Outer Limits 4x4 Board

hey guys just wanted to no if 87 3.9 gears will fit on 89 3.6 centres

Just swap the complete centre in , You will find the flange is bigger on the 89 by about mmmmm 15mm in bolt hole patern diameter. But check it first You may be lucky ,so you will need to use a rattle gun and remove the flange and replace with the larger daimeter one and whil you have this off replace the seal
If im correct there only about $10 , the seal runs on the flange .
If you have a locker in the 3.7 just put it in the 3.9 hemi

Oh forgot to say there refered to as 3.7 by most zook people


Larry.

if this is tru it wont work as i run air lockers front and rear.

bazooked wrote:if this is tru it wont work as i run air lockers front and rear.

air lockers are the same for 3.7's as 3.9's I think, so you can change ya diff gears and still keep the locker, but I don't think the pinions are the same, so you need to match the correct pinion with the crown, but all the rest is ok, and yes the flanges are often different bolt patterns, christover

Crown and pinions are matched and shouldn't be interchanged.

bazooked wrote:if this is tru it wont work as i run air lockers front and rear.

I just gave you the moct cost effective way to slip in your gears ,

in your case with air lockers , you will have get a crush sleave and go through the hole gear setup antics , our you could just drill the 3.9 housing to take the air line and swap thr hemispheres , is up to you ,

3.9 ring and pinion , and 3.7 ring and pinion will bolt up in the same centre, as cj stated the ring and pinion are matched and machined to suit each other don,t try to mix them.

Larry

when u said the flange was bigger i assumed the crown wheel flange, not the tailshaft flange , my mistake, any how i wouldnt mix and match gears as ive built a few diffs over the years,

graeme.