diff questions

stockstandard · 27-08-2005, 03:02 AM

What e-series housing take what gears?

I know this has been asked before, but after some searching on various forums it seems like there is a different outcome each time it is asked. I have always believed that if you had a 3.XX housing you could swap for any other 3.XX gear but now i have read:

Quote:

You cant fit 3.45 LSD in 3.08 SS housing because the 3.08 is a 75 series diff, 7.5" crown wheel, and 3.23/3.45 are 78 series with a 7.75" crown wheel. ... Even if you change carrier it wont fit

yet another thread states

Quote:

all the falcon diffs from early X series are 78 series

then I read...

Quote:

The 3.23 diff housing is differnt where the pinion goes in so the pinion from a 3.45 or 3.08 gear set will not fit. If you put the pinion from a 3.45 or 3.08 next to a 3.23 you will see the difference where the collapsable spacer fits over the pinion

then find...

Quote:

You need min a 3.23 housing to take the 3.45 gearset

finally...

Quote:

I have done this swap with a ed diff. I used the 3.45 ring& pinion into a 3.08 ed housing.

Quote:

(regarding ED xr6 center into EF GLi housing) it will bolt straight in

Quote:

all EBII onwards to EL axles are the same, the only difference is between ABS and non ABS. the centers (all 4 pinion) and diff gears between those models are all the same, and are also the same as VL onwards live axle commonwhores and australian R31 skylines and pintaras, though pintaras only have a 2 pinion center..

Can anyone verify that last statement regarding all centers from eb2 onwards are 4 pin?

Anyway, now Im very confused. Im have a 3.45 LSD center on the way, have 3.08 ss in the ef at the moment, and have a spare 3.23 ss diff as well. I want to turn one of these diffs into a 3.45 LSD and would prefer not to have to pull them all down to see what fits.

Does anyone KNOW FOR SURE what the deal is with these housings? Can any 3.XX diff housing be fitted with 3.45/3.7/3.9 gears?

(sorry for the long'ish post)

toby123 · 27-08-2005, 03:57 AM

MY EF Fairmont i6 started as a 3.08 SS but i had 3.73's put in, so I definatly know they fit in them....

AUII_Forte · 27-08-2005, 11:37 AM

I went to put 3.45's into my AU's 3.08 housing and there was no way in hell they were fitting. Something about the pinion height.

EFFalcon · 27-08-2005, 01:22 PM

Rmyers had 3.7's fitted to his diff, the diff was a 3.08SS from my EF GLi.
he also had the option of 3.9's, but the 3.7's came out of a HSV.

Aaron_EF8 · 27-08-2005, 01:33 PM

Quote:

Originally Posted by toby123

MY EF Fairmont i6 started as a 3.08 SS but i had 3.73's put in, so I definatly know they fit in them....

Are you 100% sure it was a 3.08 SS diff? ALL EF Fairmonts got a 3.23 diff as standard. The only way it could have got a 3.08 is if it was swapped during its life.

toby123 · 27-08-2005, 02:04 PM

Quote:

Originally Posted by Aaron_EF8

Are you 100% sure it was a 3.08 SS diff? ALL EF Fairmonts got a 3.23 diff as standard. The only way it could have got a 3.08 is if it was swapped during its life.

Ok Then..... I didnt realise that... OK so it didn't start as a 3.08 :P

EDIT: but at 100k/hr it was doin about 1800rpm in 4th, i thought that was about right for 3.08?

stockstandard · 27-08-2005, 04:57 PM

According to the Max Ellery's EA-ED repair manual, these falcons did come out with both 75 and 78 series assemblies. The 75 series has a 190.5mm ring gear and the 78 is 196.8mm. It does not say which series came out with each model/ratio, or if the centers are interchangable.

My Haynes EF/EL repair manual is useless when it comes to diffs. Anyone have a better one?