I have seen several threads related to 3rd gen T4R's harsh suspension and the last one I saw mentioned something about using coilovers on the front suspension and OME coil springs on the rear. It was the "best option" to fix or improve a runner suspension.

Don't know if the wheels I put are causing the bumpy ride as I can't recall my runner to be that rough when it had the original 16" wheels. The suspension performance started to get worst couple of years after putting my 18" TRD/BBS wheels.

I recently replaced springs (OEM ones) and have already replaced my shocks for the 3rd time (2 sets of KYB thinking the first set was already worn out and then got Tokico's looking for something softer) and no improvement at all. The thing is that my ride feels like running on 4 basketballs, I feel the tires bouncing like there are no shocks and just feel the rear differential and front lower arms hitting the rubber bumps/stops. I notice that the suspension clearance is very limited in the runners. Mine is a 1999 2WD Limited T4R.

Looking to get a final and best option to ride my runner on-road without the suspension roughness. Don't do off road so lifting it couple of inches is not what I'm looking for. Getting 1" higher could be an option if it is required to get some comfort.

What do you guys suggest? I've read that good coilovers are expensive but if they do the job, then I'll go for them. Same thing for OME's.

Please advice.

interesting. whats you tire psi at?
new coils/springs with new shocks should ride like the day it was built

It seems odd that it would still be riding that harsh after getting new coils, unless you got coils for the 4wd accidently. I have been plagued with harsh ride issues too since i got my truck. I have KYB gas shocks right now and I thing they are just really stif. But you should post some pictures of your truck showing the tire clearance. If the coils are correct and fairly new you shouldnt be bottoming out at all.

32psig as specified for the original tires and wheels though I remember that when I installed the new 18" BBS rims, it was still acceptable. Don't know what happened...

I know you already got a good bit of information in the original post, but do you think you could give us some more?

replaced springs on all 4 corners with brand new OEM ones?
did you do the work yourself?
shocks on all 4 corners? brand new?
(pictures could be handy to diagnose your problem-mainly a side shot and one showing the bumpstop clearance, but as many as you could take of the suspension might help--If you just want suggestions on good parts to buy I guess the pics are unneccessary-but I think you should be riding pretty smooth so I don't know if you should just throw money at it)

edit: here is what I recently did to overhaul my suspension. I'm very happy with my results, and still quite intrigued by your problem--Bilstein HD Order HELP!!!

I had the same KYB shocks you have, then changed to Tokico. KYB's are stiffer but provides better handling; Tokico's are softer and you'll lose some of that handling. Now it feels like swagging. Been thinking on going back to KYB's in order to gain that stiffness and handling and then getting maybe 1" lift to provide more clearance and avoid frequent contact between the differential and front A-arms and the chassis hit. Feels like running a dropped car but like when you cut the coils. Will measure the clearance between the stops and both the differential and A-arms and let you know the outcome.

replaced springs on all 4 corners with brand new OEM ones? (YES)
did you do the work yourself? (YES)
shocks on all 4 corners? brand new? (YES)

Will get pictures and measurements by tomorrow. Maybe it's cause of the bigger wheels but I didn't recall it to be that harsh at the beginning.

Saw you thread. Getting Billsteins will not be a problem but having another set of shocks resting in my garage hehehe. The thing is to solve the clearance issue. I also noticed you have 16" wheels, not the OEM ones but very close to the original specs. That's something that should make a difference...

These are the wheels my T4R has. I will take a picture from the side so you can compare front and rear height.

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I have 17's, and some somewhat meaty all terrains but there an alloy and not all that heavy(wheels that is). I really don't think your unsprung weight would be to much different then mine.

What are the specs on your wheel/tire combo?

Also, Billstein are typically regarded as being a stiffer shock. I almost suggested you get Billies in my first post, but decided to hold out sense it seemed you wanted a little smoother stock ish ride. (I love how my billies ride and wouldn't really call them stiff but most do-I like them better then monroes and tockicos) For your problem I would typically suggest them right away, but since you just got new springs/shocks I was thinking maybe you had some other problem. I'm still unsure, in fact.

Is that a current picture? It looks like your riding maybe just a little low(may not be low at all) but it doesn't seem like you should be bottoming out.

Wheels are 18" x 9", 10mm offset, each one weighs 35 lbs. They're wrapped in Michellin's P275/55R18. And yes, it is a recent picture. Coils don't even have a year running in my runner.

you got me stumped I guess. I'll definately check back though if you get pics of the suspension. I guess my parting words would be try some new shocks(I like Billsteins). I'm kind of suprised no one else has spoken up yet, hopefully some one more knowledgable then me will soon.

(I see you've been a member since '06, sure hope this community can help out one of their long term members)

You went from a 16" wheel to an 18" wheel, while retaining roughly the same outer diameter of the tire, meaning you lost about 2" of sidewall, as you gained 2" of wheel. That right there is likley why the ride feels harsher than before, you have way less sidewall to soak up the imperfections in the road.

What load range are your tires? If you went up a load range that could also be the issue. I run load D (8 ply) on the runner and its a little rougher than stock but not bad at all and I just put on some 33" E load (10 ply) range tires on my me and wifes expedition. They are set at 50psi and the ride is a little rough.

You are right and could be part of the problem but I didn't recall noticing that type of behavior in the suspension just immediately after changing to the 18" wheels. I will reduce the tire pressure, that should help but surely will result in less MPG and less tire life.

When taking the pictures, I noticed that it has lost some lift on the rear, I remember seeing it dropped in the front. Those 4 coils are OEM's and are not even a year old!

Regarding clearances, see them for yourselves. Barely an inch on the front, just between the A arm stop and the chassis. On the rear, 5/8" or .0625", not even an inch. That's the reason of the hammering I feel on the rear suspension; the differential is bouncing all the time!

Was planning to at least install spacers on the rear to get more clearance and then see what can I do on the front.

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