Just dumped 5.5 quarts (!) of Mobil 1 into my newly-Mag-Hytec covered diff. I did not add any friction modifier. Is it required with the Mobil 1? If not required, will it hurt to put it in anyway?

If I need to add the modifier, where is the most convenient place to get it? Please don't say the Ford dealer--I have never seen anything convenient about a dealership.

Thanks,

 

Tim, I d/k but TTT

Dan

 

yes you need to go to the dealer if you want the stuff....

BUT... you don't need it. Your traction lok differential will actually work better without it. It is only there to prevent noise and such, it actually makes the clutches slip which you don't want. Besides with the synthetic oil you shouldn't need it anyway.

As a side note I'd recommend (as do alot of gear manufacturers) staying away from synthetic oil in your axle anyway, but that is another story.

another side note, you truck already comes with Ford synthetic 75-140 gear oil, why are you changing? <edit: nevermind, I see you said you put on a new diff cover>

later,
chris

 

Yes, put it back in. It will take two bottles with the added capacity of the Mag-Hytec. I just put one of these on and if I do say so myself they are a great looking peace.

 

i'm about to change mine as well... i didn't know that about the friction modifier stuff...

 

if you were overhauling the rear and replacing clutches, then you'd need to soak them overnight in friction modifier and add some to the new fluid, but frankly if you are just changing the fluid as routine maintenance, and especially using synthetic oil anyway, I wouldn't bother adding friction modifier at all.

later,
chris

 

Please comment on whether the extra support/capacity helps with the 50 - 60 mph whine that ford says is a characteristic of the F150 .......... looks alone is outstanding!!

 

(1) I have never heard the whine (but I don't drive 50-60 )
(2) Looks--yeah, baby:


Shows the QA1's, Hotchkis bar, and So-Cal adjustable links. Ruslow panhard (mount already attached to diff cover) and foam bump stops coming next.

 

You will know you need it if you feel a slip or hear a chatter taking off in a slow RH or LH turn. I did and any good driveline shop should have it in stock. About 8 bucks a bottle.

 

Pep Boys sells the friction modifier... comes in a tube (I was looking for a bottle).

I put 2 in when I installed my Mag Hytec earlier this year.

 

Mobil1 contains the proper additives already. You do not need to add any additional, although Mobil1 will say that if your manual recommends it to use it.

 

ordered another stock diff cover today ($20).
gonna have it powdercoated, then change the fluid out..

what gear oil do we use? the manual says one thing, and the tag says another.. (so i've heard)

i'll prolly go with the mobil1 oil.. do i need a pump to get it in there?
what do i retorque the bolts to?
i've got some black RTV, will that do as a gasketmaker?


thanks!

 

I've had that problem since new. Any suggestions?

 

clonetek, you can actually use either, but if you use what is stated in the SVT Supplement then this lighter weight will yield you additional performance.

 

hmm.. interesting...