I believe you have to use the SER tranny but i dont know if the bluebird was a AWD though...I think so....but u use the Sentra tranny..beacuse they (the GTIRs and aveniers????? i dunno about the bluebirds) are AWDs..... ...but those have LSDs....the SERs...the SERs i always find are more expensive +2k...I love my B13 sentras and G20Ts man thats the 2nd option...I guess I just liked 240s for sooo long...but who knows...I dont even 100% know yet... Glad to see that I am not getting hurt yet....