TRCM

Really ??

that can be said of almost ALL bolted connections.............

guess we're all gonna die...better take off the aluminum rims and put on steel, or find ya some aluminum lug studs/nuts..........

Don't forget them aluminum connecting rods held together with steel bolts....

TRCM

That is all kinds of wrong....SAFETY should always be the main priority.....unless you want to get dead....or kill someone else !!!

LACK

Tie rod ends into a cast knuckle vs Tie rod ends into whatever type of steel X manufacturer wants to make the inserts out of. I've personally seen inserts fail on more than one occasion.

So, YES really. Do some research before making a condescending comment.

Have fun

http://papers.sae.org/2004-01-0628/

TRCM

whatever dude.....wasn't meant as condescending, but I guess you took it that way. Do you always assume people are talking down to you ??

It was meant more as "explain why these other dissimilar metal connections work' than anything else.

That link has nothing to do with the problem you are claiming. It is talking about fatigue analysis of the knuckle itself, and the materials the knuckle is made of....way way different from the stresses the insert sees. It is talking about a cast steel vs aluminum vs forged steel knuckle. Has nothing to do with metal inserts or the stresses they will see during operation....but it does talk about different metals.

Maybe you need to read and understand what you are trying to use as proof before you submit it as such to prove your opinion. Yes, a forged steel knuckle will last longer than an aluminum one, we all knew that, but a forged steel knuckle with an aluminum insert in it will last just as long as a forged steel knuckle with a forged steel insert in it, as long as the insert is properly installed.

If the insert is properly installed, and the tie rod is properly torqued, there is no problem or fatigue, as there is no motion or cyclic stresses to cause fatigue.

Now, if the insert is not properly installed, or the tie rod is not properly torqued, then yes, there can be problems and failure, which is likely what you saw in the failure you claim to have seen.

You are more likely to see a knuckle failure than you are an insert failure unless it was installed horribly wrong.

Just because you think inserts are bad, doesn't mean they are. I respect your opinion, but it isn't law, and the link provided for proof does nothing to prove it in any way.

Using that link for proof would be akin to me comparing the relative strengths of delrin vs urethane vs carbon fiber, and then claiming if you put a rivet in them, the rivet will fail because it is a dissimilar material.


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LACK

I will make my point very simple.

An aluminum insert in a steel knuckle with a steel tie rod end will not last as long as just the knuckle properly sized and reamed.

A steel insert in a steel knuckle with a steel tie rod end will not last as long as just the knuckle properly sized and reamed.

Inserts are a band aid solution and you're comparing a bolted connection with your lug nut and wheel analogy.

That link I provided compared the strength of knuckle materials, now youre talking about adding a 3 dollar insert to an already engineered and well designed system to act as a band-aid or cheap fix. I stated its a failure point, and yes, the fact that in most cases these inserts are aluminum/steel (a dissimilar metal from the knuckle) is the failure point.

TRCM

If the insert is steel, and the knuckle is cast or forged steel, how the heck is it dissimilar ???

1) a tie rod end IS a bolted connection as well, it simply has the benefit of a taper to minimize relative movement in most planes

2) even if the insert was the SAME exact material, it would be just as likely to fail....it is in a static condition and therefore no cyclic stresses...therefore no fatigue....therefore no failure.....as long as it is properly installed and torqued.

3) the fact that the insert is 1 metal and the knuckle is another has nothing to do with failure, unless there is corrosion involved....unless something is not installed properly and allows movement between the tie rod stud, the insert & the knuckle, it will last just fine.

4) If your logic of it being a dissimilar metal being the reason it fails in a static environment, then I guess we need to look at grade 8 fasteners & washers, as they are NOT installed in grade 8 parts (some are even used with aluminum & cast iron), yet they still work just fine.


I do agree, a properly tapered knuckle would be better, but not everyone can go that route, and using inserts is a perfectly acceptable way to do things as long as the installation is done properly.



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