Cheers everyone,

I recently put on some 35" tires on my 2004 RAM 1500 4x4 HEMI.
To reduce the rubbing (wheels are offset +7 and 38mm (1.5") spacers are installed I cranked the torsion bar keys as much as I could.
Rubbing is now gone, but I'm getting a slight vibration when acceleration. Vibration is not present when maintaining speed.
Is there any "cure" for it? Is it due to the drive shafts now running in a "not ideal" angle?
Or is just because they have been in the "stock" position for 135k miles?
What is the best way to fix this issue?

Thanks everyone!

 

From the point of view of the truck, the axles are always the same angle (ish... obviously they'll straighten out some as the suspension cycles). From the point of view of the axles, they're always rapidly bending at the cv joint as you roll down the road. I assure you they've never been stuck at any angle.

Cranking the bars changes your alignment, you're probably feeling different tread contacting the pavement. Take it in to get aligned.

 

Are you sure about that?
For me it would seem like the front drive shafts are changing their angle when the front sits higher?!

 

Yep, steeper angles on both ends of the axle. Of course, those joints become less efficient/effective as the angle increases..... But, they shouldn't be powered when you are on the road in any event. Still, even when not powered, the could possible induce a vibration that you can feel.... just because of the angles they are operating at..... Getting an alignment though, is a good first step.

 

I'm very sure the axles are constantly bending to every angle as they rotate and the suspension cycles. Sure, cranking the keys changes the standing angle of the axle, but every pothole and speedbump you have ever hit has put them at a greater angle momentarily.

 

Key word there is "Momentarily". Cranking the torsion bars puts them at a pretty extreme angle at static (current) ride height.

 

That was I was thinking as well - for sure they get to "every" angle when riding, because of the road bumps and the suspension moving.
But like 99% of the time they are at the same angle/height though.

I checked Rockauto for spare parts and found out that there are improved version with a "sliding center bar" that allows to compensate for the change in overall length.

So there will be some part of the stock axle now being at a somewhat "non-ideal" angle I think that causes the vibrations. Maybe I will try these improved design axles.

 

They also make 'high angle' CV joints/complete axles, but, them fellers just ain't cheap.

 

The special axles aren't that expensive, less than 100$ a piece.
Will maybe try them out and see if that will cure the problem...

 

The ***** are constantly moving throughout the races within the CV joints as you drive, as long as you are moving the axle is never at the same angle. From our point of view sure they look static. The axle however, is bending at the CV any time the wheel is rotating.