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Discussion Starter · #1 ·
Believe it or not the sun shone today in the UK.

So I took the chance and took the old donkey out for a drive.

She drives absolutely beautifully BUT...............I detect a kind of wobble/shimmy through the car. I don't think it can be wheels as I had those balanced. It comes in around 55 and feels more obvious at 60 plus.

Dont seem to be able to drive through it which makes me think prop???

Anything obvious that I should know about on these cars??
 

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Yes, from the sound of it you have worn Detroit (AKA Ball & Trunnion) joints (a common problem in the SY cars).

Very often the trunnion joints have had long neglect in their lubrication. When they leak (and they all do) it slowly drains into the differential so you have no idea they've gone low/empty. Over time the faces wear unevenly and you get a shudder/shimmy once you reach 55 to 60 MPH that sometimes, but not always, goes away at higher speeds.

The good thing is that if they've never been changed from side to side you can do that and get two new wear surfaces that could last several decades. If this has been done before then your best bet is to find a set of Lobro joints that were used on the Spirit/Spur series cars and fit those instead of the ball & trunnion/Detroit joints.

Good luck.
 

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Discussion Starter · #3 ·
Great stuff...Thanks for the reply. I was beginning to think everyone had done a runner on this forum :lol:

Is it generally an expensive job/time consuming?

Thanks
 

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I'm interested in this fix as well, since my car has the vibes at around 60 and they gomaway by 70. I have not looked into it as I am moving, but would love to fix this problem and make the car fell less like a pinto.

Thanks
 

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Try filling the trunnions up (I think they get 150ml each). I greased the outside U-joints at the rear wheels at the same time, so that might also have been an issue. In any case, it smoothed it right out for me.

Jeff.
 

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Discussion Starter · #6 ·
There you go again Jeff...getting all technical on me.

I need to go find a picture :lol:
 

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Not that it might not help sometimes, but don't think that adding lube to the trunnion joints will necessarily be a quick fix. These should be checked annually (ideally) as you'll virtually always find that there is slow leakage into the differential. This can be a particular surprise if you open the differential fill hole when everything's hot and have a gusher come out.

See Workshop Manual Chapter J, Section J2, for details on the trunnion joints.

Also see PDF pages 11 & 13 of Tee-One Topics, Issue 44 for additional details on these "mystical" bits.
 

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Discussion Starter · #8 ·
My problem is that I haven't got the time to get my head around all the technical stuff or the time to do the job. I'm currently restoring my S1 E Type and that is more than enough for my little brain :?

So if I took this to my local RR expert is it considered one of those sucking through the teeth expensive jobs?
 

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Viper,

First, be aware that I am not intending to throw snotty attitude at you in this response.

If your local RR expert is like most RR experts then the amount they charge hourly for labor will push all but the simplest jobs into the "way too much money for my wallet" area. Many jobs don't require RR experts, either, but some do. This one would not if the mechanic is skilled and willing to look at the workshop manual to determine whether he/she is up to it or not.

If you are planning on taking this to someone else familiar with cars from Crewe I'd really suggest you acquire the later Lobro joints that were used on the SY series cars and fit them in place of the existing ball & trunnion (AKA Detroit) joints. It's a far more trouble-free solution, you'll not have to worry about ever doing the job again, and they're less high-maintenance.
 

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wibbly wobbly

The other problem to consider is that vibrations can be very difficult time/ consuming to eliminate, as it is quite often a trial and error situatuion to actually pin point it down to 1 component. Are you certain that the wheels have been balanced accurately , that the balancing equipment was calibrated the slightest buckle on the wheel can make an enormous difference on these cars. I have even had to balance wheels with trims on to get them accurate and have used an adapter that bolted the wheel on its studs to get accurate balance. May be worth getting them balanced on the car if you can find somewhere with an on car balancer.Tyres would need checking for any runout/ flat spots to eliminate them if the car stands alot then the tyres will have flat spots. Is the standing height at the back of the car low, this can cause vibrations as the driveshafts are inclined upwards towards the wheels Hope this is some help, owning and maintaining a shadow is never easy nor quick but can be fun
 

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Very good info. I intend to change the oil in the shafts first, then raise my rear back up since I converted the brake hydraulics to simple new age design of hydroboost and standard master cylinder. I am converting the rear rams to remote reservoirs with height adjustment in the trunk for the seldom times I might need to raise the rear even more. It sounds like most of the vibes are related to having the axle shafts in perfect working order and positioning. And you guys are right, most jobs on these cars can be performed by anyone with all the right tools, some ability, and willingness to understand how the systems function before disassembly or the latter, giving up....
 

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Discussion Starter · #12 ·
All very good sound advice and I'm grateful

I trust my wheel balancer and I have thought about the possibility of flat spots on the tyres.

Maybe coincidence but this driveshaft/trunion wobble is characteristic at the said 60mph.

I have guys at hand that could do the job and I pay their wages day in and day out but their time has to be billed and it often cost me more through a lack of familiarity.

I guess I ought to start looking at buying a manual or is it downloadable?
 

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One other word of warning: the trunnions *usually* leak into the diff. My O/S one, for whatever reason, leaks out the boot opposite the diff. (I can tell because my fuel pump is always covered in gear oil.)

Jeff.
 

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Do this wobble gradually appear? If so the advice about driveshafts is good.
If the wobble came about within a few miles or whilst car was stored, then it is not lighly to be drive shafts. Here are a few possibilities...
Stupid question, but are the wheel nuts tight?
Consider the possibility that engine or gearbox mounts have broken.
If you have a stainless exhaust, it could be that system resonating, not a wobble at all (don't laugh, I have had that issue).
 

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Whatever happens give the 1/2 shafts a grease. . . . until ALL 4 of the spiders are emitting clean grease. If you see Rust red grease coming out it usually is that - rust and the needles will be beyond repair. White light coloured is usually water ingress, but you may have caught it in time. None out of any of the spiders, take it for a run and try again. If it is in the hub side you are lucky and can easily remove the yokes. Poke any solidified grease out and try again. (pack the needles with grease on assembly)

Drain the diff when hot and fill with new oil. Fill the 1/2 shafts. Turn the shaft so the drain plug is higher to fill them, then turn them horizontal to find the correct oil level.

You would be shocked by the amount of full service history cars are completely empty and dry.

These 1/2 shafts are incredibly over engineered ~ but MUST be well lubricated!
 

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Discussion Starter · #17 ·
Thanks Paul

Spoke to my local Specialist today who says that if the trunions are shot or the UJ are kippered then is would only generally show when under hard acceleration.

I noticed today that there is a vibration when leaning into corners. Everything is pointing towards the opinions on here including yours....stands to reason really.
 

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Hi Viper,

I'm not 100% convinced that your 1/2 shafts are the problem but am convinced that they (all) need greasing and filling regularly. It's quick, simple, and cheap. I don't know why so many garages/people do not bother with them. Well ~ apart from the danger of getting covered in oil that smells like Tom cats **** :)

The trunnions usually give vibrations under acceleration if dry and worn, but the outer UJ's can give odd wobbles at low speed gentle starts as well.

At 60mph it could well be a wheel or tyre problem. Especially if the car has been sitting still for a while.

I would try swapping front and rear wheels and see if the wobble moves to the steering wheel. Always a good test for wheels.
 

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Discussion Starter · #19 ·
Yes...tyres could well be the issue as someone had already mentioned.

I do remember seeing sticky oil running over the rear exhaust when I originally went to view the car so this could well be the issue.

Is there a service instruction manual/procedure on this somewhere?
 

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