If only R31 skyline diffs were too!! Some original photos have not been recovered yet.

We have 2 diffs apart now and I have been doing some measurements and comparing axle shaft and housing lengths which dismisses the claims that the VN -VS axle is 1 inch longer either side,the bearing retainer on the VN axles sit 2 mm higher than the drum diff due to the thicker seal needed for the rear disc setup. The VN axle housing is 1437MM in length and the VL's is 1400 MM,which calculates to 18.5mm extra overhang either side,before I took measurements I guaged that the axle shafts were both 3/4 inch longer approx in the VN diff and sure enough there is around 18 - 19mm difference in their lengths from the retaining collar. The spline length on the VN is 40mm in length and I want to know whether it is wise to cut these splines down so the shafts fit into the VL diff? I am viewing this as a future option as at this point in time I am just fitting a 2 pinion LSD unit into the VL diff which comes from a Fairlaine. Secondly,do the Falcon/Fairlaine V8's come with a 4 pinion 28 spline centre?,its just something I think is worth looking for in the future.

The 351 Falcon/Fairlanes do have 4 pinion 28 spline. I'm unsure about the 302's though.

Well thanks to all who gave me input on this. I have now performed the heart transplant on my diff, and it drives both rear wheels. The traction difference is amazing, it has to be more than twice as grippy as it was before, now the clutch is the weakest link. 5000rpm launch, and it spun the wheels for about 2 seconds and left 2 5m black marks, then threw back in the seat. Launches hard for an NA I recomend it to any one, the transplant was very painless, but we were also lucky the shims from the LSD diff, fitted perfectally in my housing, and everything meshed beautifully. Some original photos have not been recovered yet.

anyone who has 4.11 diff gears or 3.9 diff gears what revs dose it sit at on 100km/h on the highway?

4.11's - 3500 Rpm

ok guyz i came across this post and recently my 25 spline lsd diff in my vl turbo went bye bye. 2nd diff done in this car lol ive decided to do it properly this time and source a 28 spline diff. i found a vs lsd diff out of a ute but wanted to know if this would bolt str8 up 2 a vl housings and all or if i could use the internals and still use my 3.45 gears and they would all sit nice...any 1 done something like this?

my lsd that a had in the vl before a changed diffs was a 3.45:1, 4 pinion, 25 spline lsd. only bent 1 axle. the 4 pin centre came out of a vn ss, the 25 spline cones came out of a xf, and the axles were standard vl. it coped a fair bit of abuse mainly on the drag strip, and i then opted for a spool, 4.11 28 spline. the gears came out of a pintara.

i just tryed to fit a Falcon LSD centre in my VL the centre fits perfect with same shims and stuff but the crown gear does not match up at all its like 8mm out but everyone says these will fit and all 4 foed LSD centre are the same to small. So we were thinknig bout making up a bit shim for the crown wheel gear but i dont no if thatl work. What do you guys think, how do u no what sort of centre i got. Any help would be great, Thanks Damo!!!

you must have a ford 2.77 ratio carrier. they are completely different to the 2.92 and up. Is like you said they fit in the housing but the 2.77 crown wheel is heaps thicker than say a 2.92-3.23-3.5 You will need a 2.92 or up centre.

Hey, so i have a 2.77 ratio out of a xf fairlane LSD, is it possible to make it fit up to the vl housing, and work perfectly, and i have changed the crownwheel to the 3.45 ratio. Or do i need no matter what the 2.92 or above?? Thanks

im also interested in this aswell? so if anyone could share some information that would be great!

Hey, actually i think i've answered my own question, the reason you can't run the 2.77 is because the hole lsd centre has been moved over, so even if you were to get the crownwheel to line up with the ratio carrier, the axels would be off centre, and the chance of sheering one would be greatly increased because, the axel wouldn't be all the way inside the houseing, so only like stated before, 2.92 or above will work. Who knows with the axel going in further than it should it could result in a very weak spool which would sheer the spline end of the axel off very easily, which is the main reason majority of us are looking for LSD centres not Spools.

so in summary, if you want to 25 spline LSD a stock VL diff, you simply get the LSD centre from a ford, put the 3.45 crown wheel onto the ford LSD centre and put it back into the vl housing and all should be fine?

Yeah but you have to make sure that the crown wheel ratio is not 2.77, but 2.92 and above and yeah then all should be sweet, then just shim it properly and your good to go, but its not goin to take alot of abuse unless you get stronger springs say 200-300 lbs then you can give it hell, (for a while,lol)

Quote: Originally Posted by boostedvl 4.11's - 3500 Rpm What in 4th... Mine sits on 2700rpm with 4.11 in 5th.

i found a XF 2.92 LSD will this LSD deff fit my VL diff. will use tha 2.77 cones and stuff for spares. Thanks damo!!!

HI, ive been told that all ford ratios are the same size so no matter what the LSD centres wont fit with out changing to ford pinon and crown gears. this is what ive just been told, ive searched and searched and all the centres ive found are same size as the 2.77 centre it all bolts in diff but crown gear is way off round 8mm off. so has any1 deff done this lsd conversion if s what centre u deff used. Damo!

YOU CAN'T USE THE 2.77, Who ever told you that is full of it, the 2.92 and above will fit , and does fit perfectly and i have one im my Vl Calais right now and was easy to put in, Cost me $60 dollars and is really tough, Damo, Please read over this hole thread again and what ever question you have, has probably been already answered, Adam Its just abit harder to come by a 2.92 limo, cause the 2.77 lsd's are ten a penny. Buy a 2.92lsd and only a 2.92lsd and you'll have a Lsd!! They might appear exactly the same size but, put them standing up right next to each other and you'll see just how different a 2.77 is to a 2.92, I should no i made that mistake, luckly they let me return the 2.77 and get a 2.92, All went well from there on!! Adam

you cant use the 2.77 ford center.... trust me. i worked with the xd-f falcons for 8 years... 2.92's were usually found on the manuals, lsd in the spac's