Lift Vibrations

This. There is a good long thread on here about this. Start with shims as they are nothing but good. Next would be carrier drop, but that increases the angles at the first half of your drive shaft as well as decreasing angles to the rear diff. I put in 2.5* shims during my install with Dakars and have had no vibration issues.

 

RPMs don't matter because the issue is most likely the rear drive shaft. That rotation is dependent on speed, not gear.

 

I don't understand. The first part of your driveshaft - transfer case to carrier bearing - did not change angles whatsoever. If they are telling you that the angles need to be adjusted between T-case and carrier bearing, they are wrong. It is only the rear portion of the drive shaft - past the carrier bearing to the rear pinion - that changed angles. Leave the carrier bearing alone and just add shims for a start. Shims rotate the rear axle up, reducing the angle at the carrier bearing rearward and at the rear pinion forward, but do not affect anything else. The only angles that have changed are the rear carrier bearing back to the pinion in the rear, and CV angles - diff to hub - in the front.

I wouldn't worry about the front shaft for now. My experience has been that 90% of the time, the rear is the cause of lift vibrations.

 

Are you sure this isn’t the known symptom of the stock tuning where the engine changes to the different cycle and it almost feels like it’s struggling to get fuel?

 

Not sure. Just weird that it would start after the lift yanno? Maybe because of the increase in tire size.

 

The second set of angles on that piece of paper was just what they recommend getting to.

My rear diff is already at 5.5°. Wouldn't adding shims just increase that?

 

Adding shims rotates the pinion up, reducing the angles.

 

Hmmm.. well I guess it depends on which direction you orientate them.

 

LOL. That is true, but I would suggest pointing them forward.

 

Order a set of billet aluminum or steel. I think mine were $30. I wouldn't suggest the slotted kind either. You will have to drop the U bolts and separate the axle from the leaf pack a little to install them, but I have seen the the easy-install slotted cast aluminium kind break. 2.5* is probably the maximum you can add without needing bolt head spacers. The center bolt head should go all the way through them into the axle base. Head spacers are really just washers that are the same diameter as the bolt head to give more depth to the bolt head.

 

It's not a hard job though if you have the tools, mostly jack and stands, ratchet and sockets, and a torque wrench or well calibrated hands. Maybe like a 3 beer kind of thing.

 

Here's a list of things that you can check out:

https://www.tacomaworld.com/threads/stuff-that-breaks-after-installing-a-lift.667252/

after reading the list, makes me hesitant to get a lift..haha

 

I blame these guys on IG that run long travel kits on 35s and never seen to have problems. Giving us more normal people false hopes and broken dreams haha

 

Honestly, that's why I would recommend getting a local lift install weekend going and buy the beer and pizza to install it instead of a shop. Have a few guys over that are familiar. That way you can really see what's going on and how it all goes together and see what the potential issues are and how to address it. I would recommend shims installed with every lift. The OEM leafs have shims, maybe a 1*. If you were close to me, I would help toss them on. I'll bet you can be fixed up in an afternoon.