I just had a shop install the 99 springs on my 4runner 2 weeks ago. I am now getting the following measurements from the ground to the center of the wheel well:
front right - 35.50 inches
rear right - 35.50 inches
front left - 35.25 inches
rear left - 35.00 inches

4runner is leaning to the left due to additional weight of gas tank, steering column, battery, etc. The rear left is just too low, and I want to install an OME 10mm trim packer. I think I can install it myself. I don't want to risk injury, though, when I crawl under the truck. So, where do I position the jack stands to safely lift the rear wheel? Do I disconnect the shock to get the spring to drop out? Thanks

 

You'll want to support the frame because you need to be able to drop the axle all the way down. I put my jack under the rear diff, jack it way up, support the frame,remove the wheels for easyier access, disconnect the swaybar end links on both sides, disconnect the bottom shock bolt, carefully lower the rear axle down. Watch your brake line, it'll start getting tight. This should give you enough space to get the springs out. I used a compressor on mine, just so I didnt have to fight with them. If I forgot something someone else will chime in. Good luck!

 

There should be a specific R rear spring and L rear spring. My friend just went through the same swap with his '98 4runner. Are you sure they didn't mix 'em up? Did you buy them new from the dealer or used?

 

Applejack speaks the truth.

Go to Sonoran Steel's website. Check the page on springs. I believe they show a set of '99 springs which have a color code on the springs, which specify left and right springs.

Then check yours, that would be an easy thing to check first.

 

I bought the springs from the dealership new. The front springs differ from each other, but the rear springs are the same. I checked the part numbers, and I checked sonoran steel's website before I took my 4runner to the shop. I then made sure the mechanic knew where each springs went. He installed them correctly. OME trim packers have been ordered. I'll probably just put one 10mm spacer over the left rear spring.

 

From the SS website:
Front:

1999 Toyota 4Runner front coils from a vehicle made in Japan with a 3.4 V6, 4WD & 16" wheels. (TWO) Pink + Blue = Drivers Side : Yellow + Blue = Passenger Side
Tokico Trek > Master R/T front shocks. (TWO) Lifetime Warranty !
Two: Genuine Toyota Upper Front Shock Nuts, We remove the problem prone Tokico Aftermarket upper front shock nuts and provide Genuine Toyota Replacement nuts.

Rear:

1999 Toyota 4Runner rear coils from a vehicle made in Japan with a 3.4 V6, 4WD & 16" wheels. (TWO) Both coils are the same
Tokico Trek > Master R/T rear shocks. (TWO) Lifetime Warranty !

 

I also installed a set of 99 coils on my 97 4Runner. It made the lift even front to rear so I have added a set of the OME 10mm Trim Packers to the rear to give it a little rake. Was a perfect solution for me and gave me the results I was looking for. Super easy to do. Jack the rear and support with stands, then unbolt the swaybar connection's on the frame, remove lower shock bolt, lower axle, take out spring, add packer to the spring ans re-install. If you have a jack, jack stands, and a 17mm and 12m sockets and wrenches you can tackle the rear of oyu truck.

 

The left and right coils only apply to the front and not the rear. The rear springs are both the same. A gfood place to support the frame is right before the axle notch. Right before the frame curves around where the axle lays. Its as far back as you really can go with the stands being out of the way.

 

Ok - I installed a 10mm OME trim packer over the left rear spring a couple of hours ago. Looks like I got 1/4" lift on the left rear wheel (measures 35.25 now). After the truck was raised on the jack, I had to use a crow bar to get the spring out. I probably should have bought a spring compressor to make things easier.