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View Full Version : Converting 1954 CVs to earlier Tracta Joints - Whats involved?



Yorkshire_Jon
31st December 2014, 11:39 AM
Hi all,
I recently started to partially strip my front axle to install 11" x 3" brakes from a 6 cyl.

Whilst I was elbow deep in grease I thought Id go the whole hog and replace all bearings and seals...

Now I have the half-shafts out Id like to replace them with earlier tracta-joint variants so that I can use the permanent 4WD from my R380/LT230 combo.

I know its possible to swap CVs for tracta's but I don't know what else is involved. Is it a straight swap or do I need different seals, bearings etc etc?

Anyone know where I could drop on a pair of good tracta-jointed half-shafts?

Thx
Jon

wrinklearthur
1st January 2015, 08:02 AM
A couple of things;

The inside half shaft for the 80" Tracta joint is located by a ball bearing and this is in turn fastened by sleave that is shrunk onto the half shaft and to service this, a workshop press of twenty tonnes is required to dismantle the shaft from the swivel pin ball housing.
To take the diff out of the front of a 80", the flanges at the inside of the swivel pin housing's to the diff housing has to be separated, to be able to withdraw the axle half shaft's from out of the diff centre.

The 1954 to late Series 3 had Universal Joints in their front axles, not Constant Velocity Joints ( CV's ), but I know what you are getting at, that is that kick in the steering experienced when powering on full lock.

I don't know of any modification that allows a Discovery or similar, CV to be fitted into the early swivel pin ball housings and I would like to know if this has been done?
The Stage one had CV's, but the diff housing is longer than a Series 1 , so the whole front axle assembly would need to be changed over.
.

isuzurover
1st January 2015, 08:14 AM
...

I don't know of any modification that allows a Discovery or similar, CV to be fitted into the early swivel pin ball housings and I would like to know if this has been done?
The Stage one had CV's, but the diff housing is longer than a Series 1 , so the whole front axle assembly would need to be changed over.
.

Maxi drive used to machine the inside of series chrome balls to allow 110 AEU2522 cvs to be fitted.

Worth noting that there are plenty of 4x4s which were constant 4x4 with ujs.

Yorkshire_Jon
2nd January 2015, 09:12 PM
A couple of things;

The inside half shaft for the 80" Tracta joint is located by a ball bearing and this is in turn fastened by sleave that is shrunk onto the half shaft and to service this, a workshop press of twenty tonnes is required to dismantle the shaft from the swivel pin ball housing.
To take the diff out of the front of a 80", the flanges at the inside of the swivel pin housing's to the diff housing has to be separated, to be able to withdraw the axle half shaft's from out of the diff centre.

The 1954 to late Series 3 had Universal Joints in their front axles, not Constant Velocity Joints ( CV's ), but I know what you are getting at, that is that kick in the steering experienced when powering on full lock.

I don't know of any modification that allows a Discovery or similar, CV to be fitted into the early swivel pin ball housings and I would like to know if this has been done?
The Stage one had CV's, but the diff housing is longer than a Series 1 , so the whole front axle assembly would need to be changed over.
.

Thanks Arthur.
Apologies for using the word CV, I did of course mean UJ. So I guess my question is how easy is it / is it possible to replace my 1954 86" UJ half-shafts with tracta-joint half shafts out of an 80 whilst retaining my diff.

Thx
J

Timj
2nd January 2015, 10:03 PM
The tracta joints had the different bearing on the diff side and they also had a brass bush inside the stub axle. I believe this was because they needed to be kept in place more solidly than a universal. While they are a fascinating joint it would be difficult to find one in really perfect condition as it is now sixty years since they were used. However to answer your question there is no good reason why they could not be swapped in as long as you use the right bearing. The later swivel housing actually has more room so won't be a problem.

Cheers,

TimJ

JDNSW
3rd January 2015, 06:08 AM
The tracta joints had the different bearing on the diff side and they also had a brass bush inside the stub axle. I believe this was because they needed to be kept in place more solidly than a universal. While they are a fascinating joint it would be difficult to find one in really perfect condition as it is now sixty years since they were used. However to answer your question there is no good reason why they could not be swapped in as long as you use the right bearing. The later swivel housing actually has more room so won't be a problem.

Cheers,

TimJ

Correct - the universal joint, and the later Rzeppa joint are self aligning, whereas the Tracta joint (actually, when you analyse it, really a double Cardan joint) requires external alignment.

While both types of joint date from about the same time (Tracta 1926, Rzeppa 1927), the Tracta joint remained the CV of choice until the late 1950s. The reason for this is that the Tracta joint is easy to manufacture, being tolerant of inaccuracies or wear, and because of the large bearing area, not very demanding of materials, whereas the Rzeppa joint is very difficult to manufacture as it needs to be very accurately made, and heat treatment, materials and lubrication are critical.

This suggests that manufacturing new Tracta joints should not be beyond the capabilities of any modest engineering workshop that seriously wants to do it.

isuzurover
3rd January 2015, 08:47 AM
...

This suggests that manufacturing new Tracta joints should not be beyond the capabilities of any modest engineering workshop that seriously wants to do it.

However it would probably be cheaper and easier to get the balls and stub axles machined to take aeu2522 or rrc cvs. You would also have off the shelf replacements.

Barry at hitough probably still does this, and can supply the right inner halfshafts.

Yorkshire_Jon
13th January 2015, 03:05 PM
I spoke to Barry at Hi-Tough and he advised he can't do the machining and further suggested that Id be OK to keep the UJs.

He said (similar to my initial thinking) that because the LT230 has a centre differential then there would be no transmission wind up and so the UJs would be fine, i.e. no need to replace with Tracta's or the later CVs.

Also, not sure if it complicates things or makes things better for me - my front axle has free wheeling hubs fitted. This means that I either need to engage them all the time to get movement, or keep them dis-engaged and engage the centre diff to allow forward movement.

For now I'm going to leave the UJs in place and see how I get on.

Thoughts please.

Thx
Jon

isuzurover
13th January 2015, 04:00 PM
I spoke to Barry at Hi-Tough and he advised he can't do the machining and further suggested that Id be OK to keep the UJs.

He said (similar to my initial thinking) that because the LT230 has a centre differential then there would be no transmission wind up and so the UJs would be fine, i.e. no need to replace with Tracta's or the later CVs.

Also, not sure if it complicates things or makes things better for me - my front axle has free wheeling hubs fitted. This means that I either need to engage them all the time to get movement, or keep them dis-engaged and engage the centre diff to allow forward movement.

For now I'm going to leave the UJs in place and see how I get on.

Thoughts please.

Thx
Jon

Most LR people don't think you can have constant 4x4 with UJs, however Jeep (and others) did it for many years. You may get some slight feedback in the steering wheel on tight corners, but that is all.

Lotz-A-Landies
13th January 2015, 04:09 PM
You could always fit a stage 1 front axle and SII/SIII 88" rear axle, which will also give you a little better turning circle) . Or you could talk to Barry about making up some short S1 length halfshafts for the Stage 1 swivels, these will bolt up to your S1 housing.

If you need some 80" front axle components, I took a heap of them out to storage at Maralya I'm sure we can come up with enough bits.

Yorkshire_Jon
13th January 2015, 04:20 PM
You could always fit a stage 1 front axle and SII/SIII 88" rear axle, which will also give you a little better turning circle) . Or you could talk to Barry about making up some short S1 length halfshafts for the Stage 1 swivels, these will bolt up to your S1 housing.

If you need some 80" front axle components, I took a heap of them out to storage at Maralya I'm sure we can come up with enough bits.

Thanks Diana,
Different axles and bespoke bits all sound a bit more involved (read expensive) than Id like just at the moment... Perhaps I may think again when I get it back on the road, have lived with it "as-is" for a while and have decided that I need to swap the diff out for a 3.5:1.

Re the bits from storage - many thanks for the offer. I'll bear it in mind - I'd rather contribute to friends hobby funds rather than commercial entities.

Lotz-A-Landies
13th January 2015, 04:26 PM
A Stage 1 front end will bolt straight up to an 86" and only widens the track by the thickness of the drive flange on each side. You do however have to swap the bottom steering lever to one of the cranked levers off any of SIIA or SIII vehicles.

With the rear axle, any 88" SII/SIIA/SIII rear is a straight swap, no modifications.

wrinklearthur
14th January 2015, 10:09 AM
A Stage 1 front end will bolt straight up to an 86" and only widens the track by the thickness of the drive flange on each side. You do however have to swap the bottom steering lever to one of the cranked levers off any of SIIA or SIII vehicles.

With the rear axle, any 88" SII/SIIA/SIII rear is a straight swap, no modifications.

The half shafts ( scarce to find ) in a Series one are 3/4" shorter than the Series 2, 2A, 3 and Stage one.

The spring centre bolt position in the axle housing is the same as the front in a 1950 onward ( wide spring leaves ) and the rear and front spring from 1954 onward.

So it's possible to do as Diana said and fit front axle from a series 2 onward into a Series one, with the benefit of the wider track allowing a tighter turning circle before the wheel rubs against the spring.

Also the wider track of a Series 2 onward when installed into the rear of a Series one and while using larger tyres ( 7.50 x 16 ), allows better vertical axle articulation before the tyres run on the insides of the mudguards.
.