2nd new suspension setup- still rides bad

[sebastian]

Weird suspension issue- I had new bilsteins 5100s with 883 ome in the front and 895e in the rear for a year, then bam, all this sway, bumpiness bump steer just started happening- lower control arms, links replaced, multiple shops said all is good down below.

I lost my mind, 4 months ago got new ome shocks 900021 and 60004 , now im bumping and flying all over the road-

so my question is, is pre-loaded suspension a real thing?- was the suspension somehow installed preloaded so my ride is more bouncey, not floating but like i go up and down (springy) on small bumps.

I do have 275 65 18 k02's on my 08 with a mix of 35-40psi but none of that mattered, drives like crap now.

 

[Inv4drZm]

You can't really install the suspension wrong, its pretty basic in operation.

Double check your alignment and play around with psi a bit more maybe try 30psi.

 

[waypoint]

(NOTE: This is a very simple summary of an entire chapter on racing car chassis setup). Preload usually applies to either swaybar geometry or cross-corner load distribution. The swaybar is basically a linear spring designed to transfer force from one suspension point to another. If it is preloaded at neutral vehicle position, it will transfer force in strange ways when force is applied to one wheel. For example, if the bar is preloaded on the driver's side it will be applying upward force to the passenger side wheel...and will cause unusual behavior during cornering or bumps.

If your suspension setup(s) raised the front suspension height, it's possible that the swaybar is either preloaded (if both control arms weren't raised to the same new height) or the force is being applied from the control arm to the swaybar at a non-optimum angle. You generally want a 90deg angle between the swaybar and end link, and if you look at stock suspension pics you'll see that's where Toyota puts it from the factory. This causes the force of the control arm to twist/rotate the swaybar. As the suspension height increases, the distance between the swaybar horizontal surface (chassis bushing mounts) and the lower control arm increases, thus increasing the angle of the swaybar ends and the endlinks. This causes the force of the control arm to push the swaybar horizontally against the bushings, and affects the transfer of force between the front wheels.

Cross-corner load distribution can also be affected by swaybar preload, or by differences in net spring force applied to the wheel. The latter can be caused by vehicle weight distribution (more weight on the passenger side than driver side, etc.) as well as suspension geometry (net spring installed height variation between sides due to damaged/deformed spring perches, etc.).

I'd start with a visual inspection of your swaybar geometry as described above, then measurements from ground to apex of fenderwell at all 4 corners to check for ride height variation.

 

[sebastian]

Thanks for the answers- i definitely feel something different after a lower control arm was replaced a few weeks back since the newer-ish one failed- good call about sway bar- and after the recent alignment it does feel more sway-like side to side. Interesting points- ill check out the sway/links if they are 90 degrees

 

[sebastian]

attached is my alignment specs from the shop

(NOTE: This is a very simple summary of an entire chapter on racing car chassis setup). Preload usually applies to either swaybar geometry or cross-corner load distribution. The swaybar is basically a linear spring designed to transfer force from one suspension point to another. If it is preloaded at neutral vehicle position, it will transfer force in strange ways when force is applied to one wheel. For example, if the bar is preloaded on the driver's side it will be applying upward force to the passenger side wheel...and will cause unusual behavior during cornering or bumps.

If your suspension setup(s) raised the front suspension height, it's possible that the swaybar is either preloaded (if both control arms weren't raised to the same new height) or the force is being applied from the control arm to the swaybar at a non-optimum angle. You generally want a 90deg angle between the swaybar and end link, and if you look at stock suspension pics you'll see that's where Toyota puts it from the factory. This causes the force of the control arm to twist/rotate the swaybar. As the suspension height increases, the distance between the swaybar horizontal surface (chassis bushing mounts) and the lower control arm increases, thus increasing the angle of the swaybar ends and the endlinks. This causes the force of the control arm to push the swaybar horizontally against the bushings, and affects the transfer of force between the front wheels.

Cross-corner load distribution can also be affected by swaybar preload, or by differences in net spring force applied to the wheel. The latter can be caused by vehicle weight distribution (more weight on the passenger side than driver side, etc.) as well as suspension geometry (net spring installed height variation between sides due to damaged/deformed spring perches, etc.).

I'd start with a visual inspection of your swaybar geometry as described above, then measurements from ground to apex of fenderwell at all 4 corners to check for ride height variation.

anything off with this alignment, i don't have a huge lift as mentioned 883 in front and 895e rear

 

[dawudih]

Yesterday I removed my Bilstein 5100's after 4 months & went back to stock with a very small front spacer (0.4") to help level it a little. Soooo much smoother & good alignment specs now.

 

[DZNUTS]

(NOTE: This is a very simple summary of an entire chapter on racing car chassis setup). Preload usually applies to either swaybar geometry or cross-corner load distribution. The swaybar is basically a linear spring designed to transfer force from one suspension point to another. If it is preloaded at neutral vehicle position, it will transfer force in strange ways when force is applied to one wheel. For example, if the bar is preloaded on the driver's side it will be applying upward force to the passenger side wheel...and will cause unusual behavior during cornering or bumps.

If your suspension setup(s) raised the front suspension height, it's possible that the swaybar is either preloaded (if both control arms weren't raised to the same new height) or the force is being applied from the control arm to the swaybar at a non-optimum angle. You generally want a 90deg angle between the swaybar and end link, and if you look at stock suspension pics you'll see that's where Toyota puts it from the factory. This causes the force of the control arm to twist/rotate the swaybar. As the suspension height increases, the distance between the swaybar horizontal surface (chassis bushing mounts) and the lower control arm increases, thus increasing the angle of the swaybar ends and the endlinks. This causes the force of the control arm to push the swaybar horizontally against the bushings, and affects the transfer of force between the front wheels.

Cross-corner load distribution can also be affected by swaybar preload, or by differences in net spring force applied to the wheel. The latter can be caused by vehicle weight distribution (more weight on the passenger side than driver side, etc.) as well as suspension geometry (net spring installed height variation between sides due to damaged/deformed spring perches, etc.).

I'd start with a visual inspection of your swaybar geometry as described above, then measurements from ground to apex of fenderwell at all 4 corners to check for ride height variation.

While I’m on the same page you’re on (my background is road courses and autox) the question is, what is the best way to retain the sway bar end link alignment while maintaining the 3” front lift.

On a side note, I can’t wait to get new springs so I can remove the preload in my front springs (5100s and FJ springs set at 2.5”) and improve overall ride (although not terrible)


Sent from my iPhone using Tapatalk

 

[sebastian]

You can't really install the suspension wrong, its pretty basic in operation.

Double check your alignment and play around with psi a bit more maybe try 30psi.

So after driving it a few weeks i'm starting to think this tight bouncy up and down issue is after the alignment, is it possible things were tightened in the new alignment?

 

[Keros]

Keeping in mind I'm no expert by any means.

The alignment would induce how the truck feels through the steering wheel, and road feedback. Essentially, how it tracks down the road and feels through a corner. For instance, if castor is set too low it'll feel like the steering wheel isn't connected to anything and it's like driving a playstation controller. The alignment changes dynamically as the truck moves and weight inside changes, so what comes out on the rack is only pretty close... out on the road in the real world, those specs change slightly as the suspension moves. Ideally, when you're on a flat, level surface, with the same load in the truck as when the alignment was done, those specs should be REALLY close to what you'd find (if a guy could measure that accurately). Anyway, that's neither here nor there, just something to keep in mind.

How the truck sways back and forth is a combination of spring rates of the 4 corner's springs and the sway bars. And further, if the endlinks and bushings for the sway bars are shot the truck can feel sort of "wobbly", and the faster you go the more pronounced the "unsteady" feeling will get. This happens because the worn out bushings give enough play that the anti-sway system isn't engaged for minor suspension movements... the small adjustments we are making in the steering wheel to go down the road are being absorbed by the slop in the bushings, and thus, the chassis is able to sway back and forth unrestricted by the sway bar (which is doing nothing). I bring this up because if Camber is in spec but the truck feels unsteady, not "sure-footed", "unplanted", etc; it's probably a sway bar bushing is worn out.

The up/down motions of the suspension would be entirely spring rate and shock dampening driven. If you hit a speed bump and the truck attempts to throw you out the roof... no alignment changes are going to effect that (I don't think).

Primarily, if the truck dives hard on braking, you see sky on accelerating, and it bottoms out easily on bumps, ramming the chassis off the bump stops... the springs are too soft.

If the truck thrusts upwards violently during big bumps (like overly large speed bumps), feels like you can personally relate to every crack in the road and manhole cover because your spine is being compacted by them... and generally the truck is uncomfortable to ride in because you're getting banged around alot, springs are probably too stiff.

There's a thread somewhere on all the spring specifications common for the 4th gen. The OME stuff tends to be pretty heavy duty for banging around in the bush with heavy loads of gear. Someone jump in and correct me here if I'm wrong, though. Staying real close to stock if your truck is close to stock is ideal. As your truck gets heavier, your springs will probably need to as well... ride height can be fixed with spacers, but the spring still needs to support the weight.

If the truck is bouncy, as in the truck oscillates up and down repeatedly after a big bump, then the shocks are not dampening the spring properly. Essentially the shocks are too weak for the spring. If you get on a running board (and you're +/-180lbs), you can probably get it bouncing pretty good. The truck should settle quickly once you jump off. I think it's like 2-3 bounces it should be settled. Anything excessively more than that could indicate the shocks are blown or inadequate for the spring.

An overdampened spring is a little bit harder to pick out. A shock is always trying to resist the spring from bouncing (or contracting at all, infact). So, having too much shock and not enough spring... I think the truck may feel much like the springs are too stiff, but it's a bit different. Like, the truck will dive normally, but then shoot back up to normal ride height, then the bounce crests, and remains at peak ride height. No bounce and settle... just BOOM back up to ride height.

Having said all that to try to get a sense of what all the up and downs of suspension are (haha, I slay myself!)... I think your springs are too stiff.

If I recall, pre-loaded springs are, and this would only be in a coil-over configuration like the front end, where the spring is mounted on the tube of the shock in such a manner that the spring is compressed significantly when the shock is not under load. I think in other words, with the coil-over (fully assembled) laying on the floor of the garage, the spring is already heavily compressed. I've been told this can make the handling pretty bouncy (as if the spring rates are too high [read:stiff]). No experience personally with this setup.

I think there's a narrow band of ideal spring rates that match a truck's specific corner weights... however, it also depends on what the end use of the truck is, as well. A family hauler will want softer springs and a dune jumper will need firmer springs.

And then the shocks should be valved to match the selected springs.

If your truck used to have air suspension the rear bumpstops may be too long for your new setup. Atleast, this happened to me anyway. I didn't see the problem talked about much so I guess it was kind of obvious to everyone (but me, lol)... And basically my truck was bashing the bumpstops constantly. Nice to put in a $3000 suspension system and give myself a chiropractic adjustment before figuring that one out.

Note that this is all off the top of my head, from things I read years ago, and hopefully helps bring some understanding to where the problem may be. And is in no way intended to be a comprehensive guide to suspension... stuff.

 

[feralcomprehension]

Keeping in mind I'm no expert by any means.

Maybe not, but you wrote a great summary. Rep points given!

 

[sebastian]

Keeping in mind I'm no expert by any means.

The alignment would induce how the truck feels through the steering wheel, and road feedback. Essentially, how it tracks down the road and feels through a corner. For instance, if castor is set too low it'll feel like the steering wheel isn't connected to anything and it's like driving a playstation controller. The alignment changes dynamically as the truck moves and weight inside changes, so what comes out on the rack is only pretty close... out on the road in the real world, those specs change slightly as the suspension moves. Ideally, when you're on a flat, level surface, with the same load in the truck as when the alignment was done, those specs should be REALLY close to what you'd find (if a guy could measure that accurately). Anyway, that's neither here nor there, just something to keep in mind.

How the truck sways back and forth is a combination of spring rates of the 4 corner's springs and the sway bars. And further, if the endlinks and bushings for the sway bars are shot the truck can feel sort of "wobbly", and the faster you go the more pronounced the "unsteady" feeling will get. This happens because the worn out bushings give enough play that the anti-sway system isn't engaged for minor suspension movements... the small adjustments we are making in the steering wheel to go down the road are being absorbed by the slop in the bushings, and thus, the chassis is able to sway back and forth unrestricted by the sway bar (which is doing nothing). I bring this up because if Camber is in spec but the truck feels unsteady, not "sure-footed", "unplanted", etc; it's probably a sway bar bushing is worn out.

The up/down motions of the suspension would be entirely spring rate and shock dampening driven. If you hit a speed bump and the truck attempts to throw you out the roof... no alignment changes are going to effect that (I don't think).

Primarily, if the truck dives hard on braking, you see sky on accelerating, and it bottoms out easily on bumps, ramming the chassis off the bump stops... the springs are too soft.

If the truck thrusts upwards violently during big bumps (like overly large speed bumps), feels like you can personally relate to every crack in the road and manhole cover because your spine is being compacted by them... and generally the truck is uncomfortable to ride in because you're getting banged around alot, springs are probably too stiff.

There's a thread somewhere on all the spring specifications common for the 4th gen. The OME stuff tends to be pretty heavy duty for banging around in the bush with heavy loads of gear. Someone jump in and correct me here if I'm wrong, though. Staying real close to stock if your truck is close to stock is ideal. As your truck gets heavier, your springs will probably need to as well... ride height can be fixed with spacers, but the spring still needs to support the weight.

If the truck is bouncy, as in the truck oscillates up and down repeatedly after a big bump, then the shocks are not dampening the spring properly. Essentially the shocks are too weak for the spring. If you get on a running board (and you're +/-180lbs), you can probably get it bouncing pretty good. The truck should settle quickly once you jump off. I think it's like 2-3 bounces it should be settled. Anything excessively more than that could indicate the shocks are blown or inadequate for the spring.

An overdampened spring is a little bit harder to pick out. A shock is always trying to resist the spring from bouncing (or contracting at all, infact). So, having too much shock and not enough spring... I think the truck may feel much like the springs are too stiff, but it's a bit different. Like, the truck will dive normally, but then shoot back up to normal ride height, then the bounce crests, and remains at peak ride height. No bounce and settle... just BOOM back up to ride height.

Having said all that to try to get a sense of what all the up and downs of suspension are (haha, I slay myself!)... I think your springs are too stiff.

If I recall, pre-loaded springs are, and this would only be in a coil-over configuration like the front end, where the spring is mounted on the tube of the shock in such a manner that the spring is compressed significantly when the shock is not under load. I think in other words, with the coil-over (fully assembled) laying on the floor of the garage, the spring is already heavily compressed. I've been told this can make the handling pretty bouncy (as if the spring rates are too high [read:stiff]). No experience personally with this setup.

I think there's a narrow band of ideal spring rates that match a truck's specific corner weights... however, it also depends on what the end use of the truck is, as well. A family hauler will want softer springs and a dune jumper will need firmer springs.

And then the shocks should be valved to match the selected springs.

If your truck used to have air suspension the rear bumpstops may be too long for your new setup. Atleast, this happened to me anyway. I didn't see the problem talked about much so I guess it was kind of obvious to everyone (but me, lol)... And basically my truck was bashing the bumpstops constantly. Nice to put in a $3000 suspension system and give myself a chiropractic adjustment before figuring that one out.

Note that this is all off the top of my head, from things I read years ago, and hopefully helps bring some understanding to where the problem may be. And is in no way intended to be a comprehensive guide to suspension... stuff.

great write up!

so it only makes me perplexed to the situation.
front/rear shocks OME 883 fronts for leveling with lean spacer
895e ( springs 2 years) shocks less than 5 months
-new endlinks
-new bushings
-new wheel bearing
-new lower control arms
( stock upper control arms)
heavy ass k02 275/65/18 tires

I felt bumps but i dont recall flying out of my seat and having this springy effect, this odd road dip bounce.

the bounce effect: super stiff up and down, like a truck driver would, imagine just bouncing your self up and down in a seat, very tight spring like bounce.

the last piece is after my alignment did it make the car feel loose and spring like , not before the alignment- so something with caster/camber or whatever , the wheels have been moved forward to some clearing, could that throw off steering geometry?

also is this a pre-load issue, were things not properly tightened on control arms all around?

also car just feels bumpier over all, regardless of PSI ,

i see no oil leaks on the new shocks nothing

 

[Brian3676]

Try a different alignment shop. One that specializes in alignments, not just some Firestone lifetime thing.

Alignment is a HUGE key in how the truck will ride with new suspension

 

[Keros]

great write up!

so it only makes me perplexed to the situation.
front/rear shocks OME 883 fronts for leveling with lean spacer
895e ( springs 2 years) shocks less than 5 months
-new endlinks
-new bushings
-new wheel bearing
-new lower control arms
( stock upper control arms)
heavy ass k02 275/65/18 tires

Holy guacamole, your rear springs are 44% heavier than stock, referencing this thread:

http://www.toyota-4runner.org/4th-gen-t4rs/162125-coil-rates-oem-4runner-oem-fj-moog-others.html

The front OME 883 springs are around 1.2" longer than stock, and only a tad heavier. That sounds pretty similar to the height change I did and the truck could still attain factory alignment without a new UCA. Speaking of alignment:

Try a different alignment shop. One that specializes in alignments, not just some Firestone lifetime thing.

Alignment is a HUGE key in how the truck will ride with new suspension

Agreed... looking over the image of his alignment specs, it does seem pretty close to spec (assuming the specs on the left column are true).

I felt bumps but i dont recall flying out of my seat and having this springy effect, this odd road dip bounce.

the bounce effect: super stiff up and down, like a truck driver would, imagine just bouncing your self up and down in a seat, very tight spring like bounce.

I'm really thinking your rear springs are too stiff. Do you have a full-size k02 275/65/18 spare slung under the truck? Rear plate bumper, fridge, drawers, etc, that weighs down the back? If you keep my mother-in-law back there, 44% is NOT enough extra spring rate for that

also is this a pre-load issue, were things not properly tightened on control arms all around?

Pre-loading, as I understand, is a coil-over assembly method. The only thing I think could get messed up when installing the control arms is if the bolts are fully torqued too soon, locking the bushings in a non-neutral position which would lead to them wearing out faster. The same situation must be observed when mounting the coil-over... put the truck on the floor to tighten the bottom bolt so that the bushing sits in a neutral position at normal ride height.

EDIT: Assuming Toytec has an accurate image of an OME90021, it doesn't appear to have any adjustment in the spring perch height. So only a REALLY long spring could be installed on it in a "pre-load" configuration. Which isn't the case, as that the OME 883 is only a tad longer than stock.

Other than that, the suspension moreless goes together only one way.

I lost my mind, 4 months ago got new ome shocks 900021 and 60004 , now im bumping and flying all over the road-

Glossing over the shocks on Toytec's website and everything seems ok for your setup (assuming you're running stock weight) on the front (OME900021).

However, the OME 60004 rear shocks are valved to match the 895e/895 springs... so they're gonna be stiff as heck.

If it were me, I would choose different rear suspension for on-road comfort. The OME stuff is awesome for off-road, especially for guys with plate bumpers and lots of gear, and you don't need to spend a lot to get it.

Keeping in mind I speak only from looking over the specifications of the info provided. An offroad shop that actually knows how to build things, or a tuning shop that knows suspension, would be able to give solid input. Throwing it on the alignment rack at a place that specializes in alignments may get the specs better... but I don't think it'll effect all the road dip bounce and truck driver up/down stuff very much.

Hope that helps.

 

[sebastian]

Holy guacamole, your rear springs are 44% heavier than stock, referencing this thread:

http://www.toyota-4runner.org/4th-gen-t4rs/162125-coil-rates-oem-4runner-oem-fj-moog-others.html

The front OME 883 springs are around 1.2" longer than stock, and only a tad heavier. That sounds pretty similar to the height change I did and the truck could still attain factory alignment without a new UCA. Speaking of alignment:



Agreed... looking over the image of his alignment specs, it does seem pretty close to spec (assuming the specs on the left column are true).



I'm really thinking your rear springs are too stiff. Do you have a full-size k02 275/65/18 spare slung under the truck? Rear plate bumper, fridge, drawers, etc, that weighs down the back? If you keep my mother-in-law back there, 44% is NOT enough extra spring rate for that




Pre-loading, as I understand, is a coil-over assembly method. The only thing I think could get messed up when installing the control arms is if the bolts are fully torqued too soon, locking the bushings in a non-neutral position which would lead to them wearing out faster. The same situation must be observed when mounting the coil-over... put the truck on the floor to tighten the bottom bolt so that the bushing sits in a neutral position at normal ride height.

EDIT: Assuming Toytec has an accurate image of an OME90021, it doesn't appear to have any adjustment in the spring perch height. So only a REALLY long spring could be installed on it in a "pre-load" configuration. Which isn't the case, as that the OME 883 is only a tad longer than stock.

Other than that, the suspension moreless goes together only one way.



Glossing over the shocks on Toytec's website and everything seems ok for your setup (assuming you're running stock weight) on the front (OME900021).

However, the OME 60004 rear shocks are valved to match the 895e/895 springs... so they're gonna be stiff as heck.

If it were me, I would choose different rear suspension for on-road comfort. The OME stuff is awesome for off-road, especially for guys with plate bumpers and lots of gear, and you don't need to spend a lot to get it.

Keeping in mind I speak only from looking over the specifications of the info provided. An offroad shop that actually knows how to build things, or a tuning shop that knows suspension, would be able to give solid input. Throwing it on the alignment rack at a place that specializes in alignments may get the specs better... but I don't think it'll effect all the road dip bounce and truck driver up/down stuff very much.

Hope that helps.

thank you, this is helpful- back is a rough drop sometime yes, i agree, i have stock bumpers btw.

regarding my specs, now im wondering if there is a golden ratio for certain alignments like i saw people saying camber should match left and right? is that true?

car pulled right but was tight down the road and on bumps, now after this alignment the car tracks like a boss, steering is looser sure but it goes ape shit over bumps, rear end wants to fly out a little when cornering over a bump as well- so something got wacky!

 

[Rodtheviking]

It sounds like your suspension arms, upper and lower were torqued while unloaded. I would have the shop that did the alignment loosen and re-torque with the wheels on the ground. I did this to my upper and lowers after the alignment was done on mine to be certain and my rig rides great.