Changing Diff Covers and Best Diff Fluid

[swbooking]

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

[XgeekstarX]

regular gear oil does just fine. i heard about getting some extra mileage with switching to synthetic.. but i tried and didn't get anything.

[swbooking]

cool, and you just fill it to the plug level and thats it right?

[XgeekstarX]

cool, and you just fill it to the plug level and thats it right?

yep, you might wanna invest in a 4 dollar fluid pump so you're not fighting with trying to fit the bottle in between the tie rod and fill hole

[Wayne Sihler]

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

[RichP]

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...

[RCP Phx]

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.
http://www.rockcrusher-mfg.com/products/back/images/diff_cover.jpg

[langer1]

I added a drain plug to my stock cover, also I do recommend Amsoil synthetic in the diff not in the engine though.

[badron]

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.

[IntrepidXJ]

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

[Jim63]

The Rockcrusher cover has a much higher fill plug than stock,youd over-fill it if you topped it off.
http://www.rockcrusher-mfg.com/products/back/images/diff_cover.jpg


so how much should you fill it up with this cover?

[splitz]

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?

[XgeekstarX]

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.

[RichP]

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...

[swbooking]

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.

[DementedXJ]

i don't see how that little of extra fluid could be bad but i don't know how much the fluid expands while hot.

[IntrepidXJ]

if you over filled it, the fluid will come out of the vent tube when it gets hot

[swbooking]

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.

[RCP Phx]

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".

[swbooking]

wow this got a lot more complicated than i thought it would be, so is there an optimal quantity? like a quart or something?

[RCP Phx]

Recieved my 3 covers from Rockcrusher today,the Ruffstuff cover should be here soon.As far as oil levels go Im thinking about tapping a "sight" hole in them,Ill decide that later,paints drying now!

[swbooking]

i just talked to my friend who works at offroad evolution and he told me all you do is look in the chiltons/haynes and it will tell you the amount to put in. then you should be golden. :)

[lawsoncl]

i just talked to my friend who works at offroad evolution and he told me all you do is look in the chiltons/haynes and it will tell you the amount to put in. then you should be golden. :)

I don't trust Haynes or Chiltons to be accurate. Just look at the old cover and figure out about where to fill it on the new cover. Really, it's not rocket science.

[swbooking]

I don't trust Haynes or Chiltons to be accurate. Just look at the old cover and figure out about where to fill it on the new cover. Really, it's not rocket science.
haha thanks. good thing its not, cuase im an electrical engeneering major hahah :laugh3:

[RichP]

Recieved my 3 covers from Rockcrusher today,the Ruffstuff cover should be here soon.As far as oil levels go Im thinking about tapping a "sight" hole in them,Ill decide that later,paints drying now!

Who sells something like that ? I've seen it done on a NP T/C where the fill and drain plugs are connected with a plastic hose but I've not seen a source for sight glasses. They have to be out there, they used them in A/C systems so they gotta be made by someone...

[RCP Phx]

Im just talking about adding a 1/8"NPT plug where I want the oil level to be and using the 3/4" plug to fill with!

[swbooking]

^^^ thats a pretty good idea...

[RCP Phx]

Who sells something like that ? I've seen it done on a NP T/C where the fill and drain plugs are connected with a plastic hose but I've not seen a source for sight glasses. They have to be out there, they used them in A/C systems so they gotta be made by someone...
Were theres a will theres a way!Sight glasses for Holley carbs!
http://static.summitracing.com/global/images/prod/large/hly-26-112_w.jpg

http://static.summitracing.com/global/images/prod/large/hly-26-113_w.jpg

[RichP]

Now thats pretty cool, wonder if the plastic ones show color from the sides when full and go clear when below full. Gas safe so they should be good with oil, maybe, the sulphur content might pit them from the inside over time but for $5 who cares...

[swbooking]

Thatd be cool, just drill and tap. easy as that. hahah does it come in a kit with the drill and tap?

[RichP]

Thatd be cool, just drill and tap. easy as that. hahah does it come in a kit with the drill and tap?

Doubtful, the carb float bowls already have the holes. You'll have to buy one or better yet go spend $100 at sears and get a decent tap and die kit in a case. I was suprised at how often I used mine after I had it, came in handy for chasing rusted stuff and cross threaded crap from sloppy mechanics....
I really did use it alot and added to it as necessary, especially after we rebuilt the TJ from the rollover, put the lifts in and all the other work. Now when I pull something and the threads are messed up I grab the kit, some lube and spend the extra 5 min to fix it right.

[swbooking]

yeah seriously, i have the RE hack n tap SYE on my Xj and itwas nice to use the tap to mount it. (Well not really nice a PITA but atleast its right) and also to fix a bolt on the crossmember and a spring bracket. i need to get a set though. i only have a few here and there more like 2 haha