Suspension upgrades for better handling. Advice, comments?

[52577]

Hello all,

First and foremost, thanks in advance for helping out on this. Let me first tell you the specs of my rig:

2004 SR5 Base V8 RWD
32K original, 1 owner miles. condition is like new.
Tires: 4 Michelin LTX MS2, P265/70 R 16 – 3.5 years old with majority of tread left.
Suspension: 100% Stock
Usage: Daily driver and some longer road trips. No rock crawling, no heavy off-roading use, no lift. Seasonal driving conditions include 2 months of occasional, light snow including mostly rain 6 months, and clear weather 6 months.

Suspension improvements:
That all said, I’ve had my 4Runner for a month now. I love it. The ride quality is very compliant and soft. However, it leans quite a bit in turns and has considerable, and annoying understeer. True, a sofa on wheels isn't going to handle like a Porsche, but I'd like to improve upon it. The rear tends to hop a bit over washboard roads and it also feels as though it might be leaning a bit to the right when driving on flat surface.

I understand this is normal for the stock 4Runner suspension. My guess is probably Toyota designed it with more understeer as it's safer. For these reasons I have less confidence of avoiding a collision if I had to turn suddenly and sharply. Even more so in inclement weather.

My hope and goal is to stiffen up the suspension, even it out the understeer, so it corners as flat as possible for handling quality and safety without sacrificing all comfort.

Some research I came up with includes:
1) 4 new shocks (Bilstein 5100’s or 4600's)
2) Different springs
3) Beefier anti-sway bars
4) New poly sway bar bushings.
5) Quality AT tires (BFGoodrich KO2 or Goodyear Wrangler DuraTrac)

Shocks:
I installed the Bilstein 4600’s on my last rig and immediately noticed an improvement in cornering, braking and controlled ride. I was so impressed by them that I now tell everyone. They will be a definite upgrade. Any comments or info I should know about the B-5100’s and the 4R?

Springs:
Are different springs necessary for better handling? If so, what springs do you recommend? I want to keep height stock, and preserve as much ride comfort as possible.

Anti-sway bars:
I read a few comments online that thicker sway bars in the rear decrease traction in the rear wheels. Being stiffer the vehicle becomes flat in the turn, not allowing any weight shift. This will cause more oversteer. Knowing that in stock form the 4Runner tends to understeer, my guess is, a stiffer rear sway bar should compensate and even out? ... Thoughts?

What anti-sway bar brand do you recommend? I found the thicker, Addco brand rear anti-sway bar online, but was unable to find the front. Do they make one and if so where can they be purchased as a set? Do you recommend making this modification?

Would I need to upgrade to stronger end links or will the stock end links be strong enough with a thicker sway bar? If upgrade is necessary what brand is best?

Poly sway bar bushings:
Is this necessary in my case since everything is tight and new with the low millage? Not sure if stock bushings would fit a thicker sway bar. It seems like most people are using the Energy Suspension sway bar bushings. Do you recommend this and if so what brand do you recommend?

Tires:
Again, this may be overkill and perhaps unnecessary in my case since my tires are almost new? If my understanding is correct the Duratrak or KO’s have stiffer sidewalls and perform well in rain and snow?

Well, that’s about all for now. I hope to get this done before the harsh winter weather sets in.

Thanks again and I appreciate the comments and help.

 

[VT245]

I have a 2008 V8 SR5 4WD that I added the bilstein 5100s to (fronts at 0.85), and C-rated 265/70 KO2s (stock springs still). I immediately noticed better handling with the 5100s as most people have reported. While its not sports car, it certainly leans less in the corners and does much less brake diving. Im unsure how much of a difference the KO2s made on top of this, but I like the overall setup quite a lot. Also this suspension/tire setup yielded much less rear end sag when I have my trailer attached. I did upgrade my sway bar bushings, but that was because I had the infamous front end "clunk". I used the following bushings on my front sway bar and it solved my clunk, but again unclear on the handling improvement if any.

https://www.amazon.com/gp/product/B003879X7I/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

 

[Morphyne]

Here are my takes:

Replacing 13 year old shocks should Def improve ride.
New springs should as well. You can order new factory height springs from Moog.
New tires would also help. Your current tires sre a soft wall design. They are intended to improve ride quality by reducing sidewall stiffness. New E rated ATs will improve cornering and body roll at the expense of that cushy, supple ride. C rated will be one step further. However the additional rotating mass may hurt gas mileage.
As far as bushings are concerned. I would do these last. Mainly because they are such a pain in the as to do. But I would inspect all of them for signs of wear and cracking.
So check you sway bar links on the front and back. Those may need rebuilding or replacing.
Do not get poly bushings. People who have generally end up regretting them because they sqeak pretty badly
I would save the roll bar for last. That is the least likely place to upgrade

 

[52577]

Here are my takes ...

Thanks. I'm confident the B-5100 will improve handling. As mentioned, I had them before on my previous SUV and they are amazing.

With only 32K miles on the odometer, and flat road driving would shocks be worn out already? Is wear based on time or use?

Yes, I've heard the same thing about the poly bushings squeaking like mad. For that reason I'm reluctant to switch.

As mentioned above, the 4Runner has considerable and annoying understeer. Would a thicker, rear sway bar (producing oversteer) compensate and correct the understeer?

I had a throuough pre-purchase inspection at Toyota and it came back flawless. I inspected the undercarriage before purchase and it's like new under there. It was garage kept under car cover for it's 15 years when not in use. Seriously, all the stickers and such look as if they've never been touched. I can check again but I doubt there is anything loose or broken under there. zero squeaks or rattles.

 

[Morphyne]

Thanks. I'm confident the B-5100 will improve handling. As mentioned, I had them before on my previous SUV and they are amazing.

With only 32K miles on the odometer, and flat road driving would shocks be worn out already? Is wear based on time or use?

Yes, I've heard the same thing about the poly bushings squeaking like mad. For that reason I'm reluctant to switch.

As mentioned above, the 4Runner has considerable and annoying understeer. Would a thicker, rear sway bar (producing oversteer) compensate and correct the understeer?

I had a throuough pre-purchase inspection at Toyota and it came back flawless. I inspected the undercarriage before purchase and it's like new under there. It was garage kept under car cover for it's 15 years when not in use. Seriously, all the stickers and such look as if they've never been touched. I can check again but I doubt there is anything loose or broken under there. zero squeaks or rattles.

Im basing this on age. you have an amazingly underutilized 4runner. it could be that it drives just fine and it is just a big ole fat lady on the turns. i have no experiecne with sway bar mods. all i can say is that i changes out my springs to a stiffer set of new Moog fj cruiser springs. i also added Goodyear Silent Armor AT tires and 5100s and the body roll is pretty minimal for my tastes.

 

[52577]

Im basing this on age. you have an amazingly underutilized 4runner. it could be that it drives just fine and it is just a big ole fat lady on the turns. i have no experiecne with sway bar mods. all i can say is that i changes out my springs to a stiffer set of new Moog fj cruiser springs. i also added Goodyear Silent Armor AT tires and 5100s and the body roll is pretty minimal for my tastes.

Ha! Ha! I laughed when I read that. You are so correct. It's like a land yacht, a sofa on wheels in the turns. No there isn't anything wrong with it, it's just the way it handles. But hopefully I can improve upon it.

I'm reluctant to change springs as height will increase and I don't want any unnecessary wear on the components. I read that up to 3" lift is safe, but still don't want to risk it.

This thread compares all the springs, height, rate, etc., although 2WD isn't listed -->> http://www.toyota-4runner.org/4th-gen-t4rs/162125-coil-rates-oem-4runner-oem-fj-moog-others.html

If you're interested, this video is a good explanation of how stabilizer bars work and don't work. I'm still learning myself -->. https://youtu.be/WhWZ57baTOw

B-5100's and stiffer sidewall tires seem like a good option to start.

 

[Whammy]

32K mi?? Wow!

 

[fordracing19]

Lol. I have no handling complaints with adjustable Icons on all 4 corners and no sway bars front or back on 33's.

 

[52577]

32K mi?? Wow!

Well ... I put a few miles on it.

 

[52577]

Lol. I have no handling complaints with adjustable Icons on all 4 corners and no sway bars front or back on 33's.

How is that setup when cornering fast regarding body lean or understeer/ oversteer?

 

[Whammy]

Well ... I put a few miles on it.

View attachment 274721

Should have waited three miles to take that picture #allaboutbinary #2^15

 

[4Rnr4Evr]

Swaybar bushings make a serious difference in cornering. To me they are super easy to swap and absolutely worth it. Stock bushings have so much give that the swaybar just can't do its job.

 

[ukbloke]

2004 SR5 Base V8 RWD

It's refreshing to have a suspension thread that's not about the lift!

I've had my SR5 V8 since 2004. I don't recall ever encountering significant understeer and I don't drive it like an old lady either. Sure, there's body roll and general floatiness, but how hard to you have to drive it to find understeer? But I think I figured out maybe why your experience is different - you have RWD, mine is all-the-time 4WD.

You might want to try FJ springs to get a little extra stiffness without a huge amount of height.

 

[theoutbackdream]

Suspension improvements:
That all said, I’ve had my 4Runner for a month now. I love it. The ride quality is very compliant and soft. However, it leans quite a bit in turns and has considerable, and annoying understeer. True, a sofa on wheels isn't going to handle like a Porsche, but I'd like to improve upon it. The rear tends to hop a bit over washboard roads and it also feels as though it might be leaning a bit to the right when driving on flat surface.

I understand this is normal for the stock 4Runner suspension. My guess is probably Toyota designed it with more understeer as it's safer. For these reasons I have less confidence of avoiding a collision if I had to turn suddenly and sharply. Even more so in inclement weather.

My hope and goal is to stiffen up the suspension, even it out the understeer, so it corners as flat as possible for handling quality and safety without sacrificing all comfort.

Some research I came up with includes:
1) 4 new shocks (Bilstein 5100’s)
2) Different springs
3) Beefier anti-sway bars
4) New poly sway bar bushings.
5) Quality AT tires (BFGoodrich KO2 or Goodyear Wrangler DuraTrac)

Shocks:
I installed the B-5100’s on my last rig and immediately noticed an improvement in cornering, braking and controlled ride. I was so impressed by them that I now tell everyone. They will be a definite upgrade. Any comments or info I should know about the B-5100’s and the 4R?

I have B-5100's on my T4R and upgraded the springs at the same time. I love my B5100's since they were cheap, and are good enough for what i'm doing. I just can't justify spending the money on Icons when I don't go wheeling every day. Some board members might oppose it, but I say go for it!

Springs:
Are different springs necessary for better handling? If so, what springs do you recommend? I want to keep height stock, and preserve as much ride comfort as possible.
As with any suspension job, you will need to change one thing at a time and go from there. Stiffer springs(within reason) will handle better, but you're compromising ride comfort. But it depends if you also lug around nothing in your trunk, or a lot of stuff in your truck on a daily basis. I would recommend getting a set of used FJ springs or OEM replacement springs. You may gain a bit of height, but the ride will be similar.

Anti-sway bars:
I read a few comments online that thicker sway bars in the rear decrease traction in the rear wheels. Being stiffer the vehicle becomes flat in the turn, not allowing any weight shift. This will cause more oversteer. Knowing that in stock form the 4Runner tends to understeer, my guess is, a stiffer rear sway bar should compensate and even out? ... Thoughts?


A thicker rear sway bar doesn't decrease traction. You still have the same tires. You're still transferring the same amount of weight in the turn. A stiffer rear sway bar helps keep your frame/body stay flatter. Essentially what it does is make the weight transfer much faster(from inside wheel to outside wheel), thus making you reach the limit of your tires much faster, which induces oversteer. The technical version is that your car has a RCD(roll couple distribution), think Center of mass when neutral. When you increase the size of the rear sway bar, you are moving this RCD towards the rear of the car, causing more weight to transfer to the rear outer tire. If you feel really comfortable with the rear end coming out, especially in inclement weather, go for it. Otherwise keep it stock. However, the sway bars will combat your problems with the car rolling too much, and understeering.



Poly sway bar bushings:
Is this necessary in my case since everything is tight and new with the low millage? Not sure if stock bushings would fit a thicker sway bar. It seems like most people are using the Energy Suspension sway bar bushings. Do you recommend this and if so what brand do you recommend?

Poly sway bar bushings can help, because your car is still quite old, even though it's low mileage, but not necessary. I'd recommend just waiting, until you decide to buy a sway bar or not. Even then, you're probably better off getting something else.

Tires:
Again, this may be overkill and perhaps unnecessary in my case since my tires are almost new? If my understanding is correct the Duratrak or KO’s have stiffer sidewalls and perform well in rain and snow?
I don't have any clue about if stiffer sidewalls perform well in rain and snow, but stiffer sidewalls will deflect less, so you will have a harsher ride, but with better handling characteristics. The taller of a tire you get, the laggier your steering will be. The wider the tire,
the more lateral grip you'll have, with less responsive turn in. The smaller your tire, the more responsive. The narrow the tire, the more responsive it will be on turn in.

My response will be in red.. But also.. 32k???!?@#?!@? I hate you...

What tires do you have currently?

If you have decent/good tires, and your aim is specifically to stiffen up the suspension, neutralize the truck, so it corners as flat as possible for handling quality and safety without sacrificing all comfort. then I think Shocks and springs are a good start. Then decide from there if you still think the roll is so bad, that you want/need sway bars.

Poly sway bar bushings will be minimal. Tires will be important for truck responsiveness, but it doesn't seem like you're worried about that.

 

[gfluff]

I say run FJ or Taco front springs and bils all around. You'll get a little stiffer, sportier feel. Still compliant, still fine for daily driving.
Here's some info from me. I work in a tire shop. We have a big fat speed bump in the lot. Driving 4Rs over the speed bump is pretty different than FJs or Tacos. 4Rs have the softest front springs and lowest front ride height of the 3 trucks. 4Rs feel like crap over the speed bump. They have very little up travel from the factory, and hit the bumpstops easily and quickly. Look at the distance from the bumpstop to the area it contacts...there's little to no room there. Not the same on the other 2 trucks.
I know you're not looking for lift, but I honestly think it's super beneficial to add a little up travel from a touch of height increase from a stiffer spring. I'm talking an inch or less of height, not 2-3inches. The ride will improve. But that's just my 2cents.

 

[BIGWIG711]

I have a 2008 V8 SR5 4WD that I added the bilstein 5100s to (fronts at 0.85), and C-rated 265/70 KO2s (stock springs still). I immediately noticed better handling with the 5100s as most people have reported. While its not sports car, it certainly leans less in the corners and does much less brake diving. Im unsure how much of a difference the KO2s made on top of this, but I like the overall setup quite a lot. Also this suspension/tire setup yielded much less rear end sag when I have my trailer attached. I did upgrade my sway bar bushings, but that was because I had the infamous front end "clunk". I used the following bushings on my front sway bar and it solved my clunk, but again unclear on the handling improvement if any.

https://www.amazon.com/gp/product/B003879X7I/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

I upgraded to K02's just last week and even still on stock suspension, the car handles significantly better.

 

[52577]

What tires do you have currently?

In my original post.

 

[52577]

I upgraded to K02's just last week and even still on stock suspension, the car handles significantly better.

Yeah, I like the look of the KO2's and they were a top choice. Although, I get many months of rain here and from owner reports they're not good in the rain ...

Link:

http://www.toyota-4runner.org/5th-gen-t4rs/246726-ko2-no-traction-scary.html

 

[52577]

This is a highly dramatized video, but where it talks about roll and handling, and wind sway, that is what it is going slightly. So almost certain it's the shocks. Don't worry, I would never get Monroe's. I'm sold on Bilstein's

https://youtu.be/Cro4DoTQCSg

|

 

[chompster4runner]

Yeah, I like the look of the KO2's and they were a top choice. Although, I get many months of rain here and from owner reports they're not good in the rain ...

Link:

http://www.toyota-4runner.org/5th-gen-t4rs/246726-ko2-no-traction-scary.html

I can say with confident that KO2 sucks bad in the rain. Took a trip to Washington beginning of this year and the weather was just horrible. Had to drive in 4wd high just to have some sort of control. Everyone else were flying by me as I struggle to control the truck.