XL3 friction modifier for rear diff - PP?

The manual and Ford recommend XL3 friction modifier for the rear diff.

Why would you need it in the PP Torsen?

Good to go, thanks.

http://www.mustang6g.com/forums/showpost.php?p=1002466&postcount=7

That's just what I was going to say!

Amsoil Severe Gear 85w-90

whatsup62 said:

Amsoil Severe Gear 85w-90

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Are you still using friction modifier with Amsoil severe gear?

isedawishy said:

Are you still using friction modifier with Amsoil severe gear?

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Yes i did when I ran the stock rear with the Amsoil.
With the Wavetrac I am now running I am also using it (figured it couldn't hurt) with Lucus Oil Synthetic 75/120

whatsup62 said:

Yes i did when I ran the stock rear with the Amsoil.
With the Wavetrac I am now running I am also using it (figured it couldn't hurt) with Lucus Oil Synthetic 75/120

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Slightly off-topic, how do you like the Wavetrac? At some point in the future I'll be either getting a 3.73/torsen pumpkin or keeping my gears and getting a Wavetrac/Quaife.

BG 75W140 fuid from OPMustang.com. I do not add friction modifier to my 3.73 Torsen with that fluid because it doesn't need it.

No fluid is going to get rid of the clanks/clunks born from the ridiculous slack in the MT-82 driveline. I do not have much groaning in slow speed, full lock turns with BG fluid - very rare. I did almost all the time with factory fill and I even added more friction modifier to the factory fill and that helped some, but it was still noisy in that situation. I have to make 5 full lock turns in my parking garage at home and would probably have pulled my hair out if I had to listen to that noise for the life of the car... it drove me nuts.

BmacIL said:

Slightly off-topic, how do you like the Wavetrac? At some point in the future I'll be either getting a 3.73/torsen pumpkin or keeping my gears and getting a Wavetrac/Quaife.

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So far I love it...time will tell i guess. Putting some good power through it with sticky tires and has held up great. No more popping noises and just seems to be smoother. I also upgraded to FRPP half shafts at the same time so it might be a combo of the two. Built a entirely new rear with it and Beefcake shot me a good deal on it. Very happy so far.

whatsup62 said:

So far I love it...time will tell i guess. Putting some good power through it with sticky tires and has held up great. No more popping noises and just seems to be smoother. I also upgraded to FRPP half shafts at the same time so it might be a combo of the two. Built a entirely new rear with it and Beefcake shot me a good deal on it. Very happy so far.

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Thanks. Great to know. Do you know if the torque bias ratio is less than the torsen?

FYI. Some/many synthetic gear oils, such as normal Redline include friction modifier and others, such as Ford's and Redline NS (no slip) do not. Many synthetic gear oils indicate on the label or in online documentation when they include friction modifiers. Others do NOT make that clear. For clutch type limited slips, such as the Ford Traction-Lok using something like Redline NS can reduce inside tire wheel spin after the oil and diff get hot. This can be noticeable when making 90 turns from a stop since the inside tire will chirp or otherwise make it obvious that the tire is slipping rather than the diff clutches.

I have no idea what running a Torsen without either separate or "included" friction modifier does to or for the Torsen.

Doesn’t really do anything except a little less noise.