Is Torsen LSD unique to 3.73

Hi, guessing this has been discussed somewhere, but I haven't found it. I'm like many others, researching and configuring my first real sports car. Been busy configuring the GT on Ford's site and it's odd when I preview any of the three gear ratio's 3.31, 3.55 or 3.73 it simply mentions "limited slip rear axle" as the description for all three. Of course when selecting 3.73 I get notified that is required with the Performance Pack. Only under the Performance Pack description is where it Emphasizes its the Torsen type LSD. Of course I have wishful thinking that it's just a marketing ploy to make the Performance Pack LSD sound like its greater than the 3.31 and 3.55 options, which could be assumed to be clutch style. Does anyone know for certain if the 3.31 and 3.55 LSD options are clutch based design versus Torsen, which I'm lead to believe is similar to the Trutrac LSD I have in my other vehicle. Thanks for any insight. Sorry for any run-on sentences.

Only the 3.73 gears with PP have the Torsen diff.

Only the PP has the torsen and it comes with 3.73 gears. I ended up changing my 3.73 gears for 3.31 gears. IMO, 3.31 drive better and are faster but, I do have a SC.

I may change my pp to 3.55 at some point. 3.73 is a little short for a 99% daily driver

evo8904 said:

Only the PP has the torsen and it comes with 3.73 gears. I ended up changing my 3.73 gears for 3.31 gears. IMO, 3.31 drive better and are faster but, I do have a SC.

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Did you keep the Torsen or did you swap out the whole Diff?. Reason I ask is because I want a Torsen in my ECO but also want to keep the 3.31s

evo8904 said:

Only the PP has the torsen and it comes with 3.73 gears. I ended up changing my 3.73 gears for 3.31 gears. IMO, 3.31 drive better and are faster but, I do have a SC.

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Glenn G said:

Did you keep the Torsen or did you swap out the whole Diff?. Reason I ask is because I want a Torsen in my ECO but also want to keep the 3.31s

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X2 on that question. If you didn't change the carrier it means the carrier break is above 3.73 so maybe (just maybe) Ford uses the same Torsen carrier for all the ratios as it would allow them to only stock one type of LSD. I know still wishfull thinking on my part. Has anyone seen any literature stating that the lower ratio's are clutch based. Can you post the info if you have a link?

Anyway, thanks for the replies. Sorry if I'm still not convinced. Maybe someone has taken one apart and seen the two are easily distinguishable, maybe someone could post a pic of the two carriers side by side?

Glenn G said:

Did you keep the Torsen or did you swap out the whole Diff?. Reason I ask is because I want a Torsen in my ECO but also want to keep the 3.31s

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This should answer your question (description) :

https://fordperformanceracingparts.com/parts/part_details.asp?PartKeyField=24733

Glenn G said:

Did you keep the Torsen or did you swap out the whole Diff?. Reason I ask is because I want a Torsen in my ECO but also want to keep the 3.31s

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I kept the torsen.

kz said:

This should answer your question (description) :

https://fordperformanceracingparts.com/parts/part_details.asp?PartKeyField=24733

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It does thanks! For $1150, I think I'll just wait until a few Europeans begin putting GT's in ditches and parts are on ebay.

Glenn G said:

It does thanks! For $1150, I think I'll just wait until a few Europeans begin putting GT's in ditches and parts are on ebay.

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That is over priced. I bought my torsen and had to buy another one. I got a new one for $985. I'm sure that you could find it cheaper.

Bartly, the Torsen will fit with any of the Super 8.8 ratios from 3:31 and numerically higher. It will not fit the lowest (3.08 I think) ratio, as that has a shifted ring gear flange location. Right now, Ford only pairs the Torsen with the 3:73:1 gear set, but that doesn't mean that can't mate it to the 3.55 or 3.31 set if they saw fit. I can tell you from first hand information, straight from the pony's mouth, as it where...

EXP Jawa said:

Bartly, the Torsen will fit with any of the Super 8.8 ratios from 3:31 and numerically higher. It will not fit the lowest (3.08 I think) ratio, as that has a shifted ring gear flange location. Right now, Ford only pairs the Torsen with the 3:73:1 gear set, but that doesn't mean that can't mate it to the 3.55 or 3.31 set if they saw fit. I can tell you from first hand information, straight from the pony's mouth, as it where...

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Thanks Jawa for the info. I went and looked for OEM LSD diffs for the '15 and saw there were two available, one significantly more than the other. Thanks for the confirmation.

EXP Jawa
Do you know if I can remove the Torsen and install a traction Lok?

Changing the rear gear is one way but if you're making significantly more power ie; SCed you might want to change transmissions instead. That is the way I am going. Yes it costs more.

Tremec Magnum XL?