r200 diff install into 240z. Halfshafts don't fit? Help please

[Retro Z]

Hi guys need help again.

 

Just finished fitting a r200 from a 75 2+2 into my 240z.

 

The diff, mustache bar, control arm mounts etc all fit up fine, but the halfshafts dont fit up to my 240z hubs.

 

My hubs are from a 72 240z possibly jdm fairlady z. Halfshafts are the r200 ones and were alreeady attached. In fact i removed the entire assembly from the car so i know its all correct

 

The holes dont line up at all and are about 5mm off. Tried rotatkng etc but no luck. From all the articles and FAQ's i read about this install they say to use the halfshafts that belong to the diff in this case i have.  Also several claims say not to use the r180 halfshafts as the r200 as different length shafts due to the offset of the diff. I no longer have the original shafts.

 

Does anybody have any solutions? Anyone have this problem? What shafts can i use?

Any help would be appreciated.

 

Thanks Tai.

[Ledge]

Hi

Think you need to use the companion flange of the car the R200 came from as well and because

they would have more splines you would need to use the Stub axle as well.

I'm not 100% sure though

 

Cheers

Paul

[dat2kman]

You do have the stubs that go into the diff, that belong with the R200, yes?

Yes, then good!

No, not good,  get them, they are unequal length, a right and a left.

 

The half shafts you got with the r200, how do they compare to your originals, if flanged at each end?

Compressed length, extended length?

 

The bolt pattern on all car variants are the same, the bolt pattern is in a rectangle, not a square pattern.

Some trucks with front diff have different shafts to the car variants.

 

When i swap over diffs in my S30, r200, i have to not do up the front diff mount, so I can push the diff nose over a bit, just enough to get the left hand half shaft to fit between the flanges on stub and outboard hub, then i straihgten the nose and bolt it all tight.

 

1600 sedan, 240k, irs 200B 260 and 260 2+2 half shafts are all the same, save for uni joint grease fittings.

 

[gilltech]

Your info is correct - keep the respective half shafts with their diff as a set.

I've done the reverse with no problems, fitting a complete R180 incl halfshafts into my manual 260 as a temporary replacement to keep me mobile until a sound replacement R200 was found. All bolted up, didn't have to change anything on the wheel hubs.

Are you quite sure you have correctly tried rotating one of the mating flanges 90 degrees? It's been a fair while but I recall the hole pattern being offset, ie. slightly rectangular not square. Fit everything up loosely first, the halfshafts need to be wriggled around & rotated as required to correctly slot into place especially at the wheel flange end.

Now I'll have to look at my spare R200 under the house in daylight tomorrow to check if my memory serves me well.

 

[Retro Z]

Thanks for the help guys.

 

The half shafts definatly dont fit on the wheel side.

 

They are 4 bolt flange just like my old r180. I left the shafts on upon removal from the 2+2 and just undone the 4 bolts on the wheel side and tried installing in the 240z in the reverse procedure. Ive done diff installs and removals several times but this is the first time doing a conversion. Should all just bolt up...

 

These half shafts flanges are rectangle and the flange on the hub/wheel side is square. I actually measured the holes and rotated and it definately does not fit.

 

Weird...even my workshop manuals say its correct.

 

Are jdm fairlady hubs different, as im quite sure my 72 donor car was one as it had the l20 engine.

[gilltech]

Just checked my 260 with R200, & my spare R200, & all bolt patterns are rectangular, roughly 50mm one way & 55mm the other. And the R180 I used years ago must have been the same or it wouldn't have fitted.

Can't imagine why 200Z wheel flanges would be different to 240/260Z models, but they must be.

Ledge's posting above is right, either find a pair of 'square' flanges to install on the R200 halfshafts - can you get yours back? or perhaps someone on this forum has got a pair - or, change the wheel hub but who knows what that would entail until you pull it all apart & compare.

However, just a thought - for the engineering gurus on this forum - can the 'rectangular' half shaft wheel end flange be re-drilled to fit the 'square' 200Z hub? Ie. changed to a square pattern, shifting all holes sideways by approx 2-3mm, inwards or outwards you measure your wheel hub flanges & advise.

 

[Scoota G]

Perhaps the R200 is from something else!

[Whittie]

Scoota sounds like he's on the money

 

I've got a silvia R200 in my car and it has different flanges.

 

If you can get the drive shafts from the 2+2, perhaps that would work? I'm not sure on drive shaft lengths, but maybe....

 

Otherwise, you may need to do what I did: Cut the flange off the shaft and weld on the flange from your previous diff. Not a lot of fun for the shop that does the work, but been working great for me, twice.

[Riceburner]

JDM Fairlady is the same rectangular bolt pattern as standard r180/r200 and the half shaft will fit in any combo. Sounds like a diff from different model.

[Retro Z]

The diff was removed by myself from Vivek's (Vramjee's) gold 75-76 260z 2+2 so i know its correct as it was working on his car.

 

I got access to another set of r180 halfshafts that i will try..some people say they will fit others say they wont as r200 is supposedly offset, but i will measure and soon find out. I'll be sure to update on my findings.

 

Cheers guy appreciate all the help and effort, thats why i love this forun

 

Tai

[Scoota G]

Why not go get the rear hubs and flanges off Vivek too!

[Retro Z]

Yeah i might have to Scoota..but kinda dreading the spindle pin removal, mine was a nightmare to remove. Im getting some r180 shafts dropped off today so see how that goes first.

[gilltech]

Have I got this the right way round, your wheel hubs have the correct usual Z rectangular bolt pattern, whereas the (possibly unknown model) R200's shafts have the square pattern?

Query for the experts: can the R180 end flanges be fitted to the R200 half shafts at the universal joint, or are they different sizes? (Sorry, I don't have an R180 here to compare myself).

Or, as an alternative to cutting & welding as Whittie has done, I ask again whether the offending holes can be welded up & re-drilled to suit your wheel hub pattern? Do the flanges fit & mate up correctly other than the actual bolt pattern?

[Retro Z]

Problem solved guys. Got a pair of halfshafts off another r200 from a guy wrecking his 260z nearby. Bolted up perfectly. Also tried the r180 shafts but one side was half and inch too short.

 

Still unsure, but it seems the diff i got is from something else. I know it was from a 75 260z but could have possibly been retrofitted. I found a thread last night on HybridZ and there was talk about the 75 260z having different tailshaft flanges aswell as halfshafts only for that year....

 

I also just swapped pedal boxes as i upgraded to a 260z booster and once again it doesnt fit. Distance between booster hole and clutch master holes are different compared to the holes on the firewall, seems there are 3 types....really getting over this Z  :-\

 

 

Anyway Thank you to all that helped. Much appreciated.

 

Tai

[gilltech]

Glad that's sorted, very frustrating for you. Educational for us all though, this forum is great for sharing knowledge.

Yes the 240 & 260 look so much the same but many parts just don't interchange across the years as you'd think they would. 260 owners have to be careful too, early vs mid vs late production.

There's been quite recent discussion on this forum about pedal box swaps 260 into 240, might pay to check it out.