Rear Axle!!

[David Proske]

After reading some posts on the TDR forum about Dodge selling new trucks with no rear axle fluid I thought I would take a look

[sonofagun]

David,

The rear differential takes a bit over 4 qts of oil. If they got 1.5 qts in you were about 37% low. If you didn't hot rod it and given the fact that it is cooler here in Texas this time of year and you haven't towed anything you are probably ok. I would go back and have the service MANAGER add a note to the work order about the low oil from the factory issue. I would tell him you want a drain and refill so the old OVERWORKED oil is outa there. (Stick you finger in the oil and smell it before they drain it. If it smells burnt get a lot tougher). Ask them to pull the cover and check it out when they replace the gear oil.

Good luck,
Bob

[EWC]

When I worked at a Chevy dealer , we had to PDI ( pre delivery inspection ) the new cars . There was a checklist that you had to include in the paperwork . You had to sign and mark off on the list of items you checked . That paper should be in with all the other paperwork you got from the purchase . I'd take it back and make them check it again as they already missed the rear . What else did they miss ? Granted this was 10+ years ago but you still have to check the new cars out . Good luck .

[56Nomad]

David,

Just curious.... where was your truck built?

[SPICER]

I just checked all of my diff. fluids and found my rear axle low also. I couldn't tell how low, so I started adding. I used 1 full qt. and still did not have it spilling out. I could stick my finger in and feel the level right at the top.

These pigs take 4 qts.? They look like they take more like 10 qts.! Fill me in.....

And, my manual says nothing about ever replacing this rear fluid, only checking and adding. Any Suggestions? Is there an internal magnet that should be cleaned or is it OK to just drain and refill?

Also, I checked my front diff. and it is low also. It takes80w90, not the 75w90 synthetic. However I read on another post that part #12479296 could be purchased and installed on the front in order to make it synthetic compatible. It is a white plastic vent cover which replaces the black stock vent cover. Anyone else know about this. I bought one and it is white, $20 at the dealer. Not installed yet....Later. SPICER

[dmaxalliTech]

sounds as if some pdi's are slipping through the cracks. As noted above, all of them should be completely inspected. I would take a trip back to the dealer and let them check it, if its low, I would politly demand a reason why. Front diff can hold synthetic as long as new vent is installed. white vent has a metal deflector inside versus a plastic one on the black, also the oring to seal it is different. I use a thin bead of sealer when installing to prevent it from comming loose and leaking, we are seeing that quite a bit

[Joe P]

dave go to gm trucks .com they show how to ck.fluid using an allen key,also tell you how to change fluid. you should change that rear fluid asap even moreso if you have done any towing. When i changed the fluid i think around 1000 miles after two short tows,the fluid was black and had alot of fuzzies on the drain plug.

[David Proske]

Thanks for the reply's guys.

Nomad, looks like my truck was put together in Pontiac,MI.

When you guys changed your fluid, did you use the expensixe OEM stuff or another synthetic? I have been using Royal Purple 75-90 synthetic in my 94 with great results.

[SPICER]

dmaxalliTech,

any answers to my previous post? Also, what type of sealer do I use on that front diff.? SPICER

[Seattle Steve]

Awhile ago, there were several posts on this topic. The owner's manual says not to tow during the 1st 500 miles and then change the fluid if you have the G80 locker. This is because of high temps generated by the tight gearset during break in. Folks who have changed the fluid unanimously report terrible looking fluid and many also report fuzzies or even metal chips on the magnetic plug. One guy removed the rear cover and reported all was clean and no magnet found inside. Most here agree to use any 75W-90 synthetic rated GL-5 and many prefer the Mobile One product. I hope this helps.

[Nixter]

I see that GM specs 80W-90 for the front diff, and 75W-90 for my rear G80 locker. I was planning to use Mobil 1 synthetic 75W-90 in both. Does anyone find this objectionable and why? Perhaps this would be a good question for Dr. Lee.--Nick

[Jelisfc]

I checked mine tonight. Both axles and the T case were an inch low. ZF was over but the trans was still warm so I'll check it again when cold. We'll see what the dealer says tomorrow. Being in MN I'm going to try for them to warrant a front axle change to synthetic.

[huntindog]

Seattle Steve
I have asked this question many times in the past and have never recieved a response.
You seem to be knowledgable, so maybe you can tell me.
What page in the owners manuel does it state the differential fluid change intervals?
I have looked several times without finding it.

[oyazi]

Just thinking that the initial fill at the factory may be correct but some of the lube finds its resting place in the axle tubes/hubs? Isn't that why there is a PDI at the dealer? Could also be something to consider when changing fluids to make sure all of old stuff comes out.

[ 04-03-2003: Message edited by: oyazi ]</p>

[Maverick]

Nixter,
I have been running Amsoil 75w-90 in my 01' dually most of it life. Got 120K on so far with no problems. My 2500HD just went in for repair for front pinion bearings at 50K with the 80w oil. I would change it before next winter for sure. Read this thread.

http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=7&t=004822&p=

[Flyboy]

If I remember correctly, the G80 uses 3.8qts. You do not fill until it runs out the hole. I'm not real shure about the amount, but I think that's what the tech computer stated.

[peachin]

I checked my 2003 rear end at 2000 miles (200 hauling) It had the proper level. If I drain it at 500 miles towing - WHAT KIND OF TOOL do you use on the bottom drain plug?

Thanks peachin@msn.com

[Seattle Steve]

To all- My apologies, the owner's manual for my '03 GMC 2500HD does NOT state an interval to change the rear axle fluid, just checking it at 7500 mile intervals.

Huntindog- After a little checking, I dug up the info I remembered which is reported to be from the component manufacturer, Eaton. There is a recommendation for the 500 mile change and again at 50,000's if you tow heavy. Refer to

http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=7&t=002814&p=

for the story. I changed mine at 500 miles and it looked nasty. I have changed again at 1500 and 5000 and it is looking better each time. It is easy to do yourself and only about $30 for name brand GL-5 synthetic. It takes 3.83 quarts according to the Helms manual and my experience agrees with that. By the way, the Helms service manual does not offer any differing info on the maintenance schedule than the owner's manual.

Love your handle! I have an English Setter and a Lab/Brittany mix that I use on upland birds.

Peachin- Use your 3/8 socket wrench or extension without a socket on it for that bottom drain plug.

[ 04-03-2003: Message edited by: Seattle Steve ]</p>

[Dave]

I'm pretty sure I read in my 2001 manual that you should not tow for first 500 miles to allow the ring an pinion to seat properly. After 500 miles towing change the rear diff fluid. That is what I did. The fluid that cam out was a nasty grey and stunk. There was metal on the drain plug, real fine and powderie. Now the fluid, Amsoil in it has 70,000 miles on it and looks better than that first and only change at just over 1000 total miles. And yes, my 01 was delivered 1 quart low of diff fluid but It only had 25 miles on it when I filled it.

[JimWilson]

Trucks with either the dmax or 8100 use 3.8 quarts, while the 6000 uses 2.8 quarts. I swapped it out at 3K and it sure smelled foul. I used Amsoil in the front and rear.

[huntindog]

Seattle Steve
That's what I thought.
The reason I wanted to clear this up, is thhere have been MANY posts on which fluid to use in order to keep the warranty intact.
The answer is clear,,,, If warranty is the only concern,, then don't change it at all. Since GM doesn't recommend changing it under ANY conditions, then they could not deny a warranty claim on that issue.
If you change it, and don't use a fluid that meets GMs specs, then a warranty claim can be denied.
Personally, I have yet to do mine.
I have changed my other vehicles on a yearly basis for the last 18 years, and have yet to see any benefit from it. The fluid ALWAYS smells burn't, theres always metal on the magnet, and the rear ends wear out about the same as others that never change the fluid.
I think the metal on the magnet is no big deal, as the rear ends have no filter. I bet our motors shed a bunch of metal too, but we never see it as it's in the filter.

About my handle I have a Brittany named Rusty, she is currently the points leader in the Arizona Pointing Dog club. To see her record go here http://www.azpdc.org/gundog.htm

[ 04-05-2003: Message edited by: huntindog ]

[ 04-05-2003: Message edited by: huntindog ]</p>

[SPICER]

Quick Question.....

I am changing the fluid on my rear diff. The drain plug is pretty short and BARELY magnetized.
It certainly is not magnetized enough to pick up a nail. I am wondering if the magnet was glued to the plug and fell off? I can stick my finger in the drain hole and feel the gears very near the bottom of the diff. housing, so the plug needs to be short. I did have a very fine, minimal amount of metal dust on the plug, but again, MINIMALLY magnetic. Any Help? :confused:

[Fathead]

When I changed out my rear end fluid at twelve hundred miles the plug was holding a gob of metal which was paste like in it's consistency.The quantity was about the same as I have seen on other vehicles during fluid changes. The plug seemed to be well magnetized and doing it's job. I did not see anything that looked like a glued on magnet.
FH&gt; smile.gif

[jbplock]

I took some pictures of my front and rear diff drain plugs when changing the fluids at 5kmi. The front had a big glob of stuff that had grease like consistency. The rear had some metal and sludge. The fluid color was blackish gray and had the characteristic gear oil sulfur smell. See pictures at the following link:

http://community.webshots.com/album/65684589edLUNA
smile.gif

[SPICER]

I just finished the front and rear. I'm still not sure about the rear drain plug. The magnet was very weak, more like magnetized metal than a magnet. I will go to the dealer and ask to see a new one. My 1500 rear diff. had a magnet in the shape of a donut. It was glued to the cover. I had to take the cover off to change the fluid. When I did it had fallen off the cover and was at the bottom of the housing.

I found a trick when changing the front and rear. Let it drain for an hour or so and then use an air compressor. Wrap the air tip with a rubber glove to make a tight seal at the fill hole. Blow air all around inside the diff. and watch quite a bit of extra fluid roll out. Later.....SPICER

[jbplock]

Spicer,

My magnet was relatively weak too.

[SPICER]

jbplock,

Thanks for the pictures and the reply. It is interesting how weak the magnet is. My front magnet was much stronger and had more junk stuck to it, though one would think the rear would have more junk. I did notice that the gears are just above the drain hole. A taller/stronger magnet would probably not fit, and maybe the fast turning gears above the magnet acts to de-magnetize it a little? No biggy, thanks for your help...SPICER

[dmaxalliTech]

Not to keep on the type of lube subject, But I have a written 250k mile warrenty on both of my diffs. I drained out the factory lube and installed BG Products GL-5 75-90 front and rear. Rep gave me a warrenty and all I had to do was supply him with samples of drained fluid. I to had the gobs of sludge front and rear. The rear diff was very black compared to the front. I have serviced three trucks including my own at these low miles (less then 10k) and all have been the same color. I think if the magnet was stronger on the plug, it would act as resistance on the rear gear set, increasing fuel consumption. I think magnet is tuned for max efficiency :D :D

PS, I never have to touch my diffs again as far as changing oil, per BG, To keep my warr.

[technician]

To All,

I did not change my rear diff at all (per manual) and at 21000 mi. my locker started to chatter and grab. I took it to the dealer and they stated that the rear diff is to be changed out after break in. I replied that the manual said nothing about changing just checking. They replied that a manual is a guide ang can't have everything in it. :rolleyes: $127.50 later everything was OK :(

MORAL: Change diff after break in (at your first oil change :D :D

On edit: My locker seems to take longer to lock (more spin) than I think it should. Maybe I glazed the clutchs (cone)???

[ 04-09-2003: Message edited by: technician ]</p>

[huntindog]

technician
I have a 73 Blazer that I purchased new.
The diff. fluid has been changed annually since new. The first gears wore out at 162000.
Interestly enough, the manuel for this vehicle says to change the fluid every 12000 or annually whichever comes first.
This manuel is about 1/4 as thick as the 2001s silverado (not even counting the diesel supplement). The difference (I believe) is synthetic fluid.
It would take no extra room in the manuel, or extra effort to state a change interval, if one was required. They already address checking the fluid level at 7500.


The moral,,,, You got ripped off. Go back and demand a refund.

[JimWilson]

Hey technician; I agree with huntingdog -- you got ripped. The amount of "room" it would take in the manual to tell you when the diff fluid needed to be changed is not more then a sentence, so what your dealers (stealers?) service rep said is a bunch of horsesh!t.

FWIW... Since I have the 6.0 I only needed 3 quarts to refill mine. At $7 per for Amsoil it cost me $21 and about an hour of time (only because I let the diff drain for almost an hour to make sure it was all out). I'd be telling that dealer to refund my money pronto because that was a warranty repair.

[technician]

Suuurree now you guys tell me....

Yeah, I got hit redface.gif :( :mad:

Maybe I can go back & get them to put a OD lock out in at no cost to me to make up for it. ;) tongue.gif ;)

I'll let ya know....