AccuTune Suspension Tech: Spring Preload

Spring preload is a hotly debated subject when it comes to Tacoma, 4Runners and other IFS vehicles.

Here is the complete article about it: http://accutuneoffroad.com/articles/spring-preload-matters/

Some Tacoma/4Runner specific things:
2" of more of preload is ok in the front, and I would run the lightest spring that'll get you the lift height you want without going solid.

600-700 lb/in springs on Tacomas are usually plenty stiff (or too stiff), and bottoming out or uncontrolled bouncing is usually a result of shock valving not spring rate.

 

Just the subject that's been on my mind. I'm currently playing around with the preload on my ADS coilovers with 14" 650lb/in Eibach springs to get my preferred ride height.
My question is, if I have 2" or more of preload on the spring, is it reasonable to go to a 1" longer spring instead and keep the preload down? This is assuming the spring won't reach coil bind under full compression.

 

Go with a heavier spring rate. Same length spring.

 

The length of the spring doesn't change preload, it just moves the nut up the body. The only time spring length matters is if you can't add more preload without going coil bind (you need a longer spring) or if you run out of threads (could be a longer or shorter spring).

If your spring isn't close to coil bind I would just keep adding preload. If you are close to running the spring solid, then you need a heavier spring.

 

I haven't gotten close to max preload, or coil bind with these springs, they just need more adjustment. I'm hoping the spring rate is adequate.

Good call, I will keep messing with preload to get it where I want it.

 

Hey, I'm bumping this because there is still a lot of misinformation out there about preload, and hopefully we can help you all get a better ride.

Preload is your friend, preload is soft and cushy.
Heavy springs are stiff and firm, heavy springs don't have any preload.

If you want a nice ride, you want preload front and rear.

In the front, crank that nut down and get your lift. 2" of preload is ok.

In the rear, don't buy stiff overland packs if you're not carrying the gear.
The shocks should be your travel limit, not the springs.

Happy to answer questions!!

 

umm..something to think about here, @*TRD* I was going to get the ome extra leaf for the extra weight too

 

Need to bump this thread to the top, maybe some people will read it instead of giving wrong information.

 

Great information here and something I am learning about since I lifted my 2nd gen Tacoma. I got the Boss 2.0 coilovers and Dakar pack because I was due for shocks and a new rear leaf pack. I want a 2" lift in the front but the driver side lean is much more noticeable now. With 600 lb springs, would you guys think 1/2"-2/3" more driver side preload (compared to the passenger side coilover) is ok? Should I shoot for the same preload and just live with the lean? I don't do any serious off roading. Primarily used to get to trails and campsites with 2 bikes in the back.

 

Your fine to preload the driver side more to level it out. It won’t change the ride, there’s more weight over there anyways so that’s why you need more preload to be level.

 

That's what seems to be the consensus from searching this forum. It felt weird to essentially double the preload on the left but that's just in my head. Thanks for clarifying. Looking forward to getting it aligned tomorrow.