Is it true that new suspension parts wear out old parts faster?

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I have an SUV with over 130K miles and so far I'm going to replace the upper control arm (which comes with a ball joint) as well as the inner and outer tie rod ends since all these components have damaged & worn boots. The lower ball joint boot seems ok but I don't know if I'm taking a risk not changing it along with everything else.

Now I've seen it mentioned in various places that new suspension parts really stress out older parts. My question is, how often have you found it to be true?
 
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If it's in good shape, there's no harm leaving it, unless it requires removing it to do the other work in the first place. Then I'd stick it in the 'replace while you're in there' category.

Ball joints don't have any give to them, so its not like you're leaving a worn out rubber bushing in there, which could cause premature wear on new components if that were the case.
 
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No, unless you somehow stress or damage the old parts during installation of the new.
 
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An old time mechanic once told my dad (in the mid 1960s) that a car worked better with all old parts rather than with some old parts and some new parts.
I believe that to be true in some cases. For example, on a worn engine, you pull the head and have a valve job done. Before, the rings and valves had a less-than-perfect but acceptable seal. Now, with the valves sealing well, that puts more pressure on the worn rings, and they leak more than they did before.

I don’t think this would apply to suspension parts.
 

Kestas

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I heard worn out shocks can affect suspension components. New shocks don't allow as much movement in the suspension components as worn out shocks.
 
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Is it true that new suspension parts wear out old parts faster?​


No! Worn out suspension parts potentially hammer the other parts that they are connected to. So just replacing the worn out parts reduces the "slop" and actually makes life easier on the other left over old parts.
 
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I've heard it from old timers, and I can understand the basic logic behind the theory. That being said, I think what actually happens is one component is fixed, and it makes how much the other components are worn out must more obvious. So the new part didn't necessarily cause the failure of the other one, it just made the failure more apparent.
 
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I can see that happening. The new parts are not absorbing any of the flex the old parts were, so the old parts that are left on the car are now absorbing all of it. Just a theory.
 
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... on a worn engine, you pull the head and have a valve job done. Before, the rings and valves had a less-than-perfect but acceptable seal. Now, with the valves sealing well, that puts more pressure on the worn rings, and they leak more than they did before.
That's true. In the '60s doing a valve job was quite common. If you didn't replace the rings at the same time an engine could start to burn oil, or at least burn more oil.
 
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