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axle neglect

3K views 20 replies 13 participants last post by  Grogg 
#1 ·
Hey guys. Upon learning more about my new to me pickup by reading the service/drivers manual, it says to change the front and rear axle fluid about every 30,000 miles! holy cow I've got 105,xxx on it now with no knowledge of it ever being changed! (and I've known this pickup since mile 1). Could I be in for a world of hurt? I think I'm gonna get some fluid today and work on it this long weekend. from reading other posts, these axles have a reusable gasket? In the past with my 2500 gasser, I've only used mopar fluids for the axle/trans. is this a waste of money?

I emailed dodge about build sheet and it came back with a 5200# front axle. I'm assuming this is the AAM axle?

Thanks guys and happy thanksgiving!
 
#2 ·
30k intervals are way too soon for axle lube, my opinion. Heck, neither of my trucks got axle lube until well over 100k.

Both your axles are AAM; 9.25 up front, 11.5 out back.
 
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#3 ·
In the past with my 2500 gasser, I've only used mopar fluids for the axle/trans. is this a waste of money?
Yes it is, but not as much of a waste of money as using amsoil.

Sorry, that was my blatant attempt to stir up crap.
 
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#4 ·
I figured someone would attempt this :D I'll do some researching on what fluids you guys are using. Sometimes for me it's piece of mind knowing I have what the engineers recommend for fluids etc... yeah I'm one of those guys...:thumbsup:
 
#6 ·
Your rear end will be black and your front end will look like honey unless someone has been playing in deep water or mud. I use Valvoline fluids - personal choice. Has worked great. You DO want synthetic. Also, I use red RTV to seal the covers. Mine did not have the reusable gasket.

Change the rear and then do it again in 30K miles. My front hasn't been changed in over 100K and looks like honey. My rear is like honey after a few changes.

Here's a link to your factory service manual. Have fun!
https://www.dropbox.com/sh/81mtpw6h29nct9h/AADFUT79CVpu_LcpdZOLxp5ja?dl=0
 
#7 ·
I got 75-90 from the dealer & have re-usable gaskets on front & rear.
 
#8 ·
I once saw some info indicating that conventional gear oils might be better than synthetic because they seemed to transfer heat better, thus keeping the diffs a bit cooler. I domt recall where i saw this but i do seem to remember that they had the data to back up the claim.

Anyone heard anything along those lines?
 
#9 ·
Change it every 50k and look for filings in the case until you replace all the bearings. The OE bearings are really sub standard and you can catch things a LOT earlier if you are changing fluid and looking the wear dust. Yes, it will show on the plug as it is magnetic but there will be more in the bottom of the case.

Then it will depend on how hard you work it and the severe conditions it is subject to. Heavy towing and lots of water and mud change sooner and check periodically. Muddy water doesn't make very good lube.
 
#11 ·
I run Amsoil Severe Gear 75W90 in the front and rear. With Mag-Hytec covers, the front holds 4.5 quarts and the rear holds 8 quarts. :thumbsup: Looking in my log book, the oil change intervals have been somewhere between 30K - 40K. The diff covers make it easy since they have a drain plug and magnetic dipstick.
 
#12 ·
Hey guys. I went to the dealer today to get some oil. It was $25 a quart. I couldn't stomach that so I went to NAPA and got this valvoline http://www.valvoline.com/our-products/grease-gear-oil/synpower-full-synthetic-gear-oil It says GL-4 and GL-5 and limited slip on the bottle.

So I should be ok to put that in when i refill it? The dealer was saying I will need to add limited slip additive, but on this bottle it says limited slip.

Do i need synthetic for the front axle as well, or can i get by with the normal valvoline?

I apologize for the newbie questions, I just want to make sure I've got the right stuff so things don't go boom! :D
 
#14 ·
Valvoline GL-5 75-90 is just fine for both axles. That is what the dealer fluid is anyway, just in their own packaging.

No additive needed, the GL-5 is rated for these types of LS's.
 
#15 ·
Well I'm pleased to say I changed the rear diff fluid this weekend and the fluid still looked pretty good. It was a darker honey color. Before I drained it, I looked inside through the fill hole and saw a good reference point where the fluid level was at, then filled it back up to that reference point. It was about 3.5 quarts I added. Not quite the 3.81 quarts it calls for. Wasn't really sure how to measure 3.81 quarts to begin with... I'm horrible with math magician :D
 
#16 ·
I think there is a spec in the owners manual for that. Something like, from even with the bottom of the fill plug, to 1/4or1/2" below.
 
#17 ·
I have always filled until it starts to run out the fill plug. Mobil 1 75-90 every 50k or so. I also put the AAM max tow cover on the rear that comes on the new trucks.
 
#19 ·
Not gonna hurt a thing. If you pull HEAVY a LOT, a bunch of guys go up to the 85/140 in the rear end. Not needed for normal operation.
 
#20 ·
What rgsauger said. You can always use the additive for peace of mind, just siphon out as much as you need to put in. Just did mine the other day and put in the valvoline with the additive already in it because it was cheaper and wouldn't hurt anything.
 
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