Hello, My first post!
I have an 04 Ford Ranger 4x4 3.0 5sp. It has 50k on it and in great shape. I think its time to change the front and rear Differentials. Could anyone walk me thru these steps? Any suggestions on gear oil type? I have put Amsoil 75W90 in my wifes Forester, and runs great. Will
I need a new gasket on the rear? I dont think there is any any other way to drain, just from the rear cover. How much fluid should I buy to change both. Any other hints would be greatly appreciated. I try and do these things myself, not a mechanic, but with labor prices thru the roof and a kid in college, I must save where I can! LOL!

Thanks for your help in advance!
Mark.......

 

How much you will need depends on the size of your rear axle. Your vehicle's manual will specify. I honestly think you will be fine for another 25k miles, but I might be wrong (its never a bad thing to change your fluids lol)

A lot of guys buy RTV. Its a gasket-forming goo stuff that you re-seal your differentials with. You can loosen the bolts on the rear differential cover, and crack it open. The fluid will drain out. OR, you can buy a hand pump and pump the old fluid out through the fill plug. This will save you from buying a new gasket, or the mess from the RTV. Beware, the fill plugs usually take a hand grenade to break loose, so dont strip the nut.

There are a lot of walk-throughs on the internet. Search around.

Maybe somebody will chime in with more info.

 

For the front I would just use a hand pump to drain. To pull the cover is a bit more work on the front. Fill with 1.7L (3.6 pints) of 80w90 gear oil.

For the Rear.

Removal


Remove the bolts and drain the lubricant from the differential housing.
Remove the differential housing cover.



Installation

The machined surfaces on the differential housing and the differential housing cover must be clean and free of oil before applying the silicone sealant. Cover the inside of the rear axle prior to cleaning the machined surface to prevent contamination. Clean the gasket mating surfaces.
CAUTION: Install the differential housing cover within 15 minutes of applying the silicone, or it will be necessary to apply new sealant. Apply a continuous bead of silicone sealant to the differential housing cover.



If possible, allow one hour before filling the axle with lubricant to allow the silicone sealant to cure. Install the differential housing cover.

Position the differential housing cover.
Install the bolts.
Tighten to 45 Nm (33 ft. lbs.)



Service refill capacities are determined by filling the rear axle to the level shown. Fill the rear axle with of rear axle lubricant and install the fill plug.

Tighten to 52 Nm (38 ft. lbs.)



Fill the rear with 2.4-2.5L (5.25 - 5.5 pints) of 80w90. You may have a L/S rear end which would require friction modifier added to that. Some gear oils like the Mobil 1 synthetic have the modifier mixed in the oil.

To determine which rearend and if you have a L/S use this link.
http://www.therangerstation.com/tech_library/Axles.html

 

Wirelessly posted (Timberwolf)

^^^^this should be a sticky.

 

just did this to my 03 4x4 and i called ford to see how much lub i needed and they said that the front and the rear of all the rangers needed the friction modifyer

 

Straight from Ford Shop Manual. Only states need of friction modifier on Traction-Loc rears. So if you dont have limited slip ya dont need it.

Differential Fluid Type

Front Axle Motorcraft SAE 80W-90 Premium Rear Axle Lubricant

Rear Axle
Except FX4 Level II Motorcraft SAE 80W-90 Premium Rear Axle Lubricant
FX4 Level II Axle Motorcraft SAE 75W-140 Synthetic Rear Axle Lubricant

Add 4 oz (118 ml) of Additive Friction modifier XL-3 or equivalent meeting Ford specification EST-M2C118-A for complete refill of Traction-Loc rear axle.

 

If you dont have a limited slip, you dont need to change the oil. The reason being that your oil doesnt get dirty and it doesnt get hot enough to break down.

Pull your plug, clean the magnet on the plug off, top it off and call it good. Unless you have a seal that is shot, or a bearing that took a digger theres nothing that can contaminate your oil.

 

I have to differ with you on this.
Differentials can get quite hot. As they cool they will draw in damp air which will cause condensation , until they heat up again. This serves to contaminate the oil.

 

Hello, first Thanks for all the tips! What would be the best choice in fluids for gear oil, Stock Motorcraft or something like Mobil ! ? I dont want to waste cash, but dont mind spending it if needed. Are they ok to add togehter stock and syntheic?

Also changing the 5 speed manual tranny fluid, Motorcraft Mercon is no longer available, so what would you recommend using? It clearly states in manual, DO NOT MIX MERCON WITH MERCON V! What about any quality aftermarket Mercon? I know certain transmissions are VERY PARTICULAR on the fluid they need, so I dont want to make a bad decision.

THANKS, Mark....

 

Wirelessly posted (Android)

Hmm I think I used Lucas atf for the tranny. Lucas 80w90 for the front dif and I have Mobil 1 75w90 synthetic for the rear.

 

Find a farmer with an old tractor and ask them when the last time they changed their diff fluid was. More then likely the answer will be never. On my buddys farm they have a ford tractor from 1939 and its never had the diff fluid changed. Its been used all its life and is still trucking today (It pulled me out of a stuck once).

I would also bet that most of the members on here have never changed their diff lube.

 

You are comparing apples to oranges. Tractor lube systems are different from trucks.
I have had trucks that never had a diff oil change in 200 k miles . that doesn't mean the oil was still good.
I'm not trying to get into a pi$$ing match , some people feel the need to change diff oil by the book, some know it's not always necessary.
But how do you know that the OP or others reading this did not submerge their axles in water for any length of time , allowing the diff fluid to get contaminated ?
Different operating conditions require different levels of maintenance .