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david in germany
01-06-2010, 10:03 AM
Ok, I kinda elevated a discussion on another forum with a guy that believes he is the master of worldly info. The discussion was basically aftermarket springs will kill stock struts. My side of it is that the springs cannot kill stock struts, when a struts time is up it is up regardless if it is aftermarket or stock. My Celica was running stock struts on H&R springs issue free for almost 180k miles but this dude swears that my struts were bad and I just didn't know it. ( I have done all my maintenance myself on my cars all my licensed time of over 20+ years and DO know the symptoms of a blown strut)

I have researched on numerous spring manufacturers and have not found a single one recommending changing from stock struts on the install of their springs. As far as I can tell about 99% of aftermarket struts (excluding coilovers) are built to meet stock specifications and have the same measurements as the stock struts, therefore, there would be no benefit to switching them out.

Discuss.

Does anyone have any proof that Aftermarket springs will kill stock struts?

Shadowlife25
01-06-2010, 11:12 AM
MetDeath will likely chime in as will Luni probably....

I just want to say this:

LOWERING/DROP SPRINGS WILL cause premature failure of a strut that is OEM.

Reason being that the strut is never able to go through the complete bound/rebound cycle and is not able to build the necessary internal pressure to properly dampen due to lack of travel.

Will it kill them within a year or 3 even? NO

It will simply cause unfavorable ride characteristics and premature failure. (5 years?)

Premature compared to a stock OEM setup that usually will last 10-15 years.

I hope this makes sense.

grayscale
01-06-2010, 12:21 PM
I think it also depends on how you use them and what your daily driving conditions are. I already have a blown kyb gr2 on my eibach pros, driver front. However, they have seen a lot of hard driving and some pretty bad bumps. I'd say less than 40k miles. Like Mario said, it has suffered premature failure due to not being able to properly dampen some of those really bad bumps. Had this been your average DD on average okay roads, it would probably be fine.

david in germany
01-06-2010, 12:30 PM
I have personally never heard of anyone having problems with stock struts with aftermarket springs (over 170k miles on the celica with stock struts). I have heard of people having issues with aftermarket struts with aftermarket springs though.

My driving style is hard too and as I mentioned before I NEVER had any issues with stock struts and aftermarket springs.

My line of thought on this is, the ride position is just under the original height but the full travel can still be obtained, aftermarket springs are not shorter they just settle lower so the travel is not reduced at all. If the springs were in fact shorter than stock springs then they would come out of the perch on full travel of the suspension.

balang_479
01-06-2010, 01:41 PM
I've got Eibach lower springs on stock struts... I have clunking in the rear suspension but i dont know if its the struts or the bushings...

But the front is fine and i drive it hard.

david in germany
01-06-2010, 01:48 PM
I've got Eibach lower springs on stock struts... I have clunking in the rear suspension but i dont know if its the struts or the bushings...

But the front is fine and i drive it hard.

Had that issue too and it is normally the sway bar bushings. $10-12$ fix. :)

Futant3
01-06-2010, 03:22 PM
Your idea of spring expansion versus sitting position sounds logical enough. I know that strut makers give guidelines for acceptable lowering amounts, and void warranties if you are out of range on it. Don't remember seeing the spring makers say anything.

I'm wondering if lowering the normal compressed position makes the pressure level in part of the strut higher than normal for those large amounts of time at sitting level. Thus you are also going through a different range of pressures than normal when the spring compresses/decompresses. Possibly causing the premature wear but also allowing for some variance in lowering rates.

Just thinking out loud.

METDeath
01-06-2010, 05:46 PM
Basically, the ride quality goes to shit when you drop it too far with too stiff a spring, because the spring does more of the suspension work that it is supposed to. This either happens because of the lack of travel due to too much drop, or due to the spring rates being too high for the stock strut. I got lazy doing my first spring install (no pipe wrench at the time) and ran whatever strut was on the front of the car with my Eibach Sportline springs, it still dampened just fine when sitting still, and would operate like normal. However, on the road with some of the harder suspension travel it would bounce two/three times depending on the severity of the road.

I think if KYB made an adjustable strut for our cars, I may have bought those first time around, since those are decent for a street car. However, they don't so I went with Koni struts. So some would argue that getting a coil over kit makes more sense... but that's not this thread. Basically the issue I had with the Sportline/KYB combo was that when the suspension would get close to it's limits, my car would start "skipping" instead of the tires squealing. Once I got the Koni struts in, the issue went away.

So, does an aftermarket spring require an aftermarket strut? I don't think so, but it will help if they're available.

rev_head
01-06-2010, 09:27 PM
Theres heaps of relative factors on people who have or havent had complaints. how worn the shocks previously were, how much lower the spring rate is and of coarse as pointed out how hard it gets driven.
a big height drop spring will undoubtably put more strain on the shock. The big drop springs are physically shorter. consequently the shock is continually compressed and is working even when at a stand still. the one saving grace is usually dramatic lowering springs have a soft spring rate so the shock isnt strained like crazy in hard driving conditions.
as i said about what condition the shox are in? lets be honest 80% of people that use lowering springs wouldnt bother/know wether ther sock is good or not they just care about the fully sick image (of coarse none being celica owners where to smart for that). a shock can be damaged and still rebound but i guarantee for the bulk of us if we compared our shocks to a new one we would realise the shocks already prity worn.

anywayz yer depends but shadowlife has it when he says the OEM shocks will fail sooner with lowering springs, no one can argue with that...............unless they drive a honda haha

Okctrd
01-07-2010, 01:54 AM
when i installed my sprint 1.5 springs i decided to leave the stock struts and about 6 months later the ride quality got harsh.

When i pass on bumps it sounds like something has broken off the car or something.. and it thumps in the back. (probably bushings for the rear??)

i know it wasn't like this before i lowered it.. (213k)
so, i guess i blew the stock struts...

so yea i need to get new struts and rear bushings..

KoreanJoey
01-07-2010, 05:22 AM
Yeah David... With a 170k on the struts I'd be more than willing to say they're probably blown. They might leak but I'd be willing to bet the internal valve is shot.

Best check is the rebound check. Take off a strut, remove the spring, compress the shock and see if it comes back under it's own power, also check that if you pull on the strut it should try to fight against it.

But generally speaking... the valving on Toyota shocks doesn't last more than maybe 100k or so before the internal valve starts to crap out.

Ricksta
01-07-2010, 06:04 AM
when i installed my sprint 1.5 springs i decided to leave the stock struts and about 6 months later the ride quality got harsh.

When i pass on bumps it sounds like something has broken off the car or something.. and it thumps in the back. (probably bushings for the rear??)

i know it wasn't like this before i lowered it.. (213k)
so, i guess i blew the stock struts...

so yea i need to get new struts and rear bushings..

well man your ride is 20 years old what do you expect?

i did a lot of research before i spent the cash on the upgrading my suspension back in the day. i went with the kyb struts with eibach springs 1" drop.

from what i was told i cant remember if it was 1.5 or 2 inches but i was told there would be no damage to the strut as long as i didnt go any lower than 1.5-2 inches on a stock replacement like that.

rizin
01-07-2010, 06:27 AM
I doubt the shorter stroke is the big deal. Look at a car driving next to you. you will notice that the shock does a lot of short movements. I think it has to do more with the higher spring rate putting more pressure on the rebound valving of the shock. It would be oppisite for in the other direction.

So to me the stock strut might fail early beacuse they were not desgined for the higher pressures put on the valving. The after market ones could be built with the same compression and decompression rates as stock but could be built for the higher pressure. I think of it like cast pistons they could do it but to much pressure they will fail. Then you put in forged they do the same job but can handle a higher pressure.

My thinking might be wrong but just throwing it out there.

david in germany
01-07-2010, 06:52 AM
The big drop springs are physically shorter.

Incorrect, a phisically shorter spring would pop out of the stock perch on a complete travel of the suspension. The phisical size of the springs cannot be different.

To all that wonder, here in Germany we MUST go through yearly inspections to register the cars. The inspectors put them up on a suspension machine to ensure serviceability of the running gear. I can guarantee you that my struts were still 100% functional. No bouncy rebounds, no leaks ect.

grayscale
01-07-2010, 11:56 AM
Uh, I may have to argue that. When I installed my eibachs, I needed spring compressors to remove the stock springs, but I didn't need to compress the eibachs- strut hat dropped on and plenty of threads were sticking out.

david in germany
01-07-2010, 12:03 PM
Uh, I may have to argue that. When I installed my eibachs, I needed spring compressors to remove the stock springs, but I didn't need to compress the eibachs- strut hat dropped on and plenty of threads were sticking out.
That is not a good thing.. There should have been tension in the install. I ran Intrax, H&R, and Eibach on the Celica and all had at most 1" difference at full length. I can see less tension because of the varying rates of the springs but being able to just stick them on teh struts without the needed tension is a bad thing ( as the springs will soften over time and come out of the perch is there is not enough tension):(

METDeath
01-07-2010, 03:24 PM
As for springs being shorter... well, I had to use a spring compressor to remove my stock springs, but when assembly them again with the Sportline springs (1.5" drop), the rears just slide together with no compression, and the fronts only take a little compression to get assembled. Hell, with the Mario/vert fiasco he and I disassembled a rear gently pressing the spring down by hand and that was to just keep it from flying around on us.

rev_head
01-07-2010, 08:55 PM
well i have put stock and lowered springs side by side before and they were physically shorter!
basically everyone i know who has installed lowering springs will tell you the same, why else would everyone be saying they had to compress the stock springs more then the new ones for fitment? also dont forget there is such a thing as captive and non captive springs

rizin
01-07-2010, 11:27 PM
That is funny my brother back in high school lowerd his geo storm(what a waste). He had to make clamps that held the spring to the struts. I guess that is what you get when you go to low.

88st165
01-08-2010, 12:37 AM
Thats strange. All lowering springs Ive installed needed a spring compressor. B+G, Intrax, TRD for st165 needed to be compressed. Only eibach kit Ive installed was for a 2g eclipse and it also needed to be compressed.

No need for a compressor would be awsome! Those springs must be really really progressive haha

KoreanJoey
01-08-2010, 07:41 AM
My GCs would unseat at full travel... The Konis on full stiff prevent that though. :)

PS: Limiting straps are cheap.

85gtsblackman
01-09-2010, 02:50 PM
my h&r springs give a very light bounce going over bridges and other sectioned road ways, i may see about getting better shocks for the front although when i took the assembly apart they had plenty of life left, rears are squishy though. car still coners better than stock

METDeath
01-09-2010, 08:56 PM
Limiting straps?

donteatbugs
01-13-2010, 06:52 PM
it straps the strut down to the springs full extended length and wont let it unseat a short spring.

i have koni/ gc on the alltrac. one blown strut so far.

METDeath
01-13-2010, 10:19 PM
Actually, I was more inquiring where I would find them, even though I don't three wheel, I do jack my car up on a semi regular basis and would like one less thing to worry about.

KoreanJoey
01-15-2010, 04:35 AM
Look for offroad parts. They'll almost always have them.