Back end swaying....

[hrudy18]

About a year and half ago I got a 3 inch body lift on my Ford Ranger. It's only 2wd and 4cyl so didn't really see the need for a suspension lift. Anyways since then I've encountered a problem that is very dangerous when driving. Everytime I hit a bump my back end will shimmy violently. For example, going over railroad tracks will cause the back end to feel like it's moving side to side. On the interstate it does this also except I'm usually going higher rates of speed. So driving has become a serious pain because I'm constantly worried my back end will slip out from beneath me and cause me to spin out or perhaps roll over.

Any advice would be greatly appreciated. It's very hard to describe the problem to some one unless you actually feel how much the back end is pulling.

I have a 99 Ford Ranger with a 3 Inch body lift. Also I have 31 inch tires. No other modifications and everything else is still in factory condition.

A friend told me that the springs might need to be adjusted, but not sure if that is the problem. Another friend told me to decrease the tire presure. So I decreased the tire pressure to 40 PSI on all tires. The max PSI on my tires is 50.

Thanks!

 

[Nate1]

Wow! What tires are you running?! I run my tires at 32psi and to me that is still a little high. Perhaps you have your tires way over-inflated.

 

[snocross1985]

I agree, try lowering the pressure to about 30-32 psi and see if it makes any difference.

 

[hrudy18]

Will do. I'll be honest I'm not really a car buff and was never raised around any. So I'm learning as I go. I'll report back if that helps any.

 

[Alec]

2 other things to check:

Check the body mounts (the body lift), maybe one came loose.

Maybe your shocks are shot.

Just for clarification, the max psi labeled on a tire is just that, the max psi. Most vehicle/tire/wheel combos take 32-35 psi. Usually you follow the vehicle's manufacturer recommendation or close to it, though Ford usually recommends too low a psi for it's SUVs to help with ride quality.