Mismatched Tie Rod Ends and Accidents

**JDNSW** · 28th March 2012, 05:55 AM

Originally Posted by 123rover50

Its not mismatched threads that seem to be the problem.
The pitch and all match, it appears to be the clamping force of the clamps.
I feel the clamps are there only to stop rotation and the longitudinal clamping force of the clamps would be minimal. This is the function of the threads. So far failures appear to be from rust and corrosion not from the rod unscrewing or stripping sound threads.

The threads as you say, are the same. The failures result from the clamping being ineffective because the area of contact is inadequate. This can result in either the joint unscrewing or wear on the thread due to movement weakening the thread and consequent failure.

The problem is simply that you cannot rely on clamping being effective where you are clamping a thread against a flat surface. OK, you will get away with it a lot of the time, maybe most of the time - but do you really want to rely on "most of the time" when talking about steering?

John

**JDNSW** · 28th March 2012, 05:59 AM

Originally Posted by Lotz-A-Landies

The tread in the completely threaded and shouldered series TRE are the same, but how much wear will there be in the threads of a 50+ year old vehicle?

I guess the issue becomes, when should you replace tie rods and not just the TRE!

If the clamp has always been secure (and hence no movement on the thread), there should be no significant wear, even after fifty years. Rust is a more likely problem (or bending due to impact!).

Replacing the tube should be on condition.

John

**chazza** · 28th March 2012, 07:58 AM

There was case reported in LRO International some years ago, of a father and son dying in their S1 when they lost all steering and crashed through a stone wall. The investigators put it down to the wrong TRE somewhere in the system.

Remember also that the rods have slots cut in them, so when the clamp is done up the end not only grips on the shoulder but it causes the female thread to grip on the male part.

I used Loctite anti-seize on mine to stop rust; galling and fretting and I guess regular inspections are a must,

Cheers Charlie

**Psimpson7** · 28th March 2012, 08:13 AM

Originally Posted by chazza

There was case reported in LRO International some years ago, of a father and son dying in their S1 when they lost all steering and crashed through a stone wall. The investigators put it down to the wrong TRE somewhere in the system.

I recall that story, but thought the cause was the fact that the track rod had rusted through as opposed to a TRE issue...

**123rover50** · 28th March 2012, 05:42 PM

I dont have a problem with using the shouldered TRE,s. I bought them off Alex at the Series one shop for the rebuild of Borumbah and Tristan but I have yet to hear any hard evidence of mismatched ends causing these fatalities .It appears to remain an urban myth.
Perhaps a comparison using a strain gauge and testing to destruction would give a result.
I posed the same question on the UK forum with no replies. At least here there is some discussion even if no definitive answer.

Keith

**B.S.F.** · 28th March 2012, 10:31 PM

Last year?... after driving the car daily for about ten years including several outback trips on very rough roads,I started to get kickback at the steering wheel. Upon inspection I found that the longitudinal steering tube was too short and clamped one TRE on the thread. That was the only TRE that had worked loose.All the TREs were of the shouldered type.In all fairness it must be said that because of the short tube only about 3/4-1" of the thread was engaged.
W.

Thread: Mismatched Tie Rod Ends and Accidents

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