differential fluid change

[kil roy]

just finished up my gear oil change

to the royal purple.



first observation: is that ford did not put a flat magnet

in the bottom of the diff case, i thought this was strange

as the dodge i had and my friends chevy had them.

the magnets in those diff's, where positioned, caught all the metal

that had worn from the gear set.



second observation: is that my differential was not full.

whether it had been serviced at some time i have no way of knowing

as second owner did not give any maintenance records.

the rear is not leaking anywhere that i can see and the axle seals

have no visable leaks/weepage and i had one hell of a time removing

the fill plug.

i actually used my 3/8s breaker bar, hammer and my small hydraulic jack.

i jacked up on the breaker bar then gave it a crack with the hammer and

it finally popped loose.



third observation: and the most important is that the truck

felt smoother, i mean all i did was drive around the block

after changing and the real test will be tomorrow going to work

but it just felt different as in "more firm and quiet"

maybe it was just my imagination but thats how it felt.



now i have to do the front diff and the trans and all maintenance will

be caught up.

 

[Todd Z]

Just did the Adren drive train fluids, It got Mobil 1, it is amazing how much smoother and quieter it is with new fluids... I just cant see driving 100K miles before changing them....

The adren is at 60K..



Todd Z

 

[Rodger Tellefson]

Put RP in our about a year ago, and can not figure out why I did not do it sooner. I actually got one more mpg just by change the rear diff. to Royal Purple to make it a triple play; engine, tranny and diff. Remember that if you have LS you must add the friction modifier.

 

[Chris Joyce]

Is changing the differential fluid something I can do myself or a mechanic? Is there a project on this or is it self explanitory?

 

[Dingo]

Rich, get the diff magnet from FilterMag. They have great products and great service.

 

[Rodger Tellefson]

joycie,



I just checked the Projects/Maintenance and did not see a project on it. You could probably do it yourself. I had mine done at the same time I had taken it in to have a few other things done, and to avoid having to take the fluid to a recycle center. I also put a Trick Flow diff. cover on it as well. You just have to make sure you use 25 lbs. torque. Do a search and you'll find that you do not use a gasket, but there is if I recall correctly a sealant you can use.

 

[Johnny O]

Is changing the differential fluid something I can do myself or a mechanic? Is there a project on this or is it self explanitory?

Depends. The rear isn't too bad to do yourself, the front is virtually impossible. Here, the Valvoline Quicky-Lube will suck them out with a pump and refill with Valvoline synthetic for $39.99 each, so it really isn't worth my time to do it myself.

 

[Alan Peters]

The rear is easy, but I agree the fronts is near insane! Mine was leaking under warrenty but just changed it out a couple of weeks ago. Big difference! Make it part of your normal maintanence schedule, say every 50K or 60K.

 

[Jeff C]

Why would you not use a gasket? Or a combo of gasket/rtv? Also, what weight do you use for the 4.10 LS and is the friction modifier only available from Ford? We have generic stuff at work, but I'd rather spend the few extra $$$ and get the right stuff.



Only reason I ask is because I've never changed it before, and I plan on getting the Ford Racing 8.8 cover, and refilling with RP (just picked up motor oil in RP for my next change) and I want to go RP all around...

 

[Rodger Tellefson]

Jeff, That is what I read here, and just did a search and found what I was looking for.



re: Differential service by svt,4/18/2006 02:21 ET



I've done it myself. It is not too difficult but there are some pitfalls. The fill hole is a little difficult to get to on a creeper. It uses a square plug that can be undone with a 3/8" extension. There is some kind of thread sealer/locker on it. There is no paper gasket on the differential cover. A sealer is used instead of a gasket. I used the wrong kind and it leaked a weak later. That meant doing it a second time. Since there is no drain plug, I didn't want to resue the oil for fear of contaminants. So I bought all new fluids. I forgot the kind of sealer that worked - it wasn't the one from Ford, but that should have been the one I used. Anyway it was a learning experience and made me a better mechanic. Even doing it twice, I saved more than half what a dealer charges. I did it on a time bases (5 years) rather than mileage. It certainly didn't need it based on the visual.

 

[kil roy]

joycie,



I just checked the Projects/Maintenance and did not see a project on it.

too bad i didnt think to check for a project before changing mine or i would have written one up for posting.



its relatively easy but only if you have the right tools.



i used my 3 1/2 ton jack

2 ton jack ( as stated above it was needed to break the fill plug free)

2 jack stands

3/8s breaker bar

3/8s ratchet (i used my air ratchet, made the job much quicker)

13mm 6 point socket ( i dont like the 12s to easy to round off a bolt)

gasket scraper

torque wrench

carb cleaner and rags ( needed to wipe the cover and housing clean)

new felpro gasket ( yes, they do make a gasket)

some permatex brown to insure seal ( good enough for airplanes good enough for me)

3 qts royal purple in weight you need ( you need about 5.5 pints of it)

1 container of posi additive

1 5qt drain pan

optional step is some paint or undercoating, when i clean the cover i like to repaint it

before reintalling.



with all that it is a really easy job and the only thing i recommend is to

break the fill plug free before pulling the cover because if you cant break it

loose you wont be able to refill it once drained.

 

[Todd Z]

The Aluminum covers come with a new paper gasket. I have used that with a thin coating of RTV....



Ebay has an awesome gasket that is metal coated with rubber. I bought 2. 1 is on the adrenalin already and the TRW rear diff girdle I bought will get the other....



Jeff use the 75-140 syn or the 85w140 and the FORD additive.... I have had the best luck with that combo...



The front diff for those with 4WD gets 80-w90 syn, no additive...

Todd Z

 

[Craig Long]

Is the additive for LS only? I have an open rear, would I need the additive?

 

[Bill Ellis]

No additive for open dif. Only needed for LS.

 

[RAUL AGUILAR]

Where can i get the rear diffefential cover with cooling fins like someone on here has?:huh:

would it help with temp. while towing?

 

[Eric Pennal]

I got a Mag-Hytec from offroadunlimited.com for $228. It has a magnetic dip stick and drain plug. It also provides increased fluid capacity, and comes with an O-ring gasket.



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