How to add friction modifier to differential

The soluble chains form dense mono layers or thick reacted viscous layers. In this video we illustrate how to identify the different Ford Differentials and which ones require friction modifier to be added to new fluid when servicing.

Discussion Starter 1 Aug 19 2010.

How to add friction modifier to differential. I know this differential has limited slip but not sure if I need to add modifier or not. I have the diff e-locker. The service manual only states to add only synthetic 75-140W oil.

No mention of any friction modifier. Thanks Guys and Gals Any help would be greatly appreciated. Differential fluid change and the addition of friction modifier.

So as I stated in an earlier thread I decided to change my differential fluid last Friday while I was changing my transmission fluid. Being the Viper noob that I am I thought all I had to do was fill the diff back up with my Pennzoil 75W-140 and call it a day just like all of. Yes on type f.

Add 175-2 oz with stock diff cover drive it and add more as needed. You cant take any out so a little less than first and adding more as needed is a better policy. Organic friction modifiers have long soluble chains and a polar head.

The polar head attaches to the metal surfaces. The soluble chains line up beside each other much like fibers in a carpet. The polar heads may be comprised of phosphoric or phosphonic acids amines amides or carboxylic acids.

The soluble chains form dense mono layers or thick reacted viscous layers. These layers shear easily and create a. Ford recommends that you use SAE 75W-140 GL-5 synthetic gear lubricant with 8 oz of friction modifier Ford Part C8AZ-1B546-A for your 1025 rear axles.

Since you used the Lucas gear lub that has friction modifier included you may not need to add the Ford friction modifier. To be sure I would suggest that you call Lucas and ask them. The amsoil 4oz additive says treats 2-4 quarts.

I put 12 quart 75w90 in dumped 2oz. In with the other half. Took a small amount from another bottle and it was full.

Would like to make this info easier to find since I didnt have any luck with a straight answer. Friction Modification is the newer term for friction reduction To increase the friction coefficient of a fluid you simply REDUCE the amount of Friction Modifier that you add to the fluid. Likewise to reduce the coefficient of friction of a fluid you.

Friction modifier should be added until the chatter in a tight turn goes away. There is usually a spec given for how much to add but Ive found that this can be right or wrong some vehicles work perfect with the spec amount others need twice as much. On these trucks I have seen upper and lower ball joints wear out factory lowers can be shot.

All differentials use gears bearings and shims. Limited-slip differentials have additional clutch packs. Since there is nothing in any differential that is not in a limited-slip differential there should be no harm in using a friction modifier in a non-limited-slip differential although there is no need for it.

If there isnt a problem you dont have to do anything. If there is add only 2 oz. Of the friction modifier at a time.

Its not a good idea just to add the full 4 ounces if the fluid that youre using has the friction modifier added. I dont know of anyone that has had a problem using fluid with the friction modifier added. Drive in figure eights around the parking lot.

Listen for grumbling from the rear end. 3 If you dont hear any then you dont need more friction modifier. So fill up the diff with lube and button it up.

4 But if you hear the racket then add one ounce of friction modifier then repeat step 2. If you have a car with a rear that chatters add a bottle of friction modifier drive the car several miles at speed to warm up and thin out the oil then do a handful of figure-8s in a parking lot to work the friciton modifier into the clutches. Now let the car sit overnight for the new oil to soak in.

If you DO NOT have limited slip you DO NOT have to add any frication modifier but if you DO have limited slip you will have to add some of the Ford Motorcraft Additive Frication Modifier XL-3. Ford recommends adding 4 ounces of it but I would start with 2 ounces and add some more if needed. I always just got a bottle of Fords friction modifier and dumped the entire bottle into the rear end.

Probably too much but they run nice smooth. Even on a modded F150 clutch type 88 alternate frictions steels rather than stacking one or the other like they come from the factory. That LSD was a REALLY tight setup with the HD S spring.

3 Sep 19 2004. Its my understanding that the Rubi differentials are gear based. What that means is that you wouldnt use a friction modifier additive.

In the factory traklok differential or any other clutch-based limited slip you would use the additive to decrease the chatter of the friction clutches. I have gotten varied answers on whether to add friction modifier to rear diff when changing fluid out. 2012 3500 SRW anti spin rear axle i have been told by 2 different dodge mechanics yes add the additive.

But reading thru these various forums i read yes and no. Im changing out both diffs tomorrow with amsoil 75-110. Someone must have a definitive answer THANKS.

Friction modifier additives affect the frictional properties between two rubbing surfaces. They prevent scoring reduce wear and noise and can help to prevent micropitting in industrial gear lubricants. Friction modifiers are commonly used in gasoline engine oils.

Discussion Starter 1 Aug 19 2010. New to the Duramax world got 2006 2500 HD 3 days ago. I read a lot of threads but I am used to working on Camaro Corvette etc.

Those cars need a friction modifier in the rear end so the rear end does not. I have read different posts and see that its a common issue and to add more spicer friction modifier. They drained the rear and pulled the cover and removed the posi unit for inspection.

It had some surface rust on the new friction plates and the clutches looked fine. It is now capped up and we used conventional 80w90 diff oil. In this video we illustrate how to identify the different Ford Differentials and which ones require friction modifier to be added to new fluid when servicing.

The friction modifier I used required one bottle per 2qrts so I added 15 bottles. Took her out for a test drive and started nice and slow. I did hear a groan at first but it went away the more I drove I figured the friction modifier had to mix up with the gear oil.