I've read posts that suggest that suspension modifications--particularly springs/mods that reduce stock height--damage other suspension components or shorten their life.
What sort of damage can result?
Is it a matter of degree, i.e. small drops (TRD, for example) don't stress the suspension as much as do radical drops?
Dropping height is mostly done for appearance reasons, as opposed to handling performance?
Thanks all.

 

It is true. The lower the car the more stress you add to other suspension components. Bushings and ball joints will start to wear faster, you will blow your shocks and stuts if you're too low due to bottoming out (follow manufacturer specs on minimum and maximum drop), and wheel bearings will go out and tires will wear faster if your alignment isn't corrected.

If you have a minor drop( 1"-1.5" ), there isn't much to worry about. It's when you go extreme (2.5" and lower) is when you have to worry about the other suspension components being damaged.

Most people lower their cars for appearance reasons. No one likes wheel gap, so the get a set of springs and or dampers to solve that issue. Then there are those that lower their cars for handling. The ones that lower for handling usually have other suspension components that work in conjunction to their drop to achieve the handling that suits their driving style.

 

The sooner you drop the better cause the shocks and struts haven't started their wear patern yet. If you plan only an inch drop you shouldn't notice any premature wear on anything. You also shouldn't need an alignment cause there isn't enough geometry change to mess it up. I went 1.5 drop with no ill effects.

 

These are all reasons i went with the TRD setup from the dealer.

 

anything that you do that involves loosening the the front struts will require an alignment that is if you care. the strut mounting holes (particularly the lower ones) are larger than the mounting bolts because alignments are performed by shifting the struts around in their mounts then tightening them into place. i just adjusted my camber that way last night. that is also how the toyota manual says to do it. camber mounts would be nicer :/

that said, i ran with progress springs for at least a month before getting my car aligned last year. i didn't have any big problems, but i was still running stock steelies back then.

i don't know about other components, but you will wear the dampers faster as scibox wrote.

 

WHAT???? If you had truely read the service book you would know that the lower 2 strut bolts determine the camber and as long as you keep the same bolts in their place, camber will not be affected just because you change out springs. They make different offset bolts if camber does need to be adjusted.
With a mild drop you should never need an alignment unless you want some extra piece of mind. I've swapped springs several times and haven't needed an alignment yet and my tires wear even with no problems.

 

^^ yes, bolts are used to adjust camber only when it is to be adjusted outside of the range available by shifting the strut around in the lower mounts.

when you change out the springs, then you MUST remove the struts thereby loosening the lower mounting bolts. when you put it back together, the only GUARANTEE of the degree of camber is within a RANGE (maybe half of a degree).

i just adjusted my camber by about one quarter of a degree last night.

it is covered at 26-9 of my manual (pdf) section 7: adjust camber.

i am done with this thread. if anyone wants a copy of the front end alignment pdf from the manual, then PM me with your email address.

 

I concur with the 1-1.5" drop , should yeild no ill effects (thus TRD , or Eibach Pro line.. or the H-tech Tein, etc.) , but from what I've noticed over the years.. and talking to tire/suspention alignment guys... once you get close to 2", or 2"+ .... thats when your playing with fire. It might give you the "look" you want, but 1. it wont handle very good , 2. it will slowly wear other suspention parts prematurely.

just my .02 cents