Q: Suggestions on synthetic rear differential oil for an '04 Marauder...

[Zim Hosein]

As the thread title states, I'm looking for suggestions on synthetic rear differential oil for an '04 Marauder. From my research here, I've read that if you have one of those little silver tabs bolted between the diff. cover and the diff. that an '04 owner should use 75w140. Is "Genuine Ford Fluid XY-75W140-QL SAE 75W-140 Synthetic Rear Axle Lubricant" the way to go (I know I will need 2 bottles, since the diff. takes ~ 1.8 quarts) , or should I purchase another 2 quart bottles made by another brand? Give or take a few dollars, I've seen Mobil 1, Royal Purple, Valvoline, etc. for around the same price shipped. Any & all input is appreciated.

Thanks in advance! :beer:

[Pat]

Jim, in your research did you find if a friction modifier is required?

IIRC the shop that changed out my differential oil used a friction modifier but I don't think the oil was full synthetic.

Regards,

[Zim Hosein]

Jim, in your research did you find if a friction modifier is required?

IIRC the shop that changed out my differential oil used a friction modifier but I don't think the oil was full synthetic.

Regards,

Pat, it's "Z"im ;) ; from my research I've read that using too much FM additive isn't suggested... :confused: I have read the specs from Royal Purple web site that some kind of FM additive is blended in their synthetic diff. fluid. :confused:

[fastblackmerc]

Go with a name brand full synthetic oil of the correct weight. Most full synthetic's do not require any friction modifier or any other additive.

I've been using Redline 75w/140 since I changed to 4.10's... no problems.

BTW... Ford changed the spec to 75w/140 right after they had the soft axle problem. The factory kit had a new tag that secified the correct weight lube.

[JustRight]

Mobil 1 and still use the friction modifier.

[RF Overlord]

Most fluid that already contains the FM will have a small black square with white "LS" (limited-slip) on the label or state that it is good for complete replacement of the factory fluid.

If it says it's only recommended for "top-up", then avoid it.

FYI, the Motorcraft fluid does not have FM and requires a bottle of XL-3 when used in the Marauder (all of which came with limited-slip).

[babbage]

Imho AMSOIL 75w-140 is the best gear oil you can get.

Has the FM in it already.

[MOTOWN]

Imho AMSOIL 75w-140 is the best gear oil you can get.

Has the FM in it already.

+1 you can't go wrong with Amsoil , or Redline these are the two best synthetic oils on the market.

[Zim Hosein]

Go with a name brand full synthetic oil of the correct weight. Most full synthetic's do not require any friction modifier or any other additive.

I've been using Redline 75w/140 since I changed to 4.10's... no problems.

BTW... Ford changed the spec to 75w/140 right after they had the soft axle problem. The factory kit had a new tag that secified the correct weight lube.

Thanks for the input fastblackmerc! :beer: I'll look at my FLAPS and see what they stock, but I'm not hopeful in their selection since not much is listed on their website. :(

[Zim Hosein]

Mobil 1 and still use the friction modifier.

Behind using the factory specified 75w140 weight, Mobil 1 was my second choice JustRight, but thus far the only place I can find it available is through Walmart.com! :confused:

[justbob]

Behind using the factory specified 75w140 weight, Mobil 1 was my second choice JustRight, but thus far the only place I can find it available is through Walmart.com! :confused:


Mobil 1 without the use of a friction modifier will cause the clutches to chatter. Been there.

Junk.


Sent from my iThrone using Tapatalk

[JustRight]

Behind using the factory specified 75w140 weight, Mobil 1 was my second choice JustRight, but thus far the only place I can find it available is through Walmart.com! :confused:

I ordered the Mobil 1 and friction modifier from Amazon. It was shipped to my door cheaper than I could have run to town and bought it.

Did I mention I luvs Amazon. At least I used to until he started backing the Hildabeast.

[Zim Hosein]

Mobil 1 without the use of a friction modifier will cause the clutches to chatter. Been there.

Junk.

Your response is why I sometimes ask obvious questions justbob; considering how closely spec our cars are, different results from the same part or fluid varies and helps someone like me made a purchasing decision. Considering the cost of a diff. fluid change, I'm not risking Mobil 1. :confused:

[Zim Hosein]

I ordered the Mobil 1 and friction modifier from Amazon. It was shipped to my door cheaper than I could have run to town and bought it.

While I'm still deciding which brand to purchase, (Mobil 1 is off my short list) I did purchase a bottle of Ford XL-3 from Amazon.com knowing that it is next to impossible to purchase locally, one would think that living in a major metropolitan area, fluids and parts should be easier to come by! :mad:

I have to admit though, that XL-3 stuff has a very strong smell! :eek:

[Zim Hosein]

I've been using Redline 75w/140 since I changed to 4.10's... no problems.

Is this the Red Line 75W140 GL-5 Gear Oil (http://www.redlineoil.com/product.aspx?pid=134&pcid=4) that you personally used fastblackmerc?

[justbob]

Summit has really good sales on Lucas brand throughout the year.


Sent from my iThrone using Tapatalk

[hotford]

Any 75W140 Full Synthetic will do, personally the FORD is what I would go with, all of the MM will need Frition Modifier additive, some other manufactures have the additive already in, look for the GL5 that indentifies its already has the FM in it, either way I would go get the ford one and add it as well.

[Zim Hosein]

Summit has really good sales on Lucas brand throughout the year.

I'll keep an eye on their sales e-mails justbob, thanks for the heads-up! :)

[Zim Hosein]

Any 75W140 Full Synthetic will do, personally the FORD is what I would go with, all of the MM will need Frition Modifier additive, some other manufactures have the additive already in, look for the GL5 that indentifies its already has the FM in it, either way I would go get the ford one and add it as well.

Well I am do for an oil change and multi-point inspection soon hotford and since I'm finding it difficult to find synthetic diff. fluid locally, when I hit the dealer I'll see what they have in stock. I suppose that since our Marauders came w/ Ford fluid and FM, perhaps it's best I just stick w/ the factory recipe. :)

Thanks for everyone's input, much appreciated! :beer: