2nd Gen Non-Engine/Transmission Which Differential?

[AlFischer]

I am changing the oil in my differential. Using Royal Purple 85W-140.



I looked for the tag and expected it to show the type it was. The tag says:



52068459AJ

3. 54 606707-2



I know that the 3. 54 is the ratio. The cover is stamped DANA. Is this a Dana 60 or what? What is the top number?



Anybody using RP have to add the slip modifier or is the info on the bottle about not needing it true?

 

[Ram4Sam]

HO six speed trucks have D80... . Auto trucks have the D70. I have the RP 85-140 in mine, works fine without any extra modifier.



Sam

 

[BigPapa]

Front or rear?

 

[AlFischer]

The rear. It's a 2WD.

 

[BigPapa]

HO six speed trucks have D80... . Auto trucks have the D70.

There ya go.

 

[AlFischer]

OK. I thank you guys.

I was curious. The shop manual shows quite a few.

Curious mind wanted to know!

 

[HHhuntitall]

I will caution you on not adding the friction modifier required by Chrysler. It really doesn't hurt anything... ... except the clutches in the Limited Slip if you have it. No worries if you don't have it. If you do, eventually, you'll notice it clunking when you turn corners and accelerate hard. That's the clutches not slipping anymore.



Also, to identify your axle, just for future reference, on the front of the housing, I think on the driver side of the housing, below and to the side of the pinion, there should be a casting number in the housing, something like D70U or D80HD..... Any quality GL-5 gear oil will work fine.

 

[AlFischer]

OK. I will climb under it and look where you say.



Are you saying that I SHOULD add the friction modifier even though the RP 85w-140 says it is not needed?

 

[AlFischer]

OK. I just slid unde it and right there where you said it was actually cast in large upraised letter 70-20 3. 54!



And I READ the bottle of RP 85w-140 and it actually states that it contains friction modifier. Guess I will have to trust them but will watch carefully for and problems. I understand that too much friction modifier is just as bad as too little.

 

[Ram4Sam]

The RP works fine, right out of the bottle in mine, which is a limited slip unit. I am changing it soon as it been in for about 70,000 miles but is still smooth and quiet, no clunking.



Sam

 

[AlFischer]

Thanks. That good to know. I just test drove mine after a transmission fluid change and rear end oil change. Didn't notice any rear problems, but it took a while to get the transmission air out. It was shifting into low pretty bad from start. Got it up to temp, and now seems OK after 20 miles. Checked fluid and added a pint (Valvoline ATF+4). The price of the RP 85W-140 GAGGED me! $23/qt at NAPA.



Plan to drive down to town later to test it on PAVED roads. No paved corners where we live!

 

[HHhuntitall]

AH! I don't use Royal Purple any more, so I was unaware that Friction Modifier was already added. No worries!

 

[AlFischer]

Must have it!

Well it must have it. The label says so and I put in 3 qts and drove it. Appears to be OK. Last time I put in Valvoline and it took two bottles of modifier. Same in my son's 96.



NOW, the PRICE at $23 is ridiculous! Other similar products are $14-$15, But then you have to buy the modifier. Leaving next Saturday on a trip to the Grand Canyon. Plan to watch it close and hope it is OK. Looking at about 2K miles or so. Good test.

 

[GAmes]

I've put 700k on mine with RP and no additional additive. The LS works just fine. I buy mine by the case on Amazon, much cheaper than NAPA if you search a little. I change it every 50k.