Vibrations in driveline as a result of aftermarket springs.

[XwerX]

For those that have aftermarket spring installed, have you noticed vibrations that start around 58mph? I have Geiser springs installed front and rear and have a weird vibration. The truck has been at the dealer for a week and today I was informed of the following…

“Yes they found some things - so you have aftermarket springs on the vehicle and with the 2.5 inch lift on the vehicle it changed the pinion angle of factory specs of .5 to a 7.2 degree angle which is causing the vibration you are feeling with the vehicle. If you convert it back to stock we can reevaluate the vehicle but at this time there is nothing further that can be done until it is back to stock. You are not being charged for the diag to get it looked at.”

 

[thatJeepguy]

I mean they’re probably right. Pinion angle increase of 7 degrees is high. 1-3 is fine . Tail shaft to pinion @ 7 is high asf. Does it get worse with flex?

 

[XwerX]

I know a 7 degree increase is high. I find it odd that a Geiser spring changes the angle that much. I haven’t noticed the vibration getting worse with flex.

 

[thatJeepguy]

I know a 7 degree increase is high. I find it odd that a Geiser spring changes the angle that much. I haven’t noticed the vibration getting worse with flex.

Its my first ifs truck but axle from front diff to hubs is where the increase is most prevalent.

 

[Nex]

You can either shim up the diff or drop the t-case some.

 

[XwerX]

Is this a known issue with Geiser springs?

Honestly I don’t think the springs are the issue. I have many years of building and troubleshooting modified trucks. I feel this is the easy way out for this particular dealer.

 

[taquitos]

Lifting does change alignment a little so could just need to be realigned a tiny bit. For anything beyond stock I never trust dealers to do that right.

 

[GCATX]

Probably will need some adjustable rear upper control arms to dial it back in. Kind of surprised 2.5" lift resulted in 7 degree change though. Maybe throw a bunch of weights in the bed, or whatever, and see if dropping it back down smooths it out.

 

[XwerX]

The dealer was just trying to blame the rear springs on the vibration. I swapped the factory springs back onto the truck and the issue is still present. My instinct says the driveshaft is out of balance.

 

[BoostCreep]

My next move would be to rotate the tires front to back. If it makes no change, then yes I would assume driveshaft balance.