Help diagnosing my suspension issue (leaf springs, coil springs, bushings?)

Hey everyone. I have a 1999 tacoma 4x4 with 230k miles. Car is running great. I've put in new lower control arms, lower ball joints, rack and pinion bushings, struts, and shocks. However, the suspension still feels weak to me. When i hit bumps in the road, the car dips into the bumps. Often times, if there is a series of bumps in the road, the wheels feel like they are jumping which result in my tires landing on the road and gripping in a slightly different direction. At highway speeds, if i hit bumps the truck will often sway before coming back to normal position.

I measured the distance from the ground to the wheel well on each tire, and each is 36 inches except for the back right, which is 35.5 or so.

This all leads me to think that I need new coil springs and leaf springs, but I want to be sure that is the correct thing to do. I went to Midas for an oil change, and they said the springs were fine. However, I don't like the uneasy feeling I have driving this truck with the above symptoms. I'm hoping some of you will have the experience to know what the best bang for my buck is on making the handling better. Maybe its just the leaf spring bushings rather than the full leaf replacement?

Thanks in advance!

 

What struts/ shocks did you get?

 

I got Bilstein B6 4600 Monotube Gas OEM

 

The Bilstein 4600s were a great choice. It could be that your springs are worn out- they don't last forever. There are a few other things to consider though- what tires are you running, their condition, and what pressures are they inflated to?

The only real answer to the PSI, is to do a chalk test, but in asking that question, we're trying to determine if you're running excessively high or low pressure. Low to mid 30s is about average.

 

Yeah good point. So my tires were about 25 - 30 when i went to Midas for my oil change. They are now 35 and they feel worse. They are slightly old tires, from 2012, but have good tread on them. Im not sure that the tires would cause the swaying feeling i get at highways speeds?

 

Did you reuse the spring? That could be the issue since they don't retain their spring rate through the life of the vehicle.

 

Yeah i made the stupid mistake of not replacing springs when i replaced the struts. My mechanic didn't even mention that its a good idea :/. But definitely would have been the right thing to do

 

I went with OME880 w/ Bilstein 5100's. I like the they feel, but I have a 2.7L so it might feel even better if you have the 3.4!

 

Not sure where you are located. But in general, I don't have a high expectations for full service shops like Midas/Les Shawb, etc... They are really just there to move vehicles in and out as quickly as possible. You may want to try a regional sub forum and find a more reputable shop.

That being said. As old as your truck is, basically every piece of rubber in the suspension system and driveline needs to be replaced. Even something like the transmission and motor mounts, body mounts etc... They all play a part in how the truck behaves and feels on the road. It's good that you've ticked some of the larger items off, but they all need to be looked at eventually.

 

Do the OME880 add a lift? And yeah i have the 3.4L

 

Pretty much any spring you get, front or rear, will result in some lift relative to your current worn out springs.

 

Yeah makes sense. But i guess i wouldn't want the front to be lifted, while the back sags. Would i be able to solve that just by replacing both the front springs and the leafs at the same time?

 

yes it added a little on my 2.7. it will lift even less on your 3.4 (which is perfect if you want a subtle lift)

 

Yes and no. The rear springs tend to sit high for a bit when they are new. Most folks suggest the General Springs packs, some have been happy with them, some haven't.

 

From your tell I think you need new coil springs.

 

Bingo - I'd take it to a reputable alignment shop. One that specializes in 4x4 (lifted) if possible. I don't have much faith for lube joints either. Plenty of horror stories on forgetting to tighten the oil filter or even put the oil plug on. They work in a pinch but it's a gamble!