Changing diff ratio's. - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

xf351clev · 07-07-2004, 22:30

When changing diff ratio in a XF do u have to replace the housing or can the new centre go into the old housing , Also if the housings don't have to be changed will the centre out of an E series fit an XF housing.

gtcoupe95 · 07-08-2004, 17:15

just ring gear and pinion needs top be changed. and you can install xe to eb1 25 spline centres..
just to be sure xe351 used a 28 spline diff.. i know all xf's are 6cyl and 25spl but i would check to make sure it hasnt been changed b4

xf351clev · 07-08-2004, 18:05

sorry for my ignorance gtcoupe95 but what do you mean by top be changed? The diff in mine was from a xf fairmont with 2.77 and be wanting to throw a 3.08 or 3.23 into it would prefer 3.08 or would it just be easier to put in a e series diff and housing.

MrLandau · 07-09-2004, 02:49

Because of the offset of the 2.77 XF LSD - you cannot change ratio's... Some carbied XF's came with 2.92 o/w which will take the "Normal" LSD centre which will accept any of the BW 78 ratios from 2.92 to 4.11. You could always use a 2.92 LSD from a ZK and change gears on that.
Shane
(Falcon City - Adelaide)

xf351clev · 07-09-2004, 19:19

do lsd diff's use bigger bearings or was it the offset as i try'd to put a 3.23 into the housing a week ago and when i torque'd it up the centre would not turn so put the 2.77 back in and was ok. Thought it was something i was doin wrong or that u couldn't change ratio's without changing the housing hence this thread

MrLandau · 07-10-2004, 00:39

Quote:

Originally Posted by xf351clev

do lsd diff's use bigger bearings or was it the offset as i try'd to put a 3.23 into the housing a week ago and when i torque'd it up the centre would not turn so put the 2.77 back in and was ok. Thought it was something i was doin wrong or that u couldn't change ratio's without changing the housing hence this thread

No - it is the physical size and offset of the 2.77 LSD which makes it different to everything else and therefore useless to most of us...To change ratio's you will need to go back to a ZK/FD 2.92 LSD housing and centre.
Shane
(Falcon City - Adelaide)

xf351clev · 07-11-2004, 06:04

do all ZK's have lsd or are some ss as priced one from a local wreckers for $150 minus brakes but will use mine anyway as there slotted.

MrLandau · 07-12-2004, 02:17

Back in the good old days - all Ford V8's came with LSD's. If the ZK was a V8 one it will have an LSD tag on the cover plate. Make them prove to you it is an LSD centre before you purchase it.
Regards,
Shane
(Falcon City - Adelaide)