Ford Diff Additive

Terryhauler · #1 (**permalink**) 04-10-2005, 09:25 AM

What's up with this????

I went to the dealer yesterday to get rear diff oil (LSD) for my truck & he came back with the LSD oil & this 4 oz bottle of Motorcraft (Ford) "friction modifier"

. I said what the heck is that for. He claims that they put it in all LSD rear ends and it's highly recommended. Ford is the only company that makes it. Cost $12.00 cdn

Have you ever heard of this?? Seems weird to but Ford stuff at a Toyota Dealer.

fastone01 · #2 (**permalink**) 04-10-2005, 12:23 PM

I have always use the ford LSD Fiction modifier on all my vehicles that have LSD.

When I got my LSD for my truck, I talk to both the place I got mine and West Coast differential CA. Both recommended to use the Ford Friction modifier. I have done this on my 72Celica, 73 Corolla for the past 19 years and LX 470 and the tundra for the past 4 years. No issues!

I just drop the diff oil yesterday on the tundra and use Mobil1 syn 75/90w with 1 bottle of ford LSD modifier. Got 2 bottles at ford for 4.29 a piece. 4 oz bottle and they are now blue. It use to be reddish tan.

Hope this helps.

Quote:

Originally Posted by Terryhauler

What's up with this????

I went to the dealer yesterday to get rear diff oil (LSD) for my truck & he came back with the LSD oil & this 4 oz bottle of Motorcraft (Ford) "friction modifier"

. I said what the heck is that for. He claims that they put it in all LSD rear ends and it's highly recommended. Ford is the only company that makes it. Cost $12.00 cdn

Have you ever heard of this?? Seems weird to but Ford stuff at a Toyota Dealer.

Terryhauler · #3 (**permalink**) 04-10-2005, 01:57 PM

Thanks...........I was just curious about this. Your right it's blue. I wonder if I could get it cheaper at Ford.

I like to change the diff fluid every spring. I've had it done at the dealer in the past, this is the first time I've done it myself.

KLS · #4 (**permalink**) 04-10-2005, 02:26 PM

Most differential gear oils already contain the LSD friction modifier and do not require more. Here's what Mobil 1 says, "Mobil 1 Synthetic Gear Lube LS 75W-90 contains special friction modifiers designed for limited slip-type differentials. In most applications, the addition of special LS (limited slip) additives is not required. For axles requiring the highest level of limited-slip performance, OEM specific LS additives can be added to this fluid."

Read the label on the gear oil. If it says that it is OK for LSD, try it without any extra additive. If you get chattering, add a part of a dose. Too much additive will result in the LSD clutches slipping.

The LSD addtive is sold under many labels. My Eaton/TRD LSD unit came with a tube of Sta-Lube brand. It all works about the same unless the maker of the LSD unit specifies something unique. I use Schaeffer GL-5 gear oil which already contains the addtive and use none extra. I have no chattering and good LSD operation.

Ken

fastone01 · #5 (**permalink**) 04-10-2005, 11:38 PM

Your Welcome. I drop my gear oil yesterday and I was pretty shock to see the diff oil darker than expected after 32K.

I think I might just do the same interval you are doing every spring with synthetic diff oil especially now that I am towing.

Quote:

Originally Posted by Terryhauler

Thanks...........I was just curious about this. Your right it's blue. I wonder if I could get it cheaper at Ford.

I like to change the diff fluid every spring. I've had it done at the dealer in the past, this is the first time I've done it myself.

pcosens · #6 (**permalink**) 04-11-2005, 11:42 AM

Quote:

Originally Posted by Terryhauler

What's up with this????

I went to the dealer yesterday to get rear diff oil (LSD) for my truck & he came back with the LSD oil & this 4 oz bottle of Motorcraft (Ford) "friction modifier"

I posted this before, I'm sticking w/ Toyota brand LSD fluid and Ford friction modifier as was STRONGLY recommended by Toyota techs:

==================
This is clipped straight from the Eaton site FAQ:
==================

Q - What type of lubricant and limited slip additive should I use with my newly purchased Eaton Limited Slip Differential? [ed: factory Toyota LSD??]

A - Eaton strongly recommends utilizing an API-GL5 approved Mineral-Based 80W-90 Axle Lubricant and one 4-oz bottle of Limited Slip Additive (GM or Ford).
==================

I use synthetic everywhere else.

P

rakent · #7 (**permalink**) 04-12-2005, 09:38 AM

Quote:

Originally Posted by pcosens

I posted this before, I'm sticking w/ Toyota brand LSD fluid and Ford friction modifier as was STRONGLY recommended by Toyota techs:

==================
This is clipped straight from the Eaton site FAQ:
==================

Q - What type of lubricant and limited slip additive should I use with my newly purchased Eaton Limited Slip Differential? [ed: factory Toyota LSD??]

A - Eaton strongly recommends utilizing an API-GL5 approved Mineral-Based 80W-90 Axle Lubricant and one 4-oz bottle of Limited Slip Additive (GM or Ford).
==================

I use synthetic everywhere else.

P

I'm still very curious as to why both Toyota and now apparently Eaton stress conventional gear oils in either straight 90 weight or 80W-90 for the limited slip rear differentials. It can't be a cost issue, because Toyota puts a synthetic 75w-140 oil in its open rear ends.

There must be some reason why a synthetic 75W-90 or 75W-140 oil doesn't work well with the LSD's.

Can anyone shed any light on this?

papayasalad2002 · #8 (**permalink**) 06-18-2008, 05:41 AM

This is a helpful thread. I replaced my 05 Dcab rear dif fluid with Mobile1 75-W90 LS fluid and the rear end is getting the shudder/slipping noise, whatever it's called. Only happens when cold and pulling out of driveway. I attribute what's happening to the Dif fluid change since it didn't happen prior to the fluid change.

Going to add some of that Ford lsd modifier this coming weekend. Hope it works out. Thanks.

cleanb13 · #9 (**permalink**) 06-18-2008, 09:13 PM

I currently work at a Chrysler-Dodge-Jeep dealership and I use the Mopar friction modifyer all the time. I don't get any chattering around corners and use synthetic fluid as well. When I worked for Nissan, they would stock the Mopar stuff too. The Mopar part number is 4318060AB. They come in 4oz containers.

HOGWILD · #10 (**permalink**) 06-25-2008, 04:17 PM

I used 75W90 Mobil 1 in my rear LSD and it made noise that a dry power steering pump would make"LOUD" growl!!, all it needed was a shot of modifiers but dealership just drained it and put 80W90 with modifiers? I called Mobil 1 before i changed my LSD fluid to double check and he said no extra modifiers needed which was "BS" ! Myself would go with Torco Modifiers, they have one specd for Toyota! at 60K service i will go Mobil 1 once again but add the Torco Modifier when i do the change and see if the noise comes back!

papayasalad2002 · #11 (**permalink**) 06-26-2008, 03:20 AM

After reading this thread and the post I made above I went out and bought the lsd modifier from ford $5.99 plus tax. It came in a small bottle.. it think it was only 4 oz... (super stinky stuff!!!) Squeezed that stuff in with the nozzle that came with it and my rear end noise is gone!!! If I didn't read this post I might have took it to the dealership and be down couple hundred bucks. Thank you.