I've installed a Skyjacker 4" lift kit to my 97 4wd Super Ranger, wow, what an experience for a novice.

Initially the rear looked way too much higher than the front so I removed the stock 2" blocks. The rear is now only slightly higher than the front.

The leaf springs in the kit came with shims attached.

However, when accelerating quickly there is a LOT of vibration. I finally took it to a professional and his thoughts:

- the drive shaft is almost an inch farther forward than it should be. We measured the wheel base, door label states 125 and it's about 124.2.
- the pinion angle is not right
- possibly the leaf springs are shorter than the original (front bolt to center pin).

He now has my old springs and will measure them tomorrow and compare.

Anyone seen this problem before?

 

is your truck a super cab or a reg cab?

 

super.

 

did you drop the bearing that supports the drive shaft?

 

If there is no pinion angle shim, vibrations are no suprise, this pinion angle has to be off.

 

Nope.
I'm assuming you mean the fixed support where the front short piece of the drive shaft meets the rear longer piece.

 

What's a "pinion angle shim"?
Is that where the drive shaft meets the rear axle?

The leaf springs still have a shim. We considered removing it to change the pinion angle.
Possibly the drive shaft was always far forward, and the lift kit pushed it just enough further to cause the vibration.

 

your problem is your driveshaft is running at the wrong angle without either dropping the support or running a one piece drive shaft(your best fix)

 

I have the skyjacker 4" lift leaf springs on my truck. There is no vibration and the pinion angle is fine! Did you install the leafs backwards? The pointed end of the shim needs to be forward. rear of truck > front of truck

On a side note, Skyjacker screwed up and sent me the wrong leafsprings when i ordered them a few weeks ago... i put them on and the center pin was too far forward causing my pinion angle to be screwed up as well as my rear wheels to be too far ward. just a thought.

 

Yea, they are on the correct way.

Funny about you getting the wrong springs. They first sent me springs for a Dodge 2500, which obviously were way too hefty and too long.

The original springs did not have a shim, so why do the new ones?

 

I saw screw having a vibration and just go with a one piece. I've done it and I don't have even have a lift yet. Its pretty easy. The hardest part I found was getting that center support sections out. You have to grind it down and beat the **** out of it to get it out there. Then it bolts right in. BUT!!!! before you go out to the junk yard and just grab one be sure to get a measurement on the flange that attaches to the transfercase. i ended up getting one with a bigger one but that was easily fixed but swapping a part from the old drive shaft. I'll show you in a picture if you want as to what I did to create my custom driveshaft.

 

Well the first ones they sent you for the dodge probably didnt need anything to correct the pinion angle. The ones for the ranger do...

 

The leaf spring shims have been removed and the vibration is much better. But it does still vibrate when accelerating quickly in 1st and 2nd. At least now I feel the truck is usable, after 3 long weeks of lifting.
I'm hoping after a couple of months the springs will settle a little bit and the vibration will diminish.
If I drive gently there is no vibration.
Thanks for all the ideas.