Rear Axle Noise-advise needed

[brillmtb]

Some time ago I replaced my rear axle fluid with Amsoil. I cant remember if I put in the additive but might of. I realize there has been confusion as to whether it needs it or not. I have the 03 2500, 4wd. I now am getting a noise/vibration when I am turning uphill from a dead start. No other time.

Should I have used amsoil, should I replace the fluid or add the additive or is this normal or not. 134,000 mile on the truck and not driven that hard.

 

[orhusky]

I have used AMSOIL for the last 30K miles with no problems and no niose... .....

 

[Prairie Dog]

You do not need the additive since you don't have clutches in your LSD.

 

[NIsaacs]

and if you did add the additive, it should be fine. What weight oil did you use?



Nick

 

[rscurtis]

If your truck is a 4X4, check the condition of your front axle u-joints. Whether it is or not, check the condition of the rear DS u-joints.

 

[brillmtb]

If your truck is a 4X4, check the condition of your front axle u-joints. Whether it is or not, check the condition of the rear DS u-joints. [/QUOTE



The sound is definitely from the rear. how would a rear u joint cause that with turning. It seems like this would be coming from the limited slip dif.

 

[steved]

You do not need the additive since you don't have clutches in your LSD.

Actually the AAM Trac-Rite does have clutches... they are termed "shoes" on the IPL. While they don't require additional LSD additive normally, I believe you would find that the OE fluid likely contains LSD modifier... and that LSD modifier content probably varies from brand to brand, which is why this issue pops up from time to time.



I have had the same thing occur as the OP, I changed from Royal Purple 85w140 (with over 100k on that fluid) to Schaeffers 75w140 (which has moly) and immediately had LSD chatter. Two bottles of Mopar LSD additive cured mine... that was over 40k miles ago, and the LSD chatter has not returned. Adding the LSD additive was recommended by another member of this forum a while ago.

 

[brillmtb]

Since I am running the 140w Amsoil and Reno is in the teens in the AM I wonder if that has something to do with it. Cant say I noticed in the summer. Since additive does not hurt that might be a cheap fix. Otherwise I am afraid more costly repairs are in my future. I guess I could tell my wife a new truck is in order although I keep hearing that most like the 5. 9 better.

 

[steved]

Since I am running the 140w Amsoil and Reno is in the teens in the AM I wonder if that has something to do with it. Cant say I noticed in the summer. Since additive does not hurt that might be a cheap fix. Otherwise I am afraid more costly repairs are in my future. I guess I could tell my wife a new truck is in order although I keep hearing that most like the 5. 9 better.

I ran my 85w140 Royal Purple in temperatures approaching -25*F ambient without any strange noises...



I would definitely source the Mopar LSD additive as it was indicated to be one of the better juices on the market... it comes in 4oz bottles if I remember correctly, and it took two bottles to cure mine (but my differential also has a high capacity cover and holds around nine quarts).

 

[SRadke]

If you've never replaced the rear u joints I'm betting it needs them and that is the root of your problem.



-Scott

 

[steved]

If you've never replaced the rear u joints I'm betting it needs them and that is the root of your problem.



-Scott

I thought the OP indicated the issue happened during an aceleration and a turn? A ujoint (thinking of one siezing) would vibrate all the time?



I've had both... that's how I remember it?

 

[DUBLR]

Go to Autozone and buy a tube of the LSD additive. That will cure it. Happened to my truck first time I changed the diff fluid. Guys will say no need but if it works you have nothing to lose. I run Mobil 1 pure synthetic.

 

[brillmtb]

Dont ask me why as the manual clearly indicates I dont need LSD additive but i put in some and my shudder is gone. I did notice that my fluid level may be a little low with my Amsoil 140/90 so I will top this off as well. dont know where it would have gone given no leaks and I filled it to just under the hole when I replaced the fluid. something strange with the advise dodge is giving for these rear ends and LSD additive needs?

 

[MChildress]

I have 70,000 on Royal Purple no additive and have had no problems.

 

[Trino]

I have same problem shudder at take off and a howl running at 70 mph. Or at 2000-2200 rpm... . have amsoil in diff. 70,000 mi...