Upper Wishbone Arms and Ball Joint

[CliveG]

Would welcome some advice or opinions on this. Whilst checking the car in preparation for fitting polybushes I discovered that my 1960 TR3A is fitted with later TR4 upper wishbone arms and ball joints. I cannot see any marking for LH or RH on the trunnion, so I assume that means the trunnions are the earlier variety with no provision for camber. I have had the car for 3 years and have not noticed any problems with handling (it is not driven hard), so my question is whether this is a problem I should be concerned about or is it an acceptable change to make if the correct parts are unavailable?

The parts fitted to the car are those in the square box on the exploded diagram on this page from the Moss catalogue.

 

http://www.moss-europe.co.uk/shop-by-model/triumph/tr2-4a/steering-suspension/front-suspension/front-suspension-tr2-3a-tr4.html

 

Clive

 

 

[stuart]

Its virtually impossible to fit the later top arms without fitting the 3 degree trunnions so you should be OK

Stuart.

[CliveG]

Thanks Stuart, I am pleased and relieved to know that.

Clive

[Drewmotty]

Count yourself lucky.

If you want to swap for a front suspension which tests your driving ability, stamina and hand/eye coordination every time you drive the car give me a shout.

An upgrade to the later version front suspension is now high on my list of priorities.

Better check that the PO hasn't sneaked a rack and pinion in there too

Andrew W

[CliveG]

So it's a desirable improvement and not a bodge, that's great to hear Andrew. And yes, the PO did put R&P in, but I did notice that :-)

Clive

[Drewmotty]

Even better news; there's a good chance that you'll be able to steer at parking speeds too then :-)

[Drewmotty]

Stuart. When converting do you need the vertical links too or is it just the top wishbones, ball joint and trunnions?

Andrew W

[BlueTR3A-5EKT]

Andrew,

 

If you look at the link to the Moss catalogue you used in the first post you will see that the V.post 201803 is used TR2-4. It is RH threaded and used on both sides of the car. ( I suggest to everyone at this point they get a printed copy of the catalogue for their car from Moss as it contains a whole lot more info than their somewhat clumsy web pages - It is free too. Get it before they decide printing is too expensive)

link << http://www.moss-europe.co.uk/moss-parts-accessories-catalogues.html>>

 

As you have remarked the top wishbones, ball joints and trunions are the only items that changed for the 3 degree castor on the TR4.

 

Read this thread on steering rack v steering box before you go down the rack route.

http://www.tr-register.co.uk/forums/index.php?/topic/54100-steering-rack-or-standard/

 

Cheers

Peter W

Edited November 17, 2015 by BlueTR3A-5EKT

[Drewmotty]

Thanks for your reply Peter; I've now trawled through the parts books and can see that the late TR4 shares vertical links with the 3a.

I had assumed that the late TR4 shared all its parts with the TR4a/5/6 but can now see that is not the case.

So the new questions are:

What is the difference between the TR3/4 vertical Lincs and those fitted to the TR4a/5/6?

Are there any differences in the two 3 degree trunnions apart from the fixed pivot being changed to a separate bolt?

Which parts will be best suited to convert a 0 degree car to 3 degree castor?

Andrew - approaching 40 years in TRs and still learning

Edited November 17, 2015 by Drewmotty

[TriumphV8]

Its virtually impossible to fit the later top arms without fitting the 3 degree trunnions so you should be OK

Stuart.

 

I could see funny things, believe me Stuart that is possible.

The last thing I could watch there was to fit the later wishbones opposite

what in fact means that instead of 2 3/4 positive with the correct trunnions

the axle was pressed to -2 3/4 or a bit less because the axle will refuse to take that position.

 

Anyway if the axle was mounted in the wrong way I would change the trunnions

because they will wear rapidly under those conditions.

Also I would loosen the upper ball joint for testing while the axle is set on post to move freely.

The ball joint should now slip easy between the two wishbones.

 

I swapped a TR3 to modern steering and it was planned to swap to 2 3/4 caster, too.

BASTUCK said that is recommended and the upper wishbones and the trunnions are required.

The owner did not find that necessary after swap so we did not do that.

[BlueTR3A-5EKT]

Thanks for your reply Peter; I've now trawled through the parts books and can see that the late TR4 shares vertical links with the 3a.

I had assumed that the late TR4 shared all its parts with the TR4a/5/6 but can now see that is not the case.

So the new questions are:

What is the difference between the TR3/4 vertical Lincs and those fitted to the TR4a/5/6?

 

The 4A-6 have a larger diameter thread for the trunion and are LH or RH threaded depending on the side they are to be fitted. The 4A - 6 V post has a grease nipple hole in the side of it just above the lock stop abutment.

Are there any differences in the two 3 degree trunnions apart from the fixed pivot being changed to a separate bolt?

 

Yes the thread diameter and the fact the one trunion is LH threaed. The angle they machined at for the wishbone pivot pin defines which side they are fitted on TR4. On TR4A-6 the thread is either LH or RH depending on side to be fitted to. (error proofing I guess on the track)

Which parts will be best suited to convert a 0 degree car to 3 degree castor?

 

Follow the late TR4 design with 3 deg trunions which fit your existing TR2-3 V Posts, Plus top wishbones with ball joints to suit from late TR4/4A/5/250/6 - See the Moss cat

Andrew - approaching 40 years in TRs and still learning

 

 

Cheers

Peter W

[CliveG]

Does anybody know the correct torque for the pair of nyloc nuts and bolts that attach the upper wishbone arms to the ball joint? It doesn't appear to be listed in the manual.

Thanks

Clive