Dodge Factory LS Diff Fill

[sam]

I saw a TSB from Dodge that said to use Synthetic 75w140 in their 1500 series Diffs and I have seen a couple posts from people saying that they changed the rear fluid to synthetic almost right after buying them, So does dodge put synthetic fluid in the rear from the factory or not. My 03 Ram 1500 is only 2 months old and I plan to do some RV towing this summer and am wondering if I should get diff oil changed first.

 

[Greaser]

I doubt if they use that weight and quality lube unless a tow package is ordered with the truck.Just did a 2000 Dodge truck rear axle...guy was getting a noise from the rear...tows a horse trailer twice a week..8 hours round trip each time...fluid that was in there was very dark and extremely low...put in the 75W-140 synthetic (Pennzoil) and it's quit now...probably just got it in time...I have been using 75W-140 synthetic (Mopar brand & Pennzoil) in both my Jeep's rear axles for 4-5 years now...haven't heard a peep out of them yet.

 

[Greaser]

I doubt if they use that weight and quality lube unless a tow package is ordered with the truck.Just did a 2000 Dodge truck rear axle...guy was getting a noise from the rear...tows a horse trailer twice a week..8 hours round trip each time...fluid that was in there was very dark and extremely low...put in the 75W-140 synthetic (Pennzoil) and it's quite now...probably just got it in time...I have been using 75W-140 synthetic (Mopar brand & Pennzoil) in both my Jeep's rear axles for 4-5 years now...haven't heard a peep out of them yet.If you have the Limited slip use the bottle of friction modifier...even if the lube you are using says it's in there allready..extra insurance for a chatter out back.

 

[Dick in Falls Church]

Sam-
To the best of my knowledge, there is syntethic in there from the factory. Go ahead and run it for a while, anyhow.

Keep in mind that the factory does not necessarily buy the top of the line synthetics.
I've heard that they will change supplier for a difference of 4-5 cents per gallon.

 

[twentynine]

I don't know about the new Dodges but my '99 1500 owner's manual says, if you plan on towing change the differential lube to 75w-140 synthetic.

 

[Doug Hillary]

Hi,

the reason I always change my gearbox and diff oils before about 3000 miles is to get rid of manufacturing and assembly debris. It also stops chemical buildup on seals etc. if non synthetics were the factory fill

Synthetic goes in there then - to stay
I've done it on advice from manufacturers - since the early 1980s

Regards