Getting a 4th Gen, Suspension Questions

[m85476585]

I'm buying a 2007 Limited V8 with 78,000 miles on Monday. I can't wait!

I've test driven the car a couple times, and the front shocks are shot. There's lots of brake dive, and it bounces after hitting a bump or hitting the brakes hard. The rear seems OK. The car was owned by an old woman who passed away, so it's a granny car and it's been driven lightly as far as I can tell. But she did live on a dirt road, so daily driving on the dirt road and the extra weight of the V8 probably did it in for the front shocks. The tires are also worn out, and the dealer noted that it needs alignment because of abnormal tire wear. Sounds like a perfect time to change the suspension!

I do mostly highway driving, so I think I want the car to be optimized for that but a little more capable than stock off-road. I'm thinking of starting with a 1.5-2" lift, and I'll see how it goes.

I might go with:
-Blistein 5100 shocks
-Rear Toytec Superflex coils
-Front stock springs on one of the higher Blistein settings, or Toytec/Eibach 112620 springs on one of the lower settings

Alternatively, I could keep the stock rear springs and get 1.5" lift rear spacers. What's the difference between the factory springs and aftermarket (front and rear)?

The V8 is a big chunk of cast iron up front. Will I need more lift to compensate for that, and how much? I don't want to level the truck because my bike rack on the hitch will take care of that. It's 60lbs empty and 150lbs loaded with 3 bikes. I'm looking for the same inches of lift front and rear, not more in front like most setups.

Finally, do I need anything other than the blistein shocks, some springs, and whatever parts are on the car now (top mounts?) to assemble front struts? Obviously a spring compressor will be needed to do the job. The Toytec 3" Blistein 5100 kit costs significantly more than buying the same parts individually, but they say it has "Fully assembled front coil over using Toytec aluminum top mounts and urethane bushings"

 

[txclimber]

I'll address a few of your questions:

The difference between factory springs and aftermarket depends on which aftermarket springs. Some could be the same. Typically, when you decide on aftermarket springs, you're deciding on spring rate, length, and how much weight they're designed for based on your needs.

The difference between a longer spring and a shorter one with a spacer is that the spacer won't flex like a spring does so even though your truck sits higher the travel available to the axle does not change. Sometimes (like in the front especially) spacers will actually reduce the amount of travel available.

You shouldn't need new top hats unless there is something wrong with your stock ones, and you're right they're much cheaper to buy unassembled.

 

[Bossman]

Congratulations on your upcoming new purchase

Before diving into a suspension swap, be sure that you know what you currently have on the vehicle.

Your Limited V8 may be equipped with the X-REAS sport suspension system. Seems unlikely based on your description of how the 4Runner currently drives, but is is a possibility. If you have this system and are replacing it, all four shocks must be swapped out (it is a sealed, cross-linked system).

Your Limited V8 may also be equipped with RAS (Rear Air Suspension) that has height control. There would be switches for this in the centre console between the seats. This RAS takes the place of regular coil springs.

Be sure to check out what you have before proceeding.

Welcome to the forum!

 

[MarkinWMich]

Good advice, so far.

If you are generally looking for more daily driver performance and a mild lift, then you do not have to spend a lot of money to get there. One of the popular options for this generation of 4Runner is swapping out the stock springs (front and rear) for the FJ Cruiser springs. This simple swap offers a mild lift and better handling, primarily due to it's higher spring rate. The higher spring rate will reduce body roll and front end dive.

You do not necessarily need to use a spring compressor when changing your springs on these 4Runners/Tacomas/FJs. There are YouTube videos on how to do this, and it makes things go so much quicker and easier.

You can't go wrong with the Bilsteins, either the HD "stock" versions or the 5100s.

When you get on the web sites like ToyTec, All Pro Off Road, ICON, etc., it's easy to feel like a kid in a candy store. Just remember, "Is it something I need, or something I want?" "Can I install this part alone, or does it mean I have to install these other parts, as well?" "How do I justify this purchase to my wife when she had other plans for that money?" Whenever you are altering the stock suspension geometry that the Toyota engineers have spent a lot of research and development on, there is the potential for bad decision making and bad handling. Think like an engineer and be fiscally responsible.

 

[m85476585]

Good advice, so far.
Whenever you are altering the stock suspension geometry that the Toyota engineers have spent a lot of research and development on, there is the potential for bad decision making and bad handling. Think like an engineer and be fiscally responsible.

I agree. I don't completely understand how suspension works, so I want to error on the side of not screwing it up. I want an off-road capable vehicle, but wheeling becomes an extremely expensive sport taken to the extreme, and I already have enough other outdoor sports I want to spend money on! I want some lift for off-road capability, not for looks, as long as it doesn't compromise other aspects of the handling too much. How the car looks is one of the least important things to me.

I'm coming from a small car, so I want the on-road handling to be as good as it reasonably can be for an SUV. I think it's already good stock (with working shocks), so I don't want to make it worse. I also like a comfortable ride, and I realize there's a trade-off between all these things.

Technically it's not a daily driver because I bike to work and to most errands! So I'll mainly use it on the weekends or after work to go mountain biking, hiking, skiing, camping, etc. But most of that is still on the highway, and the last few miles to trailheads or campsites is usually relatively mild dirt roads. The fact that I drive relatively little makes the higher operating cost (gas, tires, etc) bearable.

It doesn't have RAS because there are no buttons for it inside. I forgot to check if it has XREAS, but I don't think it does. I like the idea of it, but it doesn't sound like it was implemented that well since it's not serviceable.

I need new shocks, alignment, and tires (the ones on there are literally bald in the center). I want to get some lift, so it makes sense to do it now. I also want to get some skid plates, but I'll probably wait until spring for that. Aside from that I'm not planning on spending much money on the car.

Thanks for the help so far! Now to do some more research on springs...

 

[MarkinWMich]

Keep in mind, my previous hobby was road racing and autocross with my modified Mustang. So, switching to an SUV, my first thoughts are with the suspension and handling. SUVs typically have this issue with a relatively high center of gravity, which naturally puts them at a higher risk for roll-overs. Now, if you start lifting it with suspension and/or tires, it becomes more of a safety issue.

Things to consider to help reduce this risk:
1. Higher spring rates...stiffer coils help reduce body roll and nose dive under hard braking.
2. Stiffer side walls on your tires. Consider moving to a C-load or Light Truck tire.
3. Polyurethane bushings on your sway bars and links.
4. Widening the track with wider wheels and/or wheel spacers.

 

[m85476585]

I've decided to just replace the worn OEM shocks with new OEM ones for now. I like the way it rides (I've driven one with good shocks before), and I'm afraid it will be worse if I start changing things. I found a set on ebay for around $300, and I'll try to install them myself since the dealer and an independent shop both want around $400 for the installation alone.

Most of the aftermarket shocks seem to be designed with stiffer damping to handle stiffer springs (though that's just based on subjective reports, I can't find any numbers). I don't want springs that are much stiffer because I don't want to make the ride harsh or lose range of travel off-road, and I don't think stiffer shocks would be good without correspondingly stiffer springs. The stock springs and shocks were designed to work together with the weight of the truck, so I'll stick with that unless I can find something that I'm sure will be better.

I can't find any LT tires in the stock size (265/60r18), or not any I want at least. I don't think I want LT tires anyway since it seems like they tend to be heavier, lower gas mileage, and have a harsher ride.

I'm going to do everything I can to get good gas mileage out of this V8! It's not looking good right now, showing 17.4 around town today. At least I don't drive around town much. If I can consistently get 20 I'll be happy. I have yet to see how much the computer overestimates the mileage compared to filling up at the pump, but hopefully it's not too far off.

Some long-term projects...
With some adjustments the JBL audio system sounds alright. The low and mid bass sounds boomy or muddled to me, but turning down the bass EQ setting one or two clicks helped. I don't mind bass if it's clear, but this didn't really sound good. Turning up the treble setting one or two clicks helped, too, and the stock tweeters are not bad. Now it sounds about as good as the cheap Polk speakers I had in my old car, so improving the system is not urgent. I'm going to measure the frequency response of the JBL amp at each output to see if that can be used to power new speakers, or if I need to look at a new amp for any upgrades. This page Prius JBL Audio system response, specs, and photos suggests that the amp might have a non-flat frequency response. My guess is that it's to correct the response of their speakers or the car as a whole system, but if I start replacing speakers I want a flat, low distortion path from the audio source (my smartphone) to the speakers. I will try to measure distortion (THD), too, but that's more difficult to do without lab equipment unless there is major distortion in the system somewhere. I think I can at least check for excessive distortion.

I think this truck will benefit a lot from sound deadening, and it will be able to handle the extra weight better than my old car. That barely had enough power or payload capacity for what I used if for, and full sound deadening treatment will add at least 100lbs. It will probably decrease MPG slightly, but it's worth it for a quieter ride and better audio. I want to do something a lot like this: http://www.toyota-4runner.org/4th-gen-t4rs/91953-sound-deadening-new-audio-setup.html but with better materials, such as what Sound Deadener Showdown | Your Source for Sound Deadening Products and Information sells. I have yet to decide if I want to commit to doing it all at once (only tearing out the interior once) or do it in stages as time permits.

Some hacks...
I'm planning on making a circuit to override the recirculate button. We have great fresh air most of the time here in Colorado, and I don't want the car to seal in all the stale air. I will put a switch in one of the blank buttons by the center console, then make a circuit that compares the recirc light to my setting and switches it appropriately when the auto system gets a mind of its own. I also want to add an LED that monitors the A/C clutch to see when it's running. I'll use that to see how much it runs when the defroster is on so I know when I'm using more gas than I might need to. It's probably not worth the effort to make an A/C override switch, but it wouldn't be too difficult to do (add a switch that interrupts power to the A/C ("MG CLT") relay).

I'd like to add some hard wired USB ports, maybe inside the center console and/or in the rear like this write-up: http://www.toyota-4runner.org/4th-gen-t4rs/132027-rear-seat-usb-install.html

If you have any suggestions or requests for electrical mods/hacks/DIYs, let me know! I like to keep the stock look when I can, though.