2nd Gen Non-Engine/Transmission Friction Modifier For Rear Differential?

[WMonroe]

I am going to be changing the fluid in my rear diff and was wondering where to get the track-lock friction modifier. Is that something I can pick up at Advanced Auto parts or a similair store or do I have to go to the dealer?

Also I think the dana 80 rear takes 4 quarts how much modifier would go in with that?

thanks in advance.

Will

 

[klenger]

I bought two bottles from the dealer when I changed mine last time, and only used one. I will sell it for $10, shipping included if you are interested. If you are changing to a synthetic, check for clutch binding before you add the modifier. The first time I used Amsoil, I didn't need any modifier; the 2nd time I need one bottle to get rid of the chatter. If you add too much, it makes the LSD useless.



Ken

 

[illflem]

No set rule

The amount of wear on the differential clutches is what makes the difference on how much if any modifier is needed. Doesn't matter which kind of oil you use.

 

[Turbo Thom]

If you have a Carquest close by, they have a friction modifier in a tube. I used a tube in my rear end (truck) and it worked well. I just bought 2 bottles from the dealer and noticed it doesn't have the smell I'm used to. The stuff I got from CQ did have the odor. This time I use the 140 Amsoil and I did need one bottle. Felt like the 4X4 was engaged when I would turn. All is well now.



. . Preston. .

 

[mberry]

I used Royal Purple. It already has the correct amount of friction modifier in it and I didn't have to do anything else. Just my $. 02 worth.

 

[DDT]

I used Royal Purplefor the same reason. So far all is well.

DDT

 

[Motorhead]

I third on the Royal Purple... Great product. Not only do you NOT have to add the friction modifier, you are putting in a synthetic oil that is much better. I think you need more than 4 quarts. I bought 5 for a Dana 70.

 

[fortunate1]

Older axles are already "friction modified" (?)

I changed my rear end oil recently just to make sure that there wasn't any salt water in it. There wasn't. I didn't have any friction modifier, so I didn't put any in. With the Mag-Hytec the capacity is up to a little over a gallon. I've driven almost 2000 miles since then; no chatter, no problem. I know that I do still have "limited slip" also - two black stripes down the street confirm that.

 

[WMonroe]

Thanks for the replies everyone. I changed the front and rear diffs tonight. Everything went really well. The rear though only took about 4 quarts plus the friction modifier, I guess once the axel tubes fill back up (i drained them also) I'll have to add a little more. The owners manual said to use 5% friction modifier so thats about how much I used. Drove it once already tonight and everything "seems" normal. Will have to try the limited slip to make sure. Again thanks for all the information.

Will

 

[Trizae]

the stuff from the dealer will loose it's smell as it sits on the shelf,,,,,, i have noticed that over the years

 

[John]

They changed the formulation of the Mopar friction modifier several years ago from that REALLY nasty smelling stuff they used to offer.

 

[Challenger-II]

From what I understand, most do not have to add any FM to Amsoil either. I know I didn't add any. When exactly does the rear chatter if you need it? Will figure 8's in a parking lot at low speed make it chatter if FM is needed? My rear will chop a little when accelerating to turn a corner on wet roads. Someone please explain for those in the dark. Thanks