Differential and Transmissions Fill Procedures

[ForTehNguyen]

first post in steve-indys thread seems to indicate that the castrol stuff has the modifier already

[kriskyk]

We're kind-of reinventing the wheel here. Steve-Indy has a very comprehensive thread on this subject: https://driveviper.com/forums/thread...erential+fluid

I changed the diff. fluid on my ACR last night (3rd change/4080 miles). Before draining, the fluid was full to the fill port and I drained it into a glass jar. I then put 1.4L (47.34 fluid oz or right at 1.5 qt) of Mopar 68197929AA in another identical glass jar. The fluid I drained was 5 oz more than the recommended 1.4L, which means filling to the fill port (as I did last time) is slightly over-filling with regards to the Dodge recommendation. Does it matter? Don't know, but I doubt it. BTW, in 1030 miles and 2 track days, the fluid had changed color from "honey" to a medium-dark gray - no burnt smell and still very uniform with no debris or sludge. Another BTW, changing your own fluids gives you the opportunity to get all of the bits of tire rubber and track debris out of the belly pan and to clean things up a bit. I bet the dealer doesn't do that.

Pappy

Just an FYI. Here is input from Dan Cragin about transmission fill level for track use (i.e. do not over fill until it leaks out the fill plug): https://driveviper.com/forums/thread...l=1#post300665

This kind of insight may be one reason why the recommended fill levels do not reach the fill plug hole.

Whats interesting, is I drained and filled both the transmission and differential today by measuring out the required volume for each in a graduated cylinder on a scale to get each of their net weight then put my motive power fill on the scale and zero'd it and filled each until I reached the same net weight measured for the required volume.

This resulted in both the transmission and the differential to be filled to the fill hole/plug.

[AZTVR]

If we use OEM Mopar axle lubricant, do we need to add an additive or not? Above procedure shows that you do need one, but others state that it is already included in the Mopar lubricant and there is no need to add the additive.

Be careful with the terms being used. There are two different OEM Mopar axle lubricant part numbers being discussed. If you read Steve-Indy's first post here: https://driveviper.com/forums/thread...erential+fluid You will see being discussed botj a Mopar fluid that requires a limited slip additive, and a different one that has the required additive included already in the proper amount. The latter fluid is described as the MOPAR labeled bottle containing the Castrol Syntrax fluid Limited Slip fluid that was designed for the Visco Lok limited slip.

The procedure listed above does not specify which MOPAR differential fluid that the procedure is written for for; but, because it says to add the limited slip additive, one would assume that it is NOT for the latest recommended MOPAR fluid that Steve-Indy references in his post.

[AZTVR]

first post in steve-indys thread seems to indicate that the castrol stuff has the modifier already

Yes it does, and it says that the new MOPAR fluid part # contains the Castrol fluid.

[kuishe]

only revision i would make to that procedure is, as a general rule, always open the fill port first. If for some reason you cant get the fill port open but you just drained the diff or transmission, youre going to be in quite the pickle. It will drain smoother with the fill port removed also.

So its clear here that the MOPAR supplied diff fluid does not have the friction modifier. I purchased the Castrol Syntrax one, im assuming it does have it?

Ya like the majority of us I too open the fill port first...

I open both diff drain ports compare to just 1 as per the manual. Cant hurt so might as well...

What really caught my attention is the manual says put the tranny in neutral. Is this crucial? Can anyone tell us why pls?

[Dr.Ron]

I was told by the Dodge parts guy that the Mopar 68197927AA is made by Castrol which has the modifier in the fluid already....and no where could he find that a modifier was required to be added.

[dewilmoth]

This is the same as the OEM fluid. No additional modifier necessary.

Castrol Syntrax Limited Slip Gear... https://www.amazon.com/dp/B07KQFV3K8...p_mob_ap_share

[Dr.Ron]

I did my diff fluid today and I put in a little more than 1-3/4 quarts and it still wasn't spilling out of the fill hole so I just stopped and closed it up. Any problem with that?

[Steve-Indy]

Seems odd, but admittedly, I don't recall the exact amount we used at our Special Viper Service Session last year when we changed the differential fluid on several Gen V Vipers ...2013 through 2017...all of which were stock, so no diff coolers.

The volume you mentioned seems high...noting the printed 2014 owners manual calls for a total volume of 1.5 quarts (48 oz) which equals 1.4 liters.

As often seems the case, the 2014 Viper Service Manual CD states 45 oz...BUT then uses the old mix of diff fluid and friction modifier which is of course incorrect.

If you don't have diff cooler lines, I might worry about overfill...which might cause foaming and/or venting.

Will be interesting to hear from others with wider experience.

UPDATE...courtesy of Tom Sessions: At our Service Sessions we used right at 1.5 liters...while filling through the correct fill port which should have an external tag and be just below the center line.

We BOTH wonder if you were filling the diff through the upper, plugged port to be used for a diff cooler return line. If so, you are over filled.

Somewhere on this forum, a poster put up a pic with labels for the diff.

[Dr.Ron]

Yes, I filled through the upper fill hole. The lower seemed too low to get any fluid in.
Yikes.
Should I remove some fluid now?

[Steve-Indy]

Yes.

I would carefully measure what you take out, and see if your math comes close to the 48 oz (1.4 liters) recommended.

FYI...the 500ml bottles of the same fluid that Mercedes sells actually have a very clever top that works as s spout to keep one from making a mess or needing a pump. Use three of these half liter bottles and you are done...with no waste.

[SSGNRDZ_28]

Yes, I filled through the upper fill hole. The lower seemed too low to get any fluid in.
Yikes.
Should I remove some fluid now?

Yes just open the middle port and allow it to drain to the correct level.

Doug

[Steve M]

Somewhere on this forum, a poster put up a pic with labels for the diff.

From the service manual:



And a pic of the Gen 5 differential I installed in my '08:

[Steve-Indy]

Thanks, Steve...you da man !!

[Steve M]

And here's a good example of why you don't need a ton of fluid in your differential for it to work properly (skip to 3:00 if it isn't already there):

[Dr.Ron]

What a neat display.
Thanks Steve and Doug!
I think I'll do this on jack stands vs. Moving my 2 classics to get the Viper on the lift again. And lucky me gets to remove the belly pan and its 1 million bolts again. Lol
I guess it could be way worse.

Ron