Vibration at a certain speed

Hi everyone, I have an issue with vibration on acceleration and deceleration at around 90 to 120 kmh as well as a different kind of vibration, more of a wobble during acceleration at around 60kmh. This issue started for me when I got a 2 inch lift. I've been to a number of different mechanics as well as a drive line specialist to resolve the issue with no luck. I've got the drive line balanced one of the u joints replaced as well as both cv shafts.

Has anyone experienced this kind of issue after a lift and has anyone got any solutions ?

hi,
Sorry this could be a difficuly one, if you have already been to the experts. So maybe its bad to assume but you would think they have checked the obvious things.

is the driveline indexed correctly. Ie uni joints in the same plane?
Also, grease both fron and rear splines?

Failing these checks, best place to start would be understanding what was done during the lift. Who did it, and what did they do.

Was it replacement coils in rear and wind up the torsion bars at front?
if so, I would start by winding the front back down (can be done at home) until driveline angles back to original and test driving to see if it made a difference.

The type of tyres makes a big difference to balance and vibrations. Tyre wear of off road tyres on mine caused a lot of vibration at certain speeds. Regular wheel balancing helps. Lifting the van certainly throws off the suspension causing more bouncing and makes the shocks less effective. Steering and tracking is affected. I had camber adjusted to correct some of this on the front wheels.

Hi, You mention a lift but not whether it was just that or if new tyres / wheels were fitted at the same time. The lift will change the angle at which the drive shafts sit but of course that should not be out of the normal range of motion for them. Both of the issues mentioned could be due to balance and effects described by Hiace Hobo regarding the wheels tyres themselves and/or their interaction with the raised suspension. I'd be checking those tyres out. You could rotate wheels front to rear etc to see if the effect changes. Good Luck!