in the middle. Just past the threads in the fill hole there is a small hole on the bottom, you should be able to get that coat hanger through the hole.

C & A s Dad · May 11, 2008

I used a plastic cable tie. Bend it 90 degrees 5/8" from the end and stick the bent piece in the hole. Fill it until it begins showing gear oil on the tip of the cable tie.

bobf1234 · May 11, 2008

I used a plastic cable tie. Bend it 90 degrees 5/8" from the end and stick the bent piece in the hole. Fill it until it begins showing gear oil on the tip of the cable tie.

Even better haha, a lot easier than my way.