I`ve said it many times, the vendor (ZF in georgia [?]) chrysler is using to manufacture these differentials for them is costing them customers. I know i will NOT buy another dodge product just for this reason alone. I`ve had 2 brand new 4th gen (hemi) trucks, differentials are junk in both of them and i cant even get them to fix them. The dealer just tells me to drive it until it drops. What the hell kind of service is THAT...! Chrysler KNOWS these diff`s are junk but the dealers aren`t helping the situation any. Some dealers fix them some dont.

 

unbelieveable!! I'm getting the same feeling about my tranny!!!

 

Just had my Pinon seals replaced under warranty for a whine, dealership had the truck for less than 24 hrs as I brought it in midday. Don't know why they went, but they were replaced for free to me, that's all I care about.

 

What did pinion seals have to do with whine? They are to keep the fliud in. Seals are not a long repair. Usually under a hour per differential. A differential can be totally rebuilt in around 5 hours by a experienced tech.

 

I had whine (3.55 gears, no LSD) and they replaced the rear diff at around 14K miles. It's been beautifully quiet since (now at 24,800 miles). I would get it swapped out before the warranty goes.

 

According to your math/numbers, yours should start whining again in about 4,000 miles...lol.
14K seems to be the magic # when they start to whine, mine did, 2 dealer`s wont fix mine until it blows.
Isnt it nice how they will do nothing and let it become a hazzard & inconvenience to some people..?
Some dealers fix them on the spot, some dont, just depends on where you go to have it looked at.

 

I did put on a Mag Hytec diff cover, which about doubles the gear oil capacity. It should also help cool it better (supposed to). Hopefully the math thing doesn't pan out... At least my dealer was responsive and fixed it quickly.

 

I'm at almost 70k now and mine has started to whine, actually getting a bit loud. You can really hear it with the rear window open at slow speeds. Usually have the music on so I never really noticed but again, it is getting loud and now that I know it, I hear it all the time. Never noticed it before the pinion seal leak was fixed and I had the diff fluid changed. I was thinking of getting a siphon from NAPA and changing the fluid again using some Mobil 1. NAPA wants $16 bucks for a siphon pump. I pulled the rubber plug and checked, the fluid is up to the drain hole. Looks like a 5 minute job to do the fluid change. Maybe they put 75 weight in the rear when doing the 4x4 service since I do not recall any whine prior ? Dealer this time took the diff cover off when servicing, the first dealer ( where I purchased truck from ) just siphoned it out. This looks way to easy to pay someone to do if they just siphon it and is a quick rule out before I get them to do a gear swap. Almost ready to trade the truck anyway, we just put a superchips tune on my brothers FX4 Ecoboost and I'm trying real hard to stay out of the 3 Ford dealer lots we have in the area ! I hope we have tuning options with the new Rams when I am ready to do it, still think the Ram Sport is the best looking truck but I have always has a tuned truck over the past 12 years and returning to stock for dealer trips sucks, Dodges MDS really sucks and needs an option to be disabled as a user option in the EVIC.

 

Its not the fliud. It was when the SEAL WAS INSTALLED the tech screwed with the pinion PRELOAD taking the pinion in and out. There is a procedure for pinion seal replacement that NO ONE follows. They just unbolt the yoke and then the pinion nut,remove and replace seal then reinstall nut to the spot they hope it was before. Yours was not reinstalled to the same spot! Tech screed up your pinion preload and change pinion to ring gear clearance!

 

Also, sucking out the gear oil from the top doesn't get the crap that settles on the bottom of the case. Both times I've pulled the cover and flushed out the case with carb cleaner,...well you'd be amazed at the sludge that comes out. I would not just get the oil siphoned out.

Sounds like you want the Ford anyway, so I'd just pull the trigger...