4" lift no vibration

[jboarder16]

4" lift now vibration

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So I just lifted the back (gonna do the front as well) and just took it for a test drive and it vibrates almost imediaty.... This is on my k5 blazer, is this a common problem?? And if so what is the fix? Shim?? Or lowering the transfer case?

 

[crazy4offroad]

Did you do spring lift in the rear or lift blocks? Or shackle flip??

 

[Swims350]

we had a block lift on our 86, no vibrations. I would say not common.

 

[Beatdown Z]

Did you check the u-joints? The increased angle will definitely make a bad u-joint worse.

Also, learn how to measure the pinion angle.

 

[jboarder16]

I did a 4" shackle flip... ya i came across a link to measure pinion angle but i can't find it. does anybody know the link?

 

[78shortandwide]

I would say its the pinion angle. And lowering the transfer case might help but it will affect the front pinion angles on the front drive line.

 

[jboarder16]

Hmm that's a good point but I just stopped by the truck and the transfer case to driveshaft definatley is on more of an angle then the rear joInt

 

[78shortandwide]

My friend has a 74 blazer with a 6" lift he dropped his transfercase almost 2". Those blazers have really short rear drivelines so dropping the tcase should fix the vibration.

 

[towman]

had to drop my transfer on a k5, do a search this was covered in depth not to long ago

 

[sean1960]

The shackle flip changed your pinion angle just enough to cause the vibration. Lowering the transfercase should help. The transfercase and the pinion need to be close to the same angle. The CV joint in the front drive shaft will compensate for any change in angle at the front of the transfercase.

 

[jboarder16]

I just finished putting 3/4 solid piece of steel on either side and it took the vibration right out! So happy that is gone and I love my new he's shocks and how the back feels alot firmer than before! Thanks for everybody's input

 

[jboarder16]

So driving the truck more I still feel a little bit vibration between 30 to 40kms. It's nothing major but if u really feel for it u can feel it. Do u think I should wait to c when I lift the front if that affects it all or should I lower it another 1/4?

 

[Beatdown Z]

Buy an angle finder and adjust the pinion angle, not the drivetrain angle. Even if you lower the trans to get rid of the vibration, your pinion angle will still be off. I'm willing to bet you'll need AT LEAST 4 degree shims, if not more.

When I put a shackle flip on my '99 Silverado, I needed 8* shims to get the angle where I wanted it...

WFO Concepts has nice steel shims for a good price.

 

[sean1960]

Drop the transfercase more. The angle of the transfercase and the pinion angle have to be close to the same. If you buy shims buy the steel ones. You have to bring the front of the pinion back down where it was. The shackle flip tilted it up at least 4 to 6 degrees. The transfercase angle and the pinion angle need to be about the same.

PS when you lift the front of your blazer it won't affect the angle of the rear at all.

 

[jboarder16]

That's what ithought but the driveline guy told me to wait and c if liftin the front affected the vibration, so maybe I'll drop it a 1/4 more and see how it goes, either way I love the way it feels with the flip plus new shocks it feels like a whole new truck im just anxious to put in the front shackles to lift the front a little and then go to a trail!