Just got off the phone with the local Dodge Dealership about changing the fluids in the axles. They want 129$ a piece to replace the fluid. I asked why so expensive and he claims that there is a special additive (friction modifier?) that has to go in with the synthetic lube. He said that major damage would eventually occur if this was not added. That is CRAP! I'm not going to spend 260$ bucks to have some guy change my fluids. For those of you have changed your fluids yourself, what are yall using? I appreciate your information and any help you may be able to provide.

 

Just say no to additives. The AAM's do not need it with or without limited slip. Any synthetic GL-5 75W-90 meets the required specifications.

If you are in Vegas, I will come to your house and do it for you for $ 250 or you can do it yourself for about 60 bucks. You do not need a gasket, they are re-usable.

 

You guys are awesome. I don't post here often but I read the forums every day. The information obtained on this site is priceless. By the way, I'm in Houston. Why are they recommending this additive? Crazy stuff, as if these vehicles are not expensive enough to operate with the cost of diesel.

 

One more question,...to do both front and rear, how much fluid should I buy and what is the recomended brand around here? Thanx Everyone.

 

Tell the Bozo to read the shop manual about friction modifiers. While it will not hurt the axle, they are not needed. And even if it was, the stuff is about 8 bucks a bottle. I use Redline 75W140 in mine and so far it has been working for me with a heavy trailer. My original ring and pinion went south at 12K using the expensive DC stuff.

 

Nice truck Casey. I'm glad to know that I don't have to shell out the dough for DC's stuff. Can you pick up the redline at any automotive shop?

 

I had my rear changed out at 30,000 I had my personal mechanic do it for me. He used the oil from the dodge dealer but didnt get the friction modifier. after i got my truck back from him i had this annoying shutter feeling. for about 2 weeks I checked everything, I thought for sure it was the tranny. almost had it flushed but just added some lube-gaurd, didnt solve the shutter. couple days later i read on this forum about some special additive (the friction modifer) so i decided to call my mechanic and he said he did not put that in. He gets the stuff from dodge, i pick it up the next day, put it in that night, take it for a ride, never heard the shutter sound again, and this is 15,000 miles later (knock on wood). Im sure there is another rear end fluid you can use but i used stuff from dealer with no additive and it shuttered.... but anyways the truck sure acted like it wanted the friction modifier
just my .02

 

The AAM axles do not require the friction modifier. With that said, every rear end is different, whether it calls for the modifier or not. And, every differential reacts differently.

Some guys on this forum have changed their fluid to the Amsoil 2000 series 75w-90 and experienced a shutter from a stop, making a left turn. They changed the fluid to Valvoline 75w-90 oil and the shutter went away. I had changed my fluid at 7500 and around 26k miles noticed the shutter. I changed to Redline 75w-90 that came with the modifier and the shutter went away. Amsoil no longer makes the 2000 rear fluid, it's called something else now.

So, it's personal choice, The DC stuff, Amsoil, Redline, Valvoline, Mobil 1, or Royal Purple....to name a few. I think you'll find most guys are running Redline, Valvoline or Mobil 1 and are very happy with the results.

Frt & Rear Axle (up to 5 pts frt & 8pts rear/8 qts total) GL-5 SAE 75W-90 Synthetic.

 

I got a shudder on turns after changing my oil, added the modifier no more shudder,spoke with my buddy at the dealership and he found a TSB stating that modifier is to be used in all AAM axles.

 

Getting ready to change my fluids soon , not sure what to buy now !!! Redline is going in , guess getting it with modifier already in won't hurt anything .

 

It's been my experience, that most synthetic lubes for drive axles already contain enough internal friction modification for limited slip units, that the "external" friction modifier is not needed.

If you have a limited slip unit, make sure to drive several tight figure of 8 patterns in a parking lot after a fluid change, to ensure the new fluid is worked into the clutch packs. If chatter exists after this, then purchase a bottle of friction modifier, and only add a little at a time, until chatter stops.

Group 5, ester synthetic basestock is an internal friction modifier. Redline oil has been known to use this basestock primarily, so I think chatter would be less likely with this lube. An MSDS of any particular lube should show the percentage of polyolester it contains.

 

Redline makes two 75w-90 gear oils. The first one 75w-90 comes with a modifier and the 75w-90 NS that doesn't. I used the regualr 75w-90 and the shutter went away. I know it makes no logical sense, becuase there's no Clutch Disks in the rears of these trucks...
Valvoline also comes in both regular and NS formulas...

 

All SECOND gen trucks with DANA limited slip differentials have clutch packs. All THIRD gen trucks with AAM limited slip differentials DO NOT have clutch packs.

 

Thanks.

Redline is a bit hard to find. You can order it direct from the factory or you can check their website for distributors. I went the website route.

Casey

 

I had my front and rear diff fluid changed at a dealership. 7.5 litres is what was on my invoice. Along with an 8 dollar bottle of friction modifier. I told the service guy the friction modifier was not needed and he should check into it. I paid the extra 8 bucks, jumped in my pickup and left.

hilclmr,

Where is the TSB for the friction modifier? I would hate to be a knowitall at the dealership and in reality they are the knowitalls!