RDM16CTD

I changed the fluid in both the F & R diffs last weekend - and was double checking the level today, just to be sure.

I've never had confidence in my finger as a dipstick, to see how far below the fill opening the fluid is. Today I used an Allen wrench and it was ideal - the oil level shows up very clearly on the dark metal, and holding the wrench on the bottom of the fill opening makes it easy to measure - no more guess work!

This is a take-off on a tip I read on this forum - to use a bread wrapper tie bent to 90 degrees, but I couldn't find one.....

Lots of great advice here - changing diff fluid is definitely a good do-it-yourself job.

rockcrawler304

Good tip!! I usually fill mine until it just starts to pour out. I figure the more the better

DinosDiesel

i also changed my Diff Fluid today but i bent a hanger in the shape of a L. But your idea is good too.





It's not good to fill until it pours out because it creates Foam inturn you get slippage.

oilfield-trash

Get you a Mag-hytec dif cover and enjoy. drain plug, dip stick, sensor port......worth the money.

rockcrawler304

Not sure how this is true. I doubt an extra 1/4 quart will cause this. Not to mention the extra capacity covers like the Mag mentioned above would be even worse.

mj007

Good tip ..... I use baling wire sometimes ..... if it's a bit rusty it shows the lube pretty good, too.

AkitaSumo

....with magnets to collect all that metal...

DinosDiesel

That's True.
i wonder how high the level fluid covers the gears on the Mag-Hytec?

jrussell

It's supposed to be filled right up to the hole. A little less or a little more won't make a difference.

Mocho

I always just fill it right up to the hole and when I stick my finger in as long as theres oil on my finger I call it good, i'm to lazy to use some fancy thing to check it Tempting to buy a fancy diff cover though, but the price tag ain't cheap!

sallyman1

is this accurate? i heard on these aem axles/diffs we werent supposed ti fill up to the hole. i know on heavy trucks i do but was told inch below hole o n these dodge trucks. dodge had a bulletin out i believe

RDM16CTD

On the rear diff cover there is a line stamped into the cover, to the drivers side of the fill hole, that says 'oil level'. It looks like about 1/4" to 1/2" below the bottom of the fill hole. I looked for a similar marking on the front cover but could not find one.

The line is not marked very well - hard to see it - but on mine it is there.

I don't know it it's a problem to be over that fill line or not - I just used the Allen wrench to match up the fluid level with the line, and then used a similar amount on the front.

Would be nice to have one of those fancy covers from Geno's!

mj007

Yeah, I remember reading in some piece of Dodge info that the front diff. should be filled to within 1/2" of the bottom of the fill plug hole; that's what I do. I think we're both in good shape

hivoltage

good tip...thanks!

Mocho

The problem most of the time with filling up to the line is the fact that unless your truck is level it's either going to be higher or lower then the actual mark. I know it's still close, but your never going to fill it exact.