Life of stock LGT shocks?

[Legend]

Good finds, schwinn!

 

I've suspected either my struts or shocks need replacing but I have't been able to determine which, if either, needs replacing. My car has 68k now and the ride has just seemed a little rougher all the time. The previous owner and I both have tracked it and it has had a modified suspension most of its life.

 

The most obvious tell-tale sign for me though is that sometimes at low speeds bumps or tight turning cause noises (like bottoming out and I also hear the tires rubbing on something). This didn't happen 2 years ago.

 

The car will be on a lift tomorrow for a wheel bearing and 4-wheel alignment... I'll see if I can see anything interesting..

[Scotty]

well then I've got all you guys beat! I've got 134k on mine and my stock suspension is ok. every now and then going over speed bumps I hear some noise, but other than that they are fine.

 

even had my subie mechanic give me his opinion and he agreed with me.

 

No you don't. I got you beat at 150K.

[NatesGr8]

about 107K on mine and suspension feels fine, i've had cusco sways since 1,000 miles, now the water pump on the other hand, that is questionable...

[JoeFromPA]

Completely different, but my 06 Civic SI has 81k miles on it and I think the dampers are fairly shot. Harshness comes in more than ever, the car doesn't take a set like it used to, and I get noise going over speed bumps at very low speeds.

 

But ya know what? They still get the job done. Nothing is breaking or making god awful noises. I just don't have the ride quality or handling I should.

 

I think this is what most people refer to as a damper being shot. It doesn't damp well anymore.

 

I can probably run like this for another 70k miles or so. Just a matter of how long you intend to keep the car and the type of ride and handling you want.

[Crossing509]

After much research, I've decided to purchase Koni struts and pair them with a spring that gives a conservative drop (+/_ 1"). Just tired of the sloppy stock suspension and the more I read about suspension mods the more I got tired of what I have. I figure koni struts + new springs + super pro LCA bushings + Whiteline roll center kit should equal a great improvement. Can anyone recommend springs for a 5EAT with this setup? I'm not looking for that "slammed" look since I have to deal with poor roads and lots of snow. I'm leaning towards Rallitek, Eiback, or Ions (but I can't find Ions anywhere ).

[naimouasta]

^ you won't be disappointed. i don't even know why some of you guys are even talking about the stock shocks/struts. front is ok, but the rears are so so underdampened it might as well be dead to begin with.

[mwiener2]

After you are all done bashing the "bounce" technique, anyone wanna find a better way to test the shocks without removing them from the car?

[naimouasta]

measure wheel gap after your normal drive. then measure it again after one night of parking. if there is less wheel gap then the struts are dead. not 100%, but it worked for me.

 

didn't even measure my dads forester before i did it, but you can definitely see a difference visually. no more sagging. also same scenario when i did my aunts toyota sienna. it was a bitch, i had to use 4 spring compressors. long ass springs. after i was done with the sienna it was a monster truck.

 

and the general consensus i get from the forum is that the stockers start to go between 40-60k, and worst if you're on aftermarket springs. i may be wrong .

[mwiener2]

I'm at 85k with my OBXT. Trails and Track. Mine are soft, but hardly dead.

[Legend]

After you are all done bashing the "bounce" technique, anyone wanna find a better way to test the shocks without removing them from the car?

 

Probably not a better way. The "bounce" technique is probably all we got... but it appears to only be a marginal indicator.

[mwiener2]

measure wheel gap after your normal drive. then measure it again after one night of parking. if there is less wheel gap then the struts are dead. not 100%, but it worked for me.

 

 

Shocks are really dampers. They aren't meant to support weight, just absorb energy. If you sag overnight, that's more indicative that your springs are shot, not the shocks.

[naimouasta]

^ i know they are dampers. its just an observation i made twice, so i don't really have an explanation for it. after the replacements, no more sag. you said stop bashing techniques so just trying to help.

[mwiener2]

did you replace springs as well?

[naimouasta]

no, not for the forester or sienna.

[mwiener2]

if you take a shock without a spring on it, it will stay in whatever position you put it in

 

 

edit: I take that back, kinda. Nitrogen filled shocks are under some pressure and may help out the springs a bit.

[naimouasta]

+1 yea now that i remember when i put the koni's on, they stayed in whatever position i put them, where the stockers would push back up. the "dead" struts in the forester/sienna stayed in whatever position also, but had no sort of resistance at all so they were indeed dead. i think my ride height test is valid for certain type of struts/shocks.

[schwinn]

After you are all done bashing the "bounce" technique, anyone wanna find a better way to test the shocks without removing them from the car?

Sorry mwiener... I didn't mean to take it all out on you, just presenting the facts that I have seen and heard... anyone can feel free to prove me wrong, if they have better info. But, I can believe the data presented, since it basically says that a bounce test doesn't stress the strut in the same way (due to travel rate, etc).

 

Bottom line, I'm not blaming you or whatever... you just happened to be the person to post the bounce test info... that's all.

Shocks are really dampers. They aren't meant to support weight, just absorb energy. If you sag overnight, that's more indicative that your springs are shot, not the shocks.

Agreed, shocks aren't supposed to support weight... but, here's how I see it:

 

I believe struts are more heavily gas-charged, and hence have a stronger extending-force (than a shock). If this force is degraded, the strut is clearly leaking by its seals internally, at least. This can be seen as a reduced height, since that force is normally helping to suspend the car.

 

So, although the strut isn't supposed to be springing-the-car, the force it imparts will cause the vehicle to rise, and so if it rises less, then the strut could be leaking by/worn... right?

 

As you noted, nitrogen charged shocks will also cause some "lift" in the car in the same way... but if the charge (force) isn't significant, then it won't lift the car much... so it may not be as visible there.

 

As for your first question... I believe they have on-car test pads that can exercise the vehicle appropriately, to see how the struts are. Kinda like doing a shock-dyno while they are still installed on the vehicle. Here is a company that does this type of testing, and has a nice list of different test methodologies and their pros/cons: http://www.hunter.com/pub/UnderCar/4187T/index.htm

 

Check out their pad-based "Hunter SA400 Suspension Analyzer" and the picture at the end...

[mwiener2]

I fully agree that the "bounce" test is not the best way to go about it... but it pretty much is the only way.

 

I have NEVER seen or heard of shop that has a suspension tester like that in it.

 

 

 

I'd also like to point out that the only difference between a shock and a strut is the placement of the parts. A strut is a shock that sits inside the spring and is a complete assembly. Traditionally a "shock" means that the spring is seperate.

 

Struts can be under pressure or not, completely depends on what particular damper is installed in it.

 

 

Basically to sum up this thread... Unless you go to a place that has specific equipment to test suspensions, there really isn't a good way to test your shocks. If they're leaking, they should be replaced. If you feel like you got your money's worth out of your shocks (50k+ miles), then you could probably replace them without feeling like you're wasting money.

[Legend]

Basically to sum up this thread... Unless you go to a place that has specific equipment to test suspensions, there really isn't a good way to test your shocks. If they're leaking, they should be replaced. If you feel like you got your money's worth out of your shocks (50k+ miles), then you could probably replace them without feeling like you're wasting money.

 

Agreed.

 

My car is at the shop right now... I paid for a complete inspection ($21.99) top to bottom and on the lift. They found plenty of items (like "oil not topped off", battery terminal corrosion, cracked axle boot, front wheel bearings (being replaced), but they made no comments on my shocks or struts. So.. no visual signs of all-out failure, but I'm sure a fresh set would feel nice. I'll pass for now.

[JoeFromPA]

I've only ever experienced one car that I'll define as getting a true full-blue suspension upgrade: my father's 99 boxster.

 

At 8 years of age and 55k miles, he replaced the stock dampers with new bilsteins. He put braces on the front and rear. And he installed a set of Michelin Pilot Sports all the way around.

 

Now, due to getting bilsteins and Michelin Pilot Sports all at once, I have no idea what did what where.

 

But I have never, ever driven a car that handled that well and rode so smooth with such great steering feedback, as that Boxster had after that swap. The tires definitely had something to do with that, but the way the bilsteins damped bumps within the short travel of that suspension tells me that a refreshened suspension setup can work wonders.

 

Just my one experience with a nice replacement of new OEM-fitment dampers on a car that didn't seem like the OEM dampers were shot.

[mwiener2]

so now we're comparing Porsches to Subaru's? The Boxster only has suspension... you certainly aren't buying it for the power. It's a glorified Miata.

[JoeFromPA]

Wow, ass.

 

No I wasn't comparing it to the Subaru. I was making a general commentary on my sole experience with a low-mileage car that had no signs of the suspension being poor, and upgrading them with an OEM-style replacement (rather than a coilover or performance oriented spring/strut replacement). The difference was dramatic, albeit complicated by other factors.

 

Also, it's great that you think in terms of the Boxster being a glorified miata. You are an enlightened individual. I take back 25% of my prior defenses of you

 

Joe

[schwinn]

Basically to sum up this thread... Unless you go to a place that has specific equipment to test suspensions, there really isn't a good way to test your shocks. If they're leaking, they should be replaced. If you feel like you got your money's worth out of your shocks (50k+ miles), then you could probably replace them without feeling like you're wasting money.

Quite true...

 

Incidentally, this page has some interesting info: http://www.smithees-racetech.com.au/performancefactors.html

 

Granted, they are sizing the strut/shock for an un-dampened vehicle to start with, then choosing from there. However, I imagine there must be a good way to mathematically generate similar data from a car, and determine if it's "good" or not? I'm not saying I have a formula to provide, but I imagine it could be done?

 

As for shocks versus struts... I agree I don't know for sure if one is "charged" more than the other. I just know that my shock-setup vehicles had non-charged shocks (stock) while even stock struts have always been charged... in my experience. The implication would be that a "performance" shock or strut might have increased gas-charge than the stocker... and assumption by me, of course.

[mwiener2]

Wow, ass.

 

Also, it's great that you think in terms of the Boxster being a glorified miata. You are an enlightened individual. I take back 25% of my prior defenses of you

 

Joe

 

 

Sorry, didn't intend to make that a personal attack. But common... it's a Boxster. You really can't argue that it's not a glorified Miata.

 

They do handle really well.

 

 

 

 

Incidentally, this page has some interesting info: http://www.smithees-racetech.com.au/performancefactors.html

 

 

Practical for racing, not at all for street. That also seems like "their thing" versus an industry standard or something. I dunno.

[JoeFromPA]

Hmm, well I guess I can argue it. It's a mid-engined semi-luxury car with a great flat-six engine (albeit with some serious reliability concerns).

 

It is a modestly powered 2-seater RWD car built for handling. Aside from that, they are fairly dissimilar cars.

 

I guess the BMW 535xi 6-speed wagon is just a glorified Outback XT? I mean, how far do you want to take that sort of logic?

 

Joe

 

P.s. I've looked into the potential to swap a LGT/WRX engine into the Boxster since they are both 2.5 liter boxer engines. Seems doable, though no one seems to make the necessary adapter parts. Boo ....that 2800 pound car would be a blast with a tuned up engine.