Car vibration

Hello All,
I have a 04 x5 3.0L I converted to 4.8is look. I firstly replaced the wheels tires with a not 4.8is 20" set. After a while I got sick of them and got the 168 style. a week after I put them on I started feeling this vibration at speeds between 45,50mph- and higher. My first thought was that they did nt balance them right, so I took them for rebalancing and it was off so they fixed them but the problem didnt go away, after about three times of going to different shops for balancing the problem still exsists until not I can hear and feel the vibration at even lower speeds.
Ive been doing some research and a lot of suggestions are out there: some refer to the CV joins, others to axles, some to Pinion Bearing and a lot to the differential itself. I have seen some leakage around the differential and wondered if this could be the issue, maybe less or no oil in there anymore could be causing such issue.
I had some thought that the rims could be bad, but it doesnt look like it after inspection. it is very annoying. its funny because even though I know and feel the vibration from the rear, right now I feel the steering wheel vibrate too as if my roters have gone bad which is not true either.

Any suggestions of a starting point to look into this, I think I am in denial about the differential issue and do not want to believe that it could be it or even the axles for that matter.
What do you guys think?
Thanks for the help.

try ur old rims/tires

c what happens

mayb ur tires are damaged on the inside (the cord)
mayb rim bent

I just came in. With the original 18" everything felt and sounded less but still there and noticeable. I do understand the less effect for the fact of calibration issues since I only put the rear ones on to test the rear rims and tires, and the fact that I barely feel vibration in the steering wheel which is the indication I am aware of for a front end issue. So I was running the truck on a 2 20" front and 2 18 rear. I will try the all 18" tomorrow, I doubt I'll find anything different but I'll let you know.
Thanks for the tip.

u shouldnt run the truck on tire/wheel combo that have more than a little bit of difference of rolling diameter

Originally Posted by Gurjit

u shouldnt run the truck on tire/wheel combo that have more than a little bit of difference of rolling diameter

the 4 18" are still showing the same issue. I just put the set of 20" on the rear for a run, for testing purposes.
I think it is down to one of the initial thoughts then dont you think?

cv shaft?(axle shaft)
check ur bushings on the front suspension

I agree maybe a torn CV boot and shaft. I was having the same annoying issue you are having and I changed the tie rods. It still vibrated. Well it was the lower ball joints believe it or not. I ordered new lower ball joints I think $40 bucks each. The problem is the labor my brother went through to put them in. You have to take off the rotor assembly and press out the lower ball joint. Make sure you put the new ball joint in the freezer hours before this process. It will save you tons of time replacing it as you can manually press it in. Remember metal shrinks with cold and expands with heat.

I had a torn passanger side CV boot too. It was easier to replace the whole CV shaft assembly. I put a remanufactured in from NAPA. It still has BMW on it just been rebuilt and only cost $60 bucks and not $300.

Good luck and plan plenty of time if you do the work.

DirtyDan!

i just changed my front L cv shaft
night and day difference
i got a 2004 4.8is with 100km

car would pulse/vibrate @ certain speeds, steering wheel would shake side to side a little bit

my front L boot was riped

new shaft = no more vibration
smooth as a babys bottom