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Changing Diff Covers and Best Diff Fluid

swbooking

NAXJA Forum User
Anyone used any of that AMSOil diff fluid or anything like that? like it or dont like it? anyone have any recomondations? Im going to change my diff covers to rock crusher manufacturing ones so im going to have to change the fluid. You just fill the diff to the plug right? thanks guys.
-Allen
 
cool, and you just fill it to the plug level and thats it right?
 
swbooking said:
cool, and you just fill it to the plug level and thats it right?

Factory wants fill level 1/2" below fill hole.Everyone I know fills it till it runs out.
Wayne
 
Mobil-1, Valvoline, Drydene, Amsoil synthetic [the only one thats sae certified] gear oil. See if you can find a reuseable rubber gasket for the diff cover, makes it a bit easier on future changes, also with using synthetic the gasket won't dryout, permanently form or otherwise be un-reusable. Avoid cork or the cork composite, get the plain black one, the last one I got was felpro. I just hate using RTV...
 
swbooking said:
Anyone used any of that AMSOil diff fluid or anything like that? like it or dont like it? anyone have any recomondations? Im going to change my diff covers to rock crusher manufacturing ones so im going to have to change the fluid. You just fill the diff to the plug right? thanks guys.
-Allen
The Rockcrusher cover has a much higher fill plug than stock,youd over-fill it if you topped it off.
diff_cover.jpg
 
Insure you do not have a limited slip differential in the rear. I THINK you would have to have a 44 to have a factory LS dif. If you do you have one will need an additive or a diff fluid made for same.
 
RichP said:
See if you can find a reuseable rubber gasket for the diff cover, makes it a bit easier on future changes, also with using synthetic the gasket won't dryout, permanently form or otherwise be un-reusable

Any suggestions on particular brand/type?
 
IntrepidXJ said:
with as often as i end up opening my diff up, it would get too costly using the expensive gear lube. maybe for my tow rig, but not my trail rig

the florida mud gets to my inner axle seals after about 3 times out.. so i have to change my gear oil way too often to consider going to synthetic again.
 
splitz said:
Any suggestions on particular brand/type?

The last time I bought them they were felpro, got them at NAPA one week day when I was home and they were open...
 
thanks guys, so if i over filled it, considering it has a higher fill plug to allow more oil, would it be bad? and ill get a gasket down at nappa next week. Thanks for the tips guys.
oh and i dont have an LSD in the rear. open diffs.
 
So then it should just balance itself out right? if theres too much it will just bleed out and go to a level that will work... sounds good.
 
No,its not that simple.Over-filling can cause "seal blow-out" and other issues!Crawl under a few vehicles,most run a level just above the bottom of the tubes.If you have wet axle bearings(D30's dont) they just need to be "bathed" in oil "not Drowned".
 
wow this got a lot more complicated than i thought it would be, so is there an optimal quantity? like a quart or something?
 
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