2nd Gen Non-Engine/Transmission when should I change differential fluid

[Breed]

I bought my 98 brand new and never plan on selling it because I Love the truck and works great pulling my Fifth Wheel. The truck has about 98,000 miles on the clock and a coupla years ago I changed the real differential fluid and used Amsoil synthetic Oil. When should I change it again? I would say the fluid has about 30,000 miles on it and the rear end is has posi traction. . I have the new fluid from Amsoil and was wondering when I should change it. Any comments would be greatly appreciated. The Truck is used mainly to tow and I have used synthetic Oils and grease for the last 9 years. I change the Engine once a year with synthetic Oil and grease.

Thanks.

 

[Jim W]

I do not know the service interval for 2nd gen trucks. I own a 2008, 3/4 ton 4X4 and changed my Diff fluid at 15K both front and rear. This is the recommend service interval by Dodge.

I will be changing every 30K from now on. I am using Asmoil and have Mag-Hytec covers front and rear for added capacity. This will help with the 30K interval that I am now using.

My old Chevy 3/4 ton 4X4 truck service interval was every 30K so this is why I feel comfortable using the 30K interval instead of 15K interval.

Jim

 

[JKreiss]

I'm running Amsoil and just did the 30k. It looked as clean as when i put it in. I'm thinking it could go a lot longer but i'm going to drain it again in another 30k and go from there.

 

[HBarlow]

With Mag-Hytec covers I changed the differential lube on my '01 (Dana) and '06 (AAM) rear axles at 50k intervals. I never saw any evidence of lube breakdown or component failure resulting from the extended interval. 325k miles on the '01 and 230k miles on the '06.

 

[jgillott]

I change it in my trucks every 50K. The fluid has always looked great. Now I realize that without an analysis, there's no way to tell for sure by look or smell, but there have been no ill effects with using that drain interval over hundreds of thousands of miles.

 

[HBarlow]

My thought has always been that the 15k interval specified for Gen III trucks with AAM axles is simply for the benefit of dealer service departments needing work.

 

[Texis]

The LS additive breaks down in my trucks rear axle and I use this as the "meter" to change the fluid. I typically get about 30K-40K out of a rear axle fluid change, including the additive.



It always does the same thing, the truck starts pushing in turns and I can hear the front tires chirping. Basically the rear LS is not releasing. It really puzzled me the first time, I assumed something was wrong in the front end. I finally realized what was happening and changed the rear fluid + new additive... . bingo, no more chirping or pushing.



Now when it happens I know to change the fluid + additive, as mentioned typically at the 30K-40K mark. Works every time. I have been though this exercise 5 or 6 times in the last 200,000 miles.



BTW, I typically never tow anything... just major highway miles.

 

[AABEN]

I bought my 98 brand new and never plan on selling it because I Love the truck and works great pulling my Fifth Wheel. The truck has about 98,000 miles on the clock and a coupla years ago I changed the real differential fluid and used Amsoil synthetic Oil. When should I change it again? I would say the fluid has about 30,000 miles on it and the rear end is has posi traction. . I have the new fluid from Amsoil and was wondering when I should change it. Any comments would be greatly appreciated. The Truck is used mainly to tow and I have used synthetic Oils and grease for the last 9 years. I change the Engine once a year with synthetic Oil and grease.

Thanks.

FIRST I would look at the book that came with the truck that tells you all the INFO. That is what should be done.

 

[firefighter]

Firefighter

I would change all my fluids at least once per year,more if you do high milage.

 

[Breed]

Thanks guys, really appreciate the information, I am going to keep this truck a long time, as I love it from the first day.

 

[Skydiver]

On the axels there is no soot or carbon emissions from combustion to contaminate the lube oil. Only moister and metal filings. The front axel is more subject to condensation because it is used less. Always good to operate the front axel at least 10 miles each month.
I change mine around every 5 years or 50k.

 

[Breed]

Thanks again, good idea.

 

[JMcCoy]

FIRST I would look at the book that came with the truck that tells you all the INFO. That is what should be done.

The book that comes with the truck does not take synthetic fluids into account. Driving styles, payload, viscosity, and how many miles you drive a year also needs to be accounted for. If you drive low miles, synthetics will last several years where petroleum oils will not. The BOOK is useless.



That said, I will go no more than 30 on synthetics and 15 on petroleum. This is with a mix of easy and hard use. If my driving style changes, I will adjust accordingly. Good luck

 

[Breed]

Thanks, I really like Amoil and their products. It has Amsoil in the rear end, and ATF and Shell Rotella 15/40 synthetic in the the CTD.
Thanks again for your info, it certinally is appreciated. I love my 98, it still does not have 100 k miles after crossing the US three times. I bought it new and have taken excellent care of it.

 

[Jetson]

I change diff oil every 80 to 100K. I have a Mag-Hytec cover so it holds a little more. I put LE-607 in at 80K and replaced it at 205K with Royal Purple, so OK I go over 100K sometimes. I have a Dana 80 LS.

 

[Breed]

Thanks, I really appreciate the input.

 

[Midnite]

I would change all my fluids at least once per year,more if you do high milage.

Changing all fluids once a year as a minimum as you describe is unnecessarily frequent. If you don't mind doing the work yourself and don't mind the cost of the fluids, certainly go for it. No truck ever died from too frequent servicing.



Most of us aren't made of cash though, and can safely adhere to Dodge's recommended service intervals. Of course, if you have things like Fastcoolers on your manual transmission, or Mag Hytec transmission or diff covers, then you have excess fluid capacity and can safely extend your fluid change intervals (unless you do things like fording creeks, in which case the recommended change intervals are out the window because you almost certainly suck water into the axle tubes)



Mike

 

[Breed]

Thanks Midnite! good points.