13BstreetportFB

sorry for the stupid thread but i need some solid information... i have an 84 gs and i want to upgrade my pumpkin (3rd member) to a GSL-SE which has LSD 4.08 gears STOCK. BUT i heard that my axles will not fit.. is this true??? 84 gs axles will not fit on a GSL-SE 3rd member??? my main concern is the gears and LSD... i don't care about the discs because i don't have time to swap the WHOLE REAREND and the cables and the brake lines... this car is my daily driver and i just wanted to have a lil bit more torque... i also heard that the 84 gsl automatic transmission comes with a 4.08 3rd member??? is this true as well??? will an 84 gsl 3rd member fit wit my axles??? the gsl just changes my set-up to LSD but no gear upgrade right??? so does that mean that the GSL-SE rearend is not compatable with any other rearend?? i'm very confused and i need someone else who is highly knowledgeable and educated the FB differentials. I JUST WANT TO CHANGE THE 3rd MEMBER to 4.08 gears with LSD WITHOUT CHANGING THE REAREND!!!

Midwest 7's

iTrader: (4)

**** dont make me go to my garage and pull apart my se rear end.
i have always believed it wold be a strait swap but have never done it personally.
the axle spline count would be the difference.
if someone can confirm an se axle is 26 spline i'd say your good to go.

Siraniko

iTrader: (13)

GSL-SE 3rd member will fit on any 84-85 without any mods. They have the same # of splines.

What other parts do you need for your 84. I may have them and install is available by appointment only.

spoolin

pulled from a page i was researching some stuff on a long time ago:

but odds are, you will have the large axles and it should be no problem

13BstreetportFB

can anyone confirm if my axles 84 GS axles will fit on a GSL-SE 3rd member??

spoolin

there's two of us that are 99.99% sure it will work. you will be the only one to confirm it when you do the swap. feel confident in what we are telling you that it will be NO problem.

Hyper4mance2k

iTrader: (40)

I am 100% sure it will work
79-83 small axles all models
84-85 big axles all models

79-82 big pinnion flange all models
83-85 small pinnion flange all models

13BstreetportFB

i know mazda made the bigger axles in 84-85 but its just that a lot of rx7 shops sell two different types of axles for 84-85... one part number for the 12a axles and a different part number for the 13b axles...

trochoid

iTrader: (6)

Sure, because they have a different wheel bolt pattern. Listen Wacky and take him up on his offer.

Siraniko

iTrader: (13)

hell yeah, my rates are the cheapest in town but I do quality work. But again, my low rate requires a 12-pack of cold heine's per visit. Ask DoLuck.

-=DanK=-

I have an 84 GS with a GSL 3rd member, I still have the drum brakes but I have LSD as well. The car came to me like this so I have no other information, but I know it can work!

Hyper4mance2k

iTrader: (40)

The axles are different because the SE axles are 4x114.3 and the 12a's are 4x110. Why is this so hard to understand? other than that they are the same 84-85

13BstreetportFB

because i want the GEARS

13BstreetportFB

i know it will fit the housing... i know that the gsl will give me LSD but NOT a 4.08 gear ratio... the SE bolt pattern is already a given (they are different in that sense) but are ALL GS/GSL/GSL-SE splines the same??? in other words... are the # of teeth on the SE axles the same for GS and GSL?? what about the automatic GSL 3rd member... do they come with 4.08 LSD 3rd members??

steve84GS TII

Yes,.....ALL 84-85 cars have the same size axle splines and outer bearings.The ONLY difference between the 12A and 13B axles from the 84-85 cars,is the lug pattern.The note about a small number of 84-85 cars having the small axles,is news to me.....Ive never come across one in 10+ years.

The SE pumpkin will fit into your 84GS housing with no mods.....end of story.

12akid

4.08 come on auto 1gens ??????? cuz my friend is junking his and it was an auto, ill put it on my 79

13BstreetportFB

thanks guys for the info. I appreciate the help. i'm going to try it. one more question.....does anyone have a gsl-se 3rd member for sale?? haha.. i'm located in LA... i found one for $100 bucks is it worth it??? i heard they might be cheaper???

Siraniko

iTrader: (13)

$100 is reasonable. Its usually in $60 @ junkyard plus your own labor.

Midwest 7's

iTrader: (4)

gsl auto's have 3.90 gears.
$100 is a good deal.

boostedHULK

iTrader: (1)

agreed, 100 bux is a good deal, ****** it up.