Axle/Hubs Weirdness

[Retroanaconda]

Okay, so during my swapping of parts today I have noticed something weird which I cannot explain. I'm hoping maybe someone else will know what's going on here

Some background:

My 110 CSW is a 1993 model. So it came from the factory with drum brakes on the rear. A helpful P.O. has swapped the rear axle for one with disc brakes, reportedly from a vehicle one year later, so 1994. Right in the cross-over period between 200Tdi and 300Tdi, and between drums and discs on the back. So the axle must be an early 300Tdi one then, right?

Well no...maybe?

I have had my suspicions for a while that it might in fact be a drum-braked axle that has been upgraded to discs, due to the fact that it has the earlier (200Tdi and before) drive flanges. These are known as the 'wide type' flange, and look like this:

Later 300Tdi and onwards vehicle have a different hub/stub/driving member setup, which looks like this:

So because my 'disc braked axle' had the earlier wide flanges I surmised that it must be a drum axle converted to discs with spacers between the caliper brackets and the axle tube etc. as per standard conversion people do.

However, it appears to have the later 300Tdi hubs and stub axles. The hubs are thinner, the bearings being spaced closer together, which makes them less desirable in the world of 35" Simex, although for a road car they're fine. Have a look below, earlier (wider hub) Salisbury stub axle on the left, later (thinner hub) type on the right:

I would imagine that because it has the later stub/hub arrangement, this is the reason that there is no spacer between the axle tube and the caliper bracket.

Still, someone could quite easily have put 300Tdi stub axles and hubs onto the (basically identical) 200Tdi axle casing, then added the caliper brackets and bingo. Instant disc brakes.

As it happens there is no trace of the axle number on the casing at all, so I can't actually answer the question as to whether the axle is converted or not. In practice it doesn't matter. The 300Tdi hubs and stub axles will do me fine, the brake discs are the right size, and it all lines up beautifully.

The question I've been trying to answer myself is....

How come with 300Tdi hubs and stub axles, it's using 200Tdi drive members?

I was under the impression that they were not interchangeable. I.E. the PCD of the five M10 bolts which secure it to the hub is different.?

Given that the axle may have come from a vehicle right in the middle of the drums/discs changeover, and Land Rover notoriety for mixing parts, did they ever produce a thin hub, but with the bolt holes for the earlier wide-style flanges?

For what it's worth, the flanges are a reasonably loose fit in the hub. Usually in my experience they are a tight fit, and require to be levered out.

If it helps anyone diagnose, there's also a weird type of thrust washer in place. Much bigger than the standard one and with a different locking method:

And it fitted with the inner bearing nut in place:

So does anybody have any ideas?

It's not a problem, as all my parts fit fine, I'm just curious as to how it's ended up with a hub/driving member combination that I was not aware was possible!

Cheers

[western]

the change point was Chassis LA930435 for 110 & LA930545 for 130's

the driving member bolts for both are M10

wide use FC110107L

narrow use BX110095M additional info here

AFAIK the driving member bolt PCD is the same for both.

the disc braked stub axles

REAR AXLE STUB ASSY

Part number: FTC1740

Applicable Models:

Defender 110",130", LA930456 to 2A638133.

Salisbury type rear axle models.

Product Description:

Salisbury rear axle stub assembly.

For axle codes 38S,39S.

so your 'new' axle maybe one of these ^^^

[Retroanaconda]

AFAIK the driving member bolt PCD is the same for both.

Well if that is the case, then the axle is either:

• A genuine disc-braked 300Tdi Unit with 200Tdi flanges.

or

• A converted 200Tdi axle using 300Tdi stubs and hubs, but retaining the 200Tdi flanges.

[western]

surprised you can't find a axle serial number, can't see why anyone would want to remove it [unless it's a recovered stolen axle]

[Retroanaconda]

I have scrubbed back the rust/dirt with sandpaper but can find no signs. Will do some wire-brushing and see if anything shows up.

Since my hubs are 300Tdi, I might get some thin drive flanges in the future and then I can fit alloys to the rear at least

[western]

if it is a genuine 300tdi axle the serial number digits will be made up from centre pop marks rather than solid line digits like your drum braked axle.

[Aragorn]

I have a theory:

I think its been converted, but the 300tdi disk braked driveshafts are shorter than the drum ones. As such, someones used the odd flanges to get round the fact that its too long. I'm pretty sure the part numbers are different between the disk and drum shafts.

As for the flanges, i was under the impression there was three types, Imperial wide, metric wide, and metric thin?

I've tried the drive flange from my salisbury (which was from a early mid-80's 110) in the 300tdi hub, and its not a snug fit into the bore, it moves around, and the holes dont like up at all.

I've had a look at the shafts, and noticed that the spline end that goes into the diff is quite long, and has a good 10-15mm unused spline (you can see the slight wear marks where its been engaged into the diff splines). The outer end is about 10-15mm shorter. I'm wondering if i turn the shaft round, so the longer splined section is on the outside, then shorten the shaft, or simply cut a replacement circlip groove further in.

[western]

I've tried the drive flange from my salisbury (which was from a early mid-80's 110) in the 300tdi hub, and its not a snug fit into the bore, it moves around, and the holes dont like up at all.

well that pretty conclusive, & clears up what I thought.

As for the flanges, i was under the impression there was three types, Imperial wide, metric wide, and metric thin?

my 110 upto 1986 parts book spec these AFU1181 for the driving member to hub bolts & these are M10 x 50mm with flanged hex heads, never seen that type of 90/110 hubs before.

it also gives the driving members as FRC5806 which are the thick/wide same as on later drum braked axles.

[Aragorn]

So there must be some kinda intermediary flange (perhaps a front flange?) which is wide but has the later bolt pattern and centre bore?

[Retroanaconda]

Well, I'm not sure if it's my flanges which are different or if it's my hubs

Got the other sides done today, same setup. All back together now with new brakes etc. so hopefully that should be the rear axle sorted for a while at least!

[Aragorn]

Well fwiw i stuck a vernier caliper over the two drive flanges today. The drum braked one had a spigot diameter of ~77mm and the 300tdi one had a diameter of just under 80mm.

The bolt PCD is slightly smaller on the drum drive member too, so the drum drive member really wont fit the 300tdi hub.

But it seems you have a pair of 300tdi hubs attached to early drive members...

I'll have to have a bit of a look over the part numbers and see if a drive member exists thats thick but has an 80mm spigot, just for completeness!

[Retroanaconda]

When you say the bolt PCD is slightly smaller, is it possible that someone has drilled out the holes in the flanges slightly, to allow use with the 300Tdi hubs?

The flanges are definitely loose in the hubs, in practice it doesn't matter as the bolts hold them firm, but it's clearly not a match that's meant to be. When I'm next doing something with the rear hubs (won't be long, knowing this thing...) I'll try a 300Tdi drive member in the hub and see what happens

[Aragorn]

Ye i guess its possible someone could have drilled them out?

The stock holes are a very snug fit round the shank on the bolt, so it should be pretty obvious if its been fiddled with.

I'll let you know how i get on if i get it bolted together with 300tdi flanges before you try it!

[western]

I can only find 2 parts numbers for 90/110 hub driving members in all my parts info

FTC859 now superseded buy RUC105200 [300tdi on]

FRC5806 everything inc 200tdi vehicles