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Low Rear End Fluid!

tpseabird

Full Member
Joined
Oct 5, 2002
Messages
188
Location
U.S. Coast Guard
Today, I decide to take my 2003 AV to Xpress lube to have the fluids checked and the oil changed. I guess I'm a bit neurotic. My AV has only 577 miles, however, my last chevy purchase (2002 Trailblazer) was three quarts short on oil upon delivery. Besides, fresh oil can't hurt.

Anyway, when Xpress lube checked my AV rear end, it was extremely low on fluid. In fact, the tech said it looked dry. It took almost 3/4 of a quart to fill it to the recommended level. The rear end on the 2003 only holds 1.5 quarts. It was half full...not good! :6:

My AV is running great and (knock on wood) hasn't had any problems. My advice to any new owners is to check your fluids. This was the second time fluid levels were delivered low!

Maybe this was a precursor to the rear end problems some Av owners have stumbled upon...

Todd
 
Being low on fluid could play troublesome on the rear especially a locking rear-end with the eaton unit. Good call on having them check the fluids, for this could be a normal practice to only fill half way. Glad you posted this, for I am going to check mine later today just in case.
 
Glad you posted this, for I am going to check mine later today just in case

F.Y.I.

I let the dealer know about the low fluid and they told me the fluid should be .6 inches from the bottom edge of the fill hole.

TP
 
If I remember correctly, low rear-end fluid is a TSB item on early 2002 models - seems the folks in Mexico haven't learned much on this issue...
 
Anyone have a pic on where the fill hole is and how to check it or can you give good directions. I want to check it, but don't want to take it to the dealer and I don't want to mess anything up. Also, if it appears low, should I do the fill or take it to the dealer and then let them know it's low? Thanks.
 
PUREAV said:
Anyone have a pic on where the fill hole is and how to check it or can you give good directions. ?I want to check it, but don't want to take it to the dealer and I ?don't want to mess anything up. ?Also, if it appears low, should I do the fill or take it to the dealer and then let them know it's low? ?Thanks.

The fill hole is on the right front side of the rear differential. If it is low, make sure you use the right stuff. I believe it calls for SAE 75w 90 synthetic. Just check your owners manual. The Chevy dealer charges $29.00 a quart for this oil; however, I'm sure the local parts store has some for a lot cheaper!


TP
 
tpseabird said:
Anyway, when Xpress lube checked my AV rear end, it was extremely low on fluid. In fact, the tech said it looked dry. It took almost 3/4 of a quart to fill it to the recommended level. The rear end on the 2003 only holds 1.5 quarts. It was half full...not good! ?:6:

Todd

Todd,

You need to take your AV to the dealer and have the fluid level rechecked ASAP. ?I had this same thing happen to my Suburban and you will not beleive what Xpress lube was doing.... :7: ?To increase sales they were over filling the fluids. ?I was concerned just as you so I went to My local dealer for a recheck. ?Yep overfulled and the tech indicated that it could have blown a seal if not caught. ?Do not trust these fast lube centers!
 
B&M makes a syn 75-90 gear oil. It sells for $7.00 a quart in HI at the local discount auto parts store. I bought some for my son's Jeep M/T. I did not verify what weight the AV uses in the rear end.
 
You need to take your AV to the dealer and have the fluid level rechecked ASAP

After I left Xpress lube I went straight to the dealer. I told them the story and they checked things out for me. A GM certified mechanic at the dealer said the level was perfect. I got lucky!

TP
 
What a kawingkydink
I did my 2002 Z71 on thurs
with vehicle on flat level surface and after sitting a 1/2 hr
both the front and rear diffs took over a pint each I called a friend who who works at a dealer and he said many have come in low
With all the post popping up about rotational noises, its no wonder things are failing
 
:7:From the sound of these problems it sounds like the auto techs are sitting in the coffe break room filling out the new car inspections.
I got to look at the truck when i bought it and they were doing the delivery checklist. That was one of the items they checked,,, go figure, maybe they were aware of it happening before..
Glad you brought it up though to make everyone aware, does not take 3 minutes to check it. I think it still takes a 3/8ths ratchet head to fit in the square hole and back it out. Mechanic said you should be able to stick your little finger in and just fill the oil right at the edge of the hole. if you have big hands you may need assistance ;D
zeeya
 
:7: Hey, thanks guys. I have a 2002 AV and after just breifly running across a post here about low fluid in the rear's I checked mine.

I open the fill hole and stuck me little finger in and down as far as possible, guess what, no oil. So I then opened the drain plug and let a little drain into a cup. It was MUD! There are LOTS of metal shaving in the oil which is probably normal when breaking in the new gears. This definetly warrants a rear fluid change after just 500 miles as I read in the Edmunds web site. Unfortunatily I now have 4000 miles and just discovered this. I do get a slight clunk towards the rear when accelerating on a slight down slope. Could this be due to low oil and wear in my rear end?!? It's possible.

Never the less, its going into GM service today and I'm having them replace the fluid, and check the fluid in the front diff as I did not check that.

JUST A NOTE: The book say that the read Diff oil should be 5/8 inch to 1-5/8 inch BELOW the bottom of the filler hole for the REAR and 1/2 from bottom for the front DIFF, so reaching the rear with your finger is tough. Need to use a bent paper clip or something to reach down in the case.

Never the less, I believe that my little finger got down at least 5/8" in the rear case. And yuck, the slop that came out of the drain was more than enough for me to have all the fluid changed.

My advice, check ALL the fluids when new, and have the DIFF fluids REPLACED (and not just checked) at 500 miles!!!

Black mud with metal shavings in my rear, no thanks!
 
Well people I thought I had the same problem back in july. My rear differential was what I thought to be real low. I have never had a vehicle in the past where the oil level in the axle was supposed to be that low. But according to the owners manual :
"Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. The proper level for the 1500 Series is from 5/8 inch to1 5/8 inch (15 rnm to 40 mm) below the bottom ofthe filler plug hole. The proper level for the 2500 Seriesis from 0 to 112 inch (0 to 13 mm) below the bottomof the filler plug hole. Add only enough fluid to reach the proper level"

So what did I do? well I added oil thinking it was low . Then I kept thinking surely the general would not do this to me(yea right). So I looked in the manual and discovered that the level was within specs to start with on the lower end of the spectrun though. So now the fun begins drain out enough oil to get it right.
So I got the level right so all is well.

Happy AVing to all
 
My 02 Z-66 has a blue tag just above the fill hole that tells you what to put in and to what level. My old 99 silverado came from dealer 1 quart down I found that at 4,000 miles. Ex-dealer then added 1 quart of 80W90 gear oil paying no attention to the blue tag that tells you to use only synthetic 75W95 he says makes no difference. I said do it right, drain it out and refill with proper fluid. I found a chevy dealer 25 miles further away that keeps me happy. Besides I really like driving my Av (y) (y)
 
I have not owned a rear-wheel vehicle in many years, and I have never owned a 4WD truck. Therefore I have no experience in differentials.

I have been having all my vehicles serviced at the local Monro for several years and know the manager pretty well. I am curious if they have been checking the differential fluid levels during oil changes without being instructed to do so. My guess is no since it has never been mentioned.
 
After reading this post..I'm concerned...about checking my level as well...up till now I've just done the oil changes, chassis lubes, tire rotation, but never paid attention to the rear.....at 14,000 and change I didn't think this was going to be an issue....

I'm due in for service next week and I'm going to ask them to check the levels in the rear....or should I just have them change it while I'm there to get rid of the "break in" shavings....I don't want them to look at me like I have 3 heads....but I wouldn't want to gamble with my Avy either... :B:
 
Yes irontrain....I know what you mean...better safe than sorry .....next week I'm taking it in and let them check it out.... :B:
 
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