I was reading this post under this website http://www.miata.net/faq/99central.html
I have a NC22-NAA which looks like I have a TorsenII? I am guessing. I have a 99 Sport Bose radio Nardi steering wheel and tan leather tan top.
How do I tell if my NB came with a LSD?
For 99-02 the quick method is to check the Model # against these lists (US). Your cars model # can be found on the Vehicle Information tag in the passenger door jam (lower left corner of tag).
Mazda stopped installing this tag mid-year 02. Most if not all 02 SEs do not have the tag.
1999 2000 2001-02
NC11 NC50 NC73
NC12 NC51 NC74
NC14 NC52 NC75
NC17 NC55 NC76
NC18 NC58 NC78
NC20 NC59 NC79
NC22 NC60 NC80
NC23 NC63 ND22
For 02+ cars without the ID tag, see the answer to the next question.
I'm looking at buying an NB and it doesn't have or I don't have access to the Model #. How can I know if it has a LSD?
For 1999 (Torsen II):
If the car came with cruise control, power antenna, windblocker and power door locks and/or tan leather interior/top, it has the LSD.
It it is a 10th Anniversary Edition (10AE), it has a LSD.
If it is a Sports Package, it has a LSD (see How to ID a 1999 Sports Package below)
For 2000 (Torsen II):
If the car is an SE or has tan leather/top and Bose Stereo (Miata LS), it has a LSD.
If the car has factory 15" wheels and the (99-00) STB in the engine compartment, but doesn't have power door locks and cruise control it has a LSD
For cloth interior cars with 14" wheels, if you can't get the Model #, then you will need to have the VIN # and phone Mazda Customer Service, asking them nicely to check what options were on the car as delivered.
For 01-02(Torsen II):
If it is an SE or has a tan leather interior/top and Bose Stereo (Miata LS), it has the LSD.
If it has a cloth interior with 5sp, factory 16" wheels and has the factory STB (see pic) but doesn't have power door locks, cruise control and remote keyless entry, then it has the Suspension Package option (see 01-02 HARD S) which included a LSD.
01-02 Miata (cloth interior, 15" wheels) could get a LSD as optional equipment. There is no way to visually tell if it has a LSD. But if it doesn't have power door locks, cruise control and remote keyless entry it can not have the LSD. Mazda required that the Convenience Package be ordered at the same time as the LSD. If the car has the Convenience package (possible LSD) and you can't get the Model #, then you will need to have the VIN # and phone Mazda Customer Service, asking them nicely, to check what options were on the car as delivered.
For 03 (Tochigi Fuji):
If the car is an LS or SE (leather, Bose Stereo, Silver interior trim) it has a LSD.
If it's a Shinsen Version (Titanium Gray Metallic paint, dark blue cloth top and blue cloth seats)it has a LSD.
A LSD was available for the black cloth interior models. They could have a LSD if the car was ordered with the Suspension Package option (see 01-02 HARD S) but a LSD could also be ordered separately.
Best bet is to get the VIN and call Mazda Customer service.
For 04-05: (Tochigi Fuji):
If the car is an LS (leather interior, Bose Stereo, Silver interior trim) it has a LSD.
A LSD was available for the black cloth interior models only if it was ordered with the Suspension Package option. Unlike the previous years it could not be ordered separately. Unless you can see the car up close and know exactly what to look for, it's very had to tell if an 04-05 was order with the Suspension Package. Again, best bet is to get the VIN and call Mazda Customer service.