Newbie here needs help picking rear springs

Hello All,

New to the forum as we just purchased a used 2016 4Runner SR5. It has just over 156,000 miles on the clock and had very worn-out shocks/struts. We live in NH but flew down to FL to pick up a one owner 4Runner with no rust.

The first thing I did when getting it home was to replace the shocks/struts. I was stunned at how easy this thing is to work on!

Now it is suffering from the rear sag issue which is not surprising because the old rear springs are still in place.

My goal is to be as close to stock as possible for suspension, so I went with the following struts and shocks:


Front
KYB 4528 Strut-Plus
KYB 4529 Strut-Plus

Rear
KYB 349185


My questions are:

1.) How long does it take for the new front strut springs to “settle in” so that I know my front is at its new height? Do they even settle in at all?

2.) How do I select the correct springs for the rear to get me close to a “stock” look?

3.) Are these new front KYB struts now at “factory” height, or too high?


This will be my daughter’s daily driver with little offroad use or towing or even payload. Snow will be where the fun begins when she needs to get to work on time. (She is an EMT)

I’ve read several threads on the sag issue so far, but they tend to be focused on off road, lifting, heavy payload, etc. that we may do down the road, but right now I’m keeping it simple. I’ve also read enough to know that these rear springs are a compromise and there don’t seem to be one-size-fits-all solutions. i.e. - If you have a stock height with no payload, you will sag with substantial weight in the back. If you are OK with some rake, you’ll be level with load.

To sum it up:

1.) Preference is for a “Standard” stance when unloaded or loaded lightly, a little rake is OK if that is the compromise for a certain spring.
2.) Typical payload will probably be 0-100 lbs in the back.
3.) Typically just the driver, no passengers.
4.) Prefer for the ride to be not too stiff, but sporty is good.

With only 40 or so miles on the new fronts, I used a laser level to check the difference between the fender opening heights. After compensating for the pitch of the garage floor to make sure I was on target, the rear wheel well lip measures 5/8” lower than the front wheel well lip.

Does anyone know what the lip height difference would be when a 4Runner “looks level”? I’m thinking that the rear lip height would be above the front lip height and not the same. If they were the same, I suspect that it would still look like it had a saggy rear end.

Or is the correct method of measurement done by measuring from the wheel hub center to the fender lip…..and is there any height data for that? Mine are the following:

Front: 21.5”
Rear: 20.75”

If stock Toyota springs would match the KYB fronts, that’s fine. But there seems to be so many options/brands/models, how do I pick the right one? Dobinsons seem popular with many offerings and a fair price of about $300.

Also, let me know if there are any factors I am missing and need to consider.

Thanks in advance.

 

Just saw another thread about rear springs that was helpful. Didn't see that before. There is a statement from CrikeyMike that says "The baseline we use is 20" front and 22" rear". I also found that on a Dobinsons reseller site after looking more into their springs.

So, looks like a 2" difference from front to back is the norm.

In which case, if the front doesn't settle in would require a 23.5" height on the back?

Again, CrikeyMike says that a "C59-599 Dobinsons coils tend to sit at 23.5" from hub to fender with no rear weight and no 3rd row seat."

So it would appear a set of C59-599 Dobinsons would be my solution if the front stays at this height?

If so, I don't think the KYB Rear shocks will be compatible......

 

Welcome to the forum.

Those strut assemblies you bought appear to be stock height according to the internet (no mention of a lift), so they haven't settled yet. 500-1000 miles to break in. Your rear is 1" low at least, compared to new, which is pretty unusual for a 5th gen to sit that low.

I suggest breaking in the suspension for it to settle, it should come down to 20-20.5" (but I have no experience with KYB). Those rear shocks are most likely also only for stock height, so C59-323 rear coils would be the closest option to that.
https://exitoffroad.com/product/dob...l-springs-for-lexus-gx460-and-toyota-4runner/

 

Thanks for the welcome. And a fast response!

Yes, it is my understanding that the struts are stock height. I had a chat with KYB since writing to you and their tech team will also get back soon regarding the KYB specs.

I will run it for the miles you indicate and allow a break in, and then re-measure. Looks like the rear springs need a change anyway so worst case is I need to also get different shocks to accommodate the extra height. But on the bright side, I guess my daughter gets a bit of "lift" thrown into the deal

Thanks again, and I'll catch up again when I have more data.

 

Welcome

 

those are 220 lb rating. My Eibach T13 rears are 195 lb (13% stiffer than stock) as a comparison.

 

So the Eibach's would be a more comfortable ride. Is the 220 and 195 pound rating referring to the payload capacity in the rear?

Thanks

And I heard back from KYB support and they suggest as a first step I loosen/retighten the strut bolts while the vehicle is on the ground. Not sure about that, but I'll give it a shot.

From KYB:

Hello,

Sorry to hear about the height difference on your 4runner. Our fitcheck results in the real world did not show any increase of height to what you are showing. We would recommend what customer support said and loosen the bolts slightly, bounce the front end a couple times and tighten it again while on a leveled surface, there could be a slight increase and that should go away with time, if that is not the case please reach back out to us with updated measurements and we will determine the next steps.
Regards,

Technical Support

KYBAmericas Corporation

 

the 195 is 195 lbs/inch. This means that a force of 195 pounds is required to compress the spring by one inch in theory

Ive put 300 in the rear and it dropped maybe 1/4-1/2” and ive put close to 600 lbs and it dropped a tick over 1/2”. I love my front/rear suspension set up around town or 1100 mile round trip to NC and back to Pa

regarding loosening the lower shock bolt then putting under load them retightening, that is correct. Same with the LCA bolts. They should be under load as well when torquing to spec

this is loaded up with a full tank of gas, vaca gear 1 adult and child in the car. Add me and thats another 240 lbs.

 

Just loosened/re-torqued the strut bolts. Bottom and top 3. Bounced it real good and remeasured. Still 21.5'

I did not loosen the LCA bolts as I just had an alignment done 3 days ago along with brand new tires. I'd hate to screw that up and potentially wear the tires while I'm doing the 500-1000 miles of seating. I could always do that after the miles. Potentially that was already done during the alignment I suppose, to an extent.

I'll report back to KYB in the mean time and see what their response is.

Appreciate the input from you all.

 

Do have any pics of the front struts in place top and bottom where the coil sits? Maybe we can see something is off

 

I’ll get some pics tomorrow out on the
sunlight.

I like the way your rig sets. That’s what I’m looking for but will probably be a wee bit higher overall if these struts are stubborn.

 

sounds good

thank you! I have a 2” lift Bilstein 6112 w/600 lb coils front, 1.5” lift Eibach T13 coils rear, Bilstein 5100 rear shocks, 285/70/17 Falken WP AT3, Energy Suspension front bumpstops, SSO Slimline Bumper and Durobumps 4.25” rear bump stops

just measured mine, but from ground up to the wheel well lip. 36.5” front and 37.75” rear with a full tank of gas and 50-75 lbs of constant weight/gear in the back cooler.

 

Took a while to post these. Been trying to use my late summer Saturdays wisely......smoking ribs, swimming and having a few cold ones

Uploading some photos of the struts, but they're not that informative, at least from what I can see.

I have checked to be sure the spring ends are in the correct locations of the bottom plates and they look fine.

 

Hate to say it but that's worse than a 3rd Gen rear spring sag...can you post up some pics of the rear suspension?

 

that front is not stock replacement height coil/strut set up. Looks like they gave you lift springs. Can you see if there’s a part number on the coil? This is what my 2022 look like new (under 300 miles) with stock front suspension and factory 265/70/17 before I did the lift and bigger tires.


you have much more of a gap from top of tire to wheel well lip

 

The rear ride height is perfectly stock, maybe a bit higher than stock. You can see it because of the trailing arm angle. That angle is right where it’s supposed to be for a stock setup, just a little bit more angle than parallel to the frame. In fact, most stock SR5s I’ve seem have trailing arms completely parallel to the frame.


The only reason the rear looks too low, is because the front is way too high. I agree with the OPs concerns, the new coils made the front ride height way too high.

 

markings should be somewhere on one of the coil windings possible

 

as soon as the vehicle and I are in the same place again, I’ll check this out.

meanwhile, KYB support has asked that I measure the fender lip heights from the ground up. They at least seem genuine in their support efforts.

 

So just thinking ahead while I wait.

If for some reason KYB has no answer, what will I do?

a.) I could size replacement springs and shocks for the rear to compensate. But then I’d essentially have a “lift” instead of stock. There is no real need for this so it would just be for looks. Would probably cost an additional $500 and labor. Maybe a bit more as I haven’t investigated too much yet. Just guessing at $300 for springs and at least $100 for each shock for ones that can handle the lift.

b.) Replace the front KYB with another brand/Model of quick strut that would give me “stock” heights. Then see if the back still needs new parts. I’d probably prefer the stock height.

pros and cons and ideas? Chime in.

 

it’s just my opinion, but I would have KYB send you a complete new strut coil spring assembly that is factory height. They clearly sent you the wrong one because your front end is definitely lifted with what they sent you

 

So that would be the best solution. But I find it hard to believe they would have put the wrong spring on these Quickstruts. (but I can be naïve at times )

It will be interesting to see what they figure out once I get the measurements that they have requested.

 

Appreciate the ruler indicator, I wasn't sure if I was seeing that arm correctly and only judged by the near rectangular 'light' shadow between it and the undercarriage...made me think it was parallel and I know these arms generally tilt downward a bit. Don't know what happened with my earlier post (seems I get one here and there when typed on my phone that is missing a chunk), was supposed to infer that it "...looks worse than...". OP' front end looks similar to my 2" lift setup.

 

well I believe they did because I sent you a picture of my stock 2022 trail special edition when it was brand new and yours is significantly higher

here’s what it looks like lifted. Which is in more in line with what you have going on right now

 

Maybe I missed it... but is your T4R a rear wheel drive only or 4 wheel drive?

If it's rear wheel drive only, might you have gotten suspension parts for a 4wd?

There are different KYB suspension setups for rear wheel drive only vs 4wd. If you put 4wd front coil overs on a 2wd Florida truck, the front end might end up too tall.

 

That’s a fair question!

It’s a 4wd. Just added that to my info.

thanks

 

I measured the requested heights last night from the ground up.

Front was 36-5/8"
rear was 35-7/8"

I sent that to KYB and am awaiting their next reply.

 

yep your front is lifted for sure. Thats my height measurement on my 2” Bilstein lift in the front

 

Thanks for the comparison. Much appreciated.

So I just heard back from KYB. Here is what they had for a response:

Yes, the front does seem to be a little higher than normal. We believe there are two reasons for this. First, the coil spring is still in its break-in period and should settle some in due time. Second, the ride height seems to be an inch lower than normal. This is likely due to the age and mileage of the truck. Having the rear sitting low will lift the nose off the truck.

We would recommend giving the new front coil springs time but, more importantly, mileage to settle. You should also look into replacing the rear coil springs.

Regards,

Technical Support


I find it hard to believe these will settle by 2 inches in time. Probably have one or two hundred on them when I measured them last night, and zero settling.

I have until Aug 30 to return them (Amazon). So, looking at my options.

If I decide to keep these, then I'll have the lift. To be honest, TrailSpecial22's sits pretty damn nice. I will then need to buy new rear springs which probably need a change one way or another anyway, and a set of shocks that will allow a rear lift.

But, If I decide to keep the lift, then should I go with another brand of front strut? Is there something better for nearly the same $360? This I would do just out of spite because I'd be annoyed at KYB. Just the way I'm wired.

Or...can I purchase a different front quick strut that will give me factory height but is not a piece of junk? I haven't been able to find anything so far.

this was meant to just be a simple strut swap

 

I don’t buy their explanation, even brand new like in the picture I showed you, my 2022 was not as high as yours.

i’ll let others weigh in on this