Frosted123

Asked earlier in the "no dumb questions thread" but didnt get a response there. Thought I'd try making a thread for it.

The new 2018 F-Sport IS now come with a LSD standard. Would a direct swap be possible onto a 2014 model?

nan88

iTrader: (1)

Although I dont have any solid info.
The 2018 drive-train should be identical to the 2017.
So it should fit.
My question is, is the LSD purely mechanical?

There was a user on here that swapped a FRS LSD into his 3IS250.

redspencer

iTrader: (1)

It's a Torsen LSD (Type B) that has been used on other Lexus models and is purely mechanical. The differential should be a direct fit.

The FRS/BRZ LSD is not compatible with the 3IS350. I believe you meant to say 3IS250 as the 250 folks have been utilizing this LSD with great success.

nan88

iTrader: (1)

Thanks for the correction, editted to reflect.

Is the 3IS250 drivetrain different from the 3IS350s?
Do they also share transmissions?

E46CT

The 2014 IS uses a different subframe. The mounting points are slightly tweaked. 15+ uses a larger wider mount diff

nan88

iTrader: (1)

So 2015+ should work?

E46CT

Should. hard to say on a platform not many have played with too much. too new. may have to figure it out yourself through trial and error.

Frosted123

Feels bad, but that the price you pay for a first year of a new gen. Thanks for the answer.

Jeff Lange

iTrader: (1)

The 2014-2018 rear differential is the same. The differential mounting points were not changed.

The LSD would be a direct swap for older 3IS350 RWD models.

Jeff

Frosted123

I tried calling my local lexus dealership and they asked for a part number for the Torsen LSD 2018.

I've found this website for part numbers, but am completely lost as to which parts I might need. Would someone be able to help me identify which parts I would need to swap a 2018 Torsen LSD into my 2014 IS?

https://parts.lexus.com/a/Lexus_2018...2430-4101.html

nan88

iTrader: (1)

I've accidentally fallen into another rabbit hole.
It would be one of these assemblies:

41110-24270 - ~$4,5K
https://parts.lexus.com/p/Lexus_2018...111024270.html

41110-30B51 - ~2.8K
https://parts.lexus.com/p/Lexus_2018...111030B51.html

41110-53320 - ~$2.8K
https://parts.lexus.com/p/Lexus_2018...111053320.html

My guess is it would be 41110-24270, but im unsure.
But if you notice the axle mounting pattern between 41110-30B51 & 41110-53320, it is 3 bolts vs 4 bolts.
I believe the 2011-13 IS350 / IS-F / 2IS are 3 bolts and the 2014-18+ / 3IS are 4 bolts, pictures linked.
-Quick edit- 2IS-250s are 4 bolts.

If you want peace of mind, the 41110-24270 looks like its the one.
(Im assuming by price differences in the assemblies, as I dont trust the images provided).
If you want to be potentially the first 3IS with a ISF racing differential or save some money ($2K vs $4.5K), then proceed below.
If you have 2IS-250 or 3IS-250 (AWD confirmed) then a FRS LSD drops right in.

Another option is to do a similar swap like the 2008-2009 --> 2010+ ISF LSD diff's:
OEM swap is above, AE stuff below.

Came across a LSD offered by OSGIKEN LSD that fits in an ISF & IS350 (for 2IS) but unsure about compatibility.
It looks like its better than the torsen diff, but it requires some modifications (shaving) to fit the OSGIKEN LSD.
There was also mention of a ATS LSD.

Might be a good idea to reach out to @redspencer as he has a OSGIKEN in his 2IS, and participated in both threads.
Somebody please do since I currently wont be swapping into a LSD, at this time.

Conclusion: Find out if 2IS350 differential is a same as 3IS-350, so we can fit ISF stuffs.
Another question arises - What in the world does the IS200t use?
I'll probably spreadsheet this in the future, might make another thread for it; where everyone looks at their sticker of their diff.

3IS-250 with FRS LSD (AWD Confirmed, not sure about RWD versions):
https://www.clublexus.com/forums/is-...-15-is250.html

Here's a 2IS diff --> 3IS diff CL thread:
https://www.clublexus.com/forums/is-...swappable.html

ATS Carbon LSD CL thread:
https://www.clublexus.com/forums/is-...bon-lsd-4.html

OSGIKEN LSD CL thread:
https://www.clublexus.com/forums/is-...rite-up-2.html

OSGIKEN LSD - ISF
http://osgiken.net/i-24705810-lsd-lexus-is-f-use20.html

OSGIKEN LSD - IS350
http://osgiken.net/i-24705809-lsd-le...350-gse21.html

Here's an install guide by FIGS Engineering:
http://figsengineering.blogspot.com/...-lock-tcd.html



4-Bolt Pattern - 3IS-250


3-Bolt Patern - 2IS


Simple part swap?


OSGIKEN LSD

Frosted123

I managed to find this thread that briefly mentioned the 3IS 350. If i understand it correctly, the ISF looks fairly similar, but perhaps the best choice is to just figure out which part # the 2018 LSD is.

https://www.clublexus.com/forums/sus...3is-250-a.html

u have a few options here. I cant say it will mount up to your rear subframe because the bushings on the frs is round and the bushing on a is250 is eggshaped but I can tell you this. The final drive is different 4:1 vs 3:7 (oem lexus 250) you can take the frs unit and mount your ring gear and pinion gear to it. or you can take the frs carrier assembly with full guts and bolt it up. for an frs complete differential is a double upgrade, an lsd traction unit and a shorter final drive. the frs uses a is250 transmission with the exact amount of planetary teeth in every gear.. also the frs and is250 uses the same inner cv joint (diff mount) but different outter joints (hubmount). its called velocity type. both frs and is250 uses the same propeller shaft the only thing different is the frs uses a different outer/hub joint while the is250 uses the same velocity style outer shaft.


is350 have a slightly larger ring gear and a few more gear teeth than a 250. also it is a 5 bolt pattern propeller shaft. it wont work for is350.


you can look into is300 carriers for easy in and out swaps and a shorter final drive or use your final drive with a Toyota lsd for is250 owners


is350 owners might have to look further for is-f unit.


I gather up my information from my work computer at a Toyota dealership. I have access to all specs, procedures, illustrations, repair manual etc to Toyota scion and lexus .

-----------------------------------------------------------


ok here.

2006 is350 have a ring gear size 208mm
12 teeth on the pinion gear
49 teeth on the ring gear

is-f torsen diff have a ring gear size 208
16 teeth on the pinion gear
47 teeth on the ring gear

3rd gen is350 have a ring gear size 208mm
15 teeth on pinion gear
47 teeth on ring gear

3rd gen is250 have a ring gear size of 205mm
11 teeth on pinion gear
41 teeth on ring gear

Scion Frs torsen have a "unknown ring gear size" not listed
10 teeth on pinion gear
41 teeth on ring gear

Stamped on Frs diff uses a FD20A but is listed as a FD20AT

is250's should have this stamp, so should the 3rd gen is250. both scion frs and 3rd gen is250 use a 3 piece type propeller shaft(shell cup type) and both share the same inner axle joints constant velocity type(cv type). i think 3rd gen owners are good to go with this one. It should be compatiable with 3rd gen is250.


--------------------------------------------


I've checked another website

It shows the 41110-24270 part number just like in the other website as a LSD, so i believe its this one.

https://www.lexuspartsnow.com/parts/lexus-carrier-assy-differ~41110-24270.html?Make=Lexus&Model=IS350&Year=2018&Submodel=&Filter=(1=2GRF;6=8FC;0=GSE31L-AEZLHA)&Location=rear-axle-housing-differential,,41110

And then i compared that to a 2014 lexus is350

https://www.lexuspartsnow.com/parts/lexus-final-gear-kit-differential-rear~41201-80050.html?Make=Lexus&Model=IS350&Year=2014&Submodel=Base&Filter=(1=4GRFSE;6=6FC;0=GSE30L-AETLHA)&Location=rear-axle-housing-differential,,41201

The FGR are different from the 2018 and 2014 though. Im not knowledgable enough to know what it means,

Jeff Lange

iTrader: (1)

41110-24270 is the complete 2018 LSD, it has a final gear ratio (FGR) of 3.133:1.
41110-53320 is the complete 2014-2018 open differential, it also has a gear ratio of 3.133:1.

41301-53041 is the open differential unit itself.
41301-53051 is the Torsen LSD unit itself.

Relevant Applications:

205mm (4-bolt flange):
2001-2005 IS300
2006-2015 IS250 RWD
2009-2015 IS250 AWD
2013-2019 Scion FR-S/Toyota 86

208mm (3-bolt flange):
2006-2019 IS350
2008-2014 IS F
2016-2019 IS200t/IS300

Final Drive Gear Ratios (North America):
2.937:1: 2008-2014 IS F, 2016-2017 IS200t, 2018-2019 IS300 RWD
3.133:1: 2014-2019 IS350 RWD
3.727:1: 2002-2005 IS300 5MT, 2006-2012 IS250 6MT, 2014-2015 IS250 RWD
3.909:1: 2001-2005 IS300 5AT, 2006-2013 IS250 6AT RWD
3.769:1: 2011-2019 IS350 AWD, 2016-2019 IS300 AWD
4.083:1: 2006-2013 IS350 RWD
4.100:1: 2006-2015 IS250 AWD, 2013-2016 Scion FR-S 6MT, 2013-2019 Scion FR-S/Toyota 86 6AT
4.300:1: 2017-2019 Toyota 86 6MT

Jeff

milimart

Hello,

Who could help me to check does this lsd fits to my is 200t. It’s DREXLER LSD for ISF.

Mesh704

Hello guys

I've just purchased used RC350 F-sport RWD diff. It comes with Torsen LSD. Car VIN attached

I'm going to install it on my 2014 IS350 TwinTurbo