Final Drive Discussion

[JimmyMac]

Don't you need to press it on and off while you are shimming it?

[Dustin]

Originally Posted by 448hpsti

if youre careful and low miles shouldnt be an issue if youre delicate with the press!

Yeah but I would hate to mess it up in the process and then not have a replacement. And if I'm getting a replacement, I might as well change it for peace of mind. All the little things I'm buying are mainly for peace of mind.

[Nightbringer]

Ooooh they have a 5.13 listed. Want.

[Knickstape]

If I plan on purchasing an innovate supercharger, would 4.56 FD be a good idea in an AT. Would the shorter gearing help or hurt?

[Nightbringer]

Judging by the torque curve of the innovate it'd probably make first a bit useless, but I'd say it'd help overall with how ridiculously long our 2nd and 3rd are. If you've got enough tire under the car it'd definitely help.

[Dustin]

I plan on getting the Innovate kit as well and I just purchased a 4.56 final drive. Like @Nightbringer said, 1st may be a bit useless, but only if you plan on putting your foot to the floor every time you take off. For the other 5 gears, it will be fine.

[Knickstape]

That's kinda what I was thinking. Its something I'll have to think through. Thanks for the quick responses!

[ultra]

Originally Posted by 37

Here's the list I compiled with help from @Jeff Lange describing what all I'd need. Part numbers are on me so if anyone finds an error, please let me know so I can correct the list.

90179-20018 ... Pinion nut
90311-38070 ... Pinion seal
41231-24010 ... Pinion spacer
90366-35133 ... Pinion bearing*
90311-43009 ... Side seals (x 2)
41222-22010 ... Ring gear lock tabs (x 5)
12157-10010 ... Drain bolt gasket
SU003-00122 ... Fill bolt gasket
(listed above) ... Pinion bearing shims
(listed below) ... Diff washers**

*Note 1: Pinion bearing can potentially be reused if you or your shop has the removal tool and your bearing is still in serviceable condition. Replacement is recommended but not mandatory depending on these conditions.

**Note 2: Side washers might be needed depending on the new ring/pinion tolerances. If anyone has any input on this, please add to the discussion.


Diff washers in order of thickness:
90201-52001 ... T=2.58, MARK 01
90564-46014 ... T=2.60, MARK 32
90564-46015 ... T=2.62, MARK 33
90201-52003 ... T=2.64, MARK 03
90564-46016 ... T=2.66, MARK 34
90564-46017 ... T=2.68, MARK 35
90201-52005 ... T=2.70, MARK 05
90564-46018 ... T=2.72, MARK 36
90564-46019 ... T=2.74, MARK 37
90201-52007 ... T=2.76, MARK 07
90564-46020 ... T=2.78, MARK 38
90564-46021 ... T=2.80, MARK 39
90201-52009 ... T=2.82, MARK 09
90564-46022 ... T=2.84, MARK 40
90564-46023 ... T=2.86, MARK 41
90201-52011 ... T=2.88, MARK 11
90564-46024 ... T=2.90, MARK 42
90564-46025 ... T=2.92, MARK 43
90201-52013 ... T=2.94, MARK 13
90564-46026 ... T=2.96, MARK 44
90564-46027 ... T=2.98, MARK 45
90201-52015 ... T=3.00, MARK 15
90564-46028 ... T=3.02, MARK 46
90564-46029 ... T=3.04, MARK 47
90201-52017 ... T=3.06, MARK 17
90564-46030 ... T=3.08, MARK 48
90564-46031 ... T=3.10, MARK 49
90201-52019 ... T=3.12, MARK 19
90564-46032 ... T=3.14, MARK 50
90564-46033 ... T=3.16, MARK 51
90201-52021 ... T=3.18, MARK 21
90564-46034 ... T=3.20, MARK 52
90564-46035 ... T=3.22, MARK 53
90201-52023 ... T=3.24, MARK 23
90564-46036 ... T=3.26, MARK 54
90564-46037 ... T=3.28, MARK 55
90201-52025 ... T=3.30, MARK 25
90564-46038 ... T=3.32, MARK 56
90564-46039 ... T=3.34, MARK 57
90201-52027 ... T=3.36, MARK 27
90564-46040 ... T=3.38, MARK 58
90564-46041 ... T=3.40, MARK 59
90201-52029 ... T=3.42, MARK 29
90564-46042 ... T=3.44, MARK 60
90564-46043 ... T=3.46, MARK 61
90201-52031 ... T=3.48, MARK 31

Thanks for the info.

Curious whether either MFactory or Cusco include the shims, let alone all these little extras, in their gear kits.

If not, plenty of pumpkin-noobs like myself are going to be in real pain when we order these gears and run down to our installers, then end up bouncing back and forth between them and the dealer a few times.

[PantsDants]

Hey guys, I posted a thread here on what's all required for a final drive swap: http://www.ft86club.com/forums/showthread.php?p=1275527

TLDR: You can get all the shims the shop will need from Weir Performance. They sell it for the Lexus IS models, but they work just fine on an 86.

[fooddude]

Has anyone done a 4.88 on an MT yet? I think 4.56 might be too mild and 5+ might be too crazy.. 4.88 MT sounds like it would be perfect for a tad more quickness than 4.56 without being too crazy on the highway cruising.

[DAN_BRZ]

has anyone done this mod yet with a light weight drive shaft?

[JS + BRZ]

Originally Posted by PantsDants

Hey guys, I posted a thread here on what's all required for a final drive swap: http://www.ft86club.com/forums/showthread.php?p=1275527

TLDR: You can get all the shims the shop will need from Weir Performance. They sell it for the Lexus IS models, but they work just fine on an 86.

This is some AWESOME info. Thank you, PantsDants.

[Dipstik-sportech]

Does anyone know if there's a 3.73 or a 3.55 available aftermarket yet?

Sent from, The Frozen North

[diss7]

Originally Posted by Dipstik-sportech

Does anyone know if there's a 3.73 or a 3.55 available aftermarket yet?

Sent from, The Frozen North

The NZDM and JDM RC spec 86s come with a 3.727 FD.