How Much Fluid 4 Mag-Hytec

[dsaint69]

So I just bought a set of Mag Hytec differential covers for my toy. My mechanic says that I only need about a quart and a half of gear oil. Then I read the Geno's garage install and they say the rear may take up to 8 quarts and the front up to 6 quarts?? Is this right?? That seems too much does it not? They also say I should add some kind of additive?? Anyone ever do one of these that can help a brother out??



I have the 03 dually with the H. O. 6 speed if that helps any.

 

[MMeier]

Yep, just a hair shy of 8 qts. for the rear and I believe the front was a shade over 4, may be wrong on the front, but that will get you started.

 

[Bertram65]

There is no additive needed, does not matter if you have anti spin or not, if you want stock fill level for the rear it is around 5 quarts, the dipstick on those are covers are not calibrated to stock fill levels.

 

[dsaint69]

really?? Are you sure we don't need the anti-slip fluid even if I have the posi-rear?? Even the factory suggested it.

 

[MMeier]

No additive needed with the limited slip in a AAM axle, however I have to disagree with the above statement regarding the dipstick. Have 140k on mine since running this way and no problems, 165k heavy towing miles altogether.

 

[Bertram65]

No additive needed with the limited slip in a AAM axle, however I have to disagree with the above statement regarding the dipstick. Have 140k on mine since running this way and no problems, 165k heavy towing miles altogether.

I do not know nor did I say it would cause any problem but it is not at the factory fill level, it is way higher if you fill it by the dipstick.

 

[Bertram65]

really?? Are you sure we don't need the anti-slip fluid even if I have the posi-rear?? Even the factory suggested it.

Positive, and factory does not suggest it for the 11. 5" AAM axle with the anti spin option or the open differential.

 

[Bow66tie]

I received a set of Mag-Hytecs from Santa, but haven't decided which fluid to use. I'm leaning towards an Amsoil product, but I just don't know. Any suggestions on what you'd use and WHY would be appreciated!!!



Michael

 

[Bertram65]

I received a set of Mag-Hytecs from Santa, but haven't decided which fluid to use. I'm leaning towards an Amsoil product, but I just don't know. Any suggestions on what you'd use and WHY would be appreciated!!!



Michael

Mobil 1, meets the requirements and is readily available.

 

[dsaint69]

I have just ordered the amsoil 75 140 heavy duty with the pump. I just don't know whether to get this additive the instructions are quite clear

 

[Bertram65]

I have just ordered the amsoil 75 140 heavy duty with the pump. I just don't know whether to get this additive the instructions are quite clear

Why 75/140? I have always read the spec calls for 75/90. Amsoil application chart reconmends 75/90 GL5 for the 11. 5 AAM axle with no additive.

 

[Buffalo]

Mag-Hytec told me that the plug in the center of Name & Part # label, on the cover, itself, indicates the "factory fill level".



When I asked them about possible foaming issues with their recommended higher oil level, they said that they had never experienced problems or complaints. With that information, I went with the higher level & have not seen any problems, yet!!!



This last gear oil change, I went with Redline 75/90. I got it for $7. 00/qt. , as opposed to $21. 00/qt. that Mopar was asking. I even went to the local Chev. dealer thinking that their trucks use the same AAM axles. They wanted $25. 00/qt. Hell, you could put an excellent bottle of Scotch in there for less money.



Joe F. (Buffalo)

 

[CLynch]

Originally, DC was recommending no anti-slip was necessary. I believe that has changed and it should be used if you have LSD. I plan on using amsoil 75-140 in the rear since I tow.



Craig

 

[Matt400]

Mag-Hytec told me that the plug in the center of Name & Part # label, on the cover, itself, indicates the "factory fill level".



When I asked them about possible foaming issues with their recommended higher oil level, they said that they had never experienced problems or complaints. With that information, I went with the higher level & have not seen any problems, yet!!!

A friend of mine just bought a 3rd gen with one of these on the rear. I was looking for some info on the fill and found your post.

Odd why the cover maker would suggest a higher level than the axle maker.



Good to know about the plug in the center, thanks for posting that. I have seen some axle seal trouble but can't confirm if it was due to over filling. My friends truck has pinion seal seepage at only 38K miles.

 

[CDonaldson]

I was told by my dealership to use 75w140. They said that there was a service memo (or some name like that) from DC regarding the use of the 75w140 instead of the 75w90. As I see it, hot roads, towing, etc I was going to use the 75w140 anyway. I have the MagHytec cover, filled it with just right at 8qts of AMSOIL Severe Gear, everyone I know uses the dip stick level without any problems. No need for the anti-slip, AMSOIL has that covered in their product.



CD

 

[MMeier]

I was told by my dealership to use 75w140. They said that there was a service memo (or some name like that) from DC regarding the use of the 75w140 instead of the 75w90. As I see it, hot roads, towing, etc I was going to use the 75w140 anyway. I have the MagHytec cover, filled it with just right at 8qts of AMSOIL Severe Gear, everyone I know uses the dip stick level without any problems. No need for the anti-slip, AMSOIL has that covered in their product.



CD

True, but the AAM axle does not require the additive as it is.

 

[RAlberg]

additive question

Originally, DC was recommending no anti-slip was necessary. I believe that has changed and it should be used if you have LSD. I plan on using amsoil 75-140 in the rear since I tow.



Craig

Is there more than one additive? I have lsd on 2005 dually and purchased additive from dealer. Small print on bottle says it is for noise reduction. Is there another additive to improve lsd? How much do you put in with maghytec cover?

 

[CDonaldson]

MMeier - You are right, our axles do not require the LS additive according to our manuals and also the shop manual. I do recall a discussion about the LS additive, and there was some discussion about it being used for noise reduction, but also over on Carson Dodge's site there is discussion about DC now telling the dealers to add it to the AAM's. So - who knows???? I guess it cannot do any harm, that is the most important part if you add it.



CD