Mine did the same thing after putting 35's on. Sometimes the tires need to be rebalanced as soon as you hit hwy speeds I had the tires rebalanced 2 days later and they were taking off as much as 8 oz. off on front right tire Take it back for a rebalance. I have a 3.5" RE lift which is more like four. Drive shafts are fine. Hope yours are too

 

With 4.5" of lift, you're going to want adjustable front lower control arms to increase castor and adjustable track bars to center the axles. Most complete kits with this much lift include these items. Also, I would keep a close eye on the drive shaft boots.

 

I had mine rebalanced 2 days later and it does the same thing so I still dont know.

 

I am having some issues myself as of yesterday...I also have the BDS 4.5 and I am running 37's. Yesterday morning while driving on the freeway I started to feel a faint knock on the floor board...It's not a constant knock it's more random..I checked the drive shafts and they are not loose nor do they have any play in them whatsoever...It's weird...sound like something is loose somewhere..I am going to call BDS first thing tomorrow and see if this is something that is common and what they say about the drive shafts or if they have any suggestions. Keep you posted on what they say. I'm hoping it's nothing serious...

 

My ride is quite as can be. Nothing making any noises. So its probably just something loose that you didnt tighten all the way like a sway bar linkage or control arm. Something simple. Just go over everything again. Shouldnt be making any noises. As to the little shaking over 65mph I have no idea! And god is it BUGGING ME.

 

Were youre tires just spun and balanced or road force balanced? Spin balancing works on lighter tires, but when you get into big meats you really should road force balance them.

 

They were just spun and balanced what does road force balancing consist of?

 

Check your control arm bushings. Have someone watch your front upper control arms as you drive forward/backward slow and stomp the brakes. If there's play in the bushings you should see the arms move. Or grab the arms and try to move them.

 

Well, I took my rig to my guys today and had them go over everything to make sure nothing was loose...the 2 front lower control arms where just a little loose and they re torqued everything and they also checked my driveshafts and they said they looked fine..the boots were good and there wasn't any play in them what so ever...Well, after I left, it started doing it again, so something is still going on... I needed an oil change so when i was getting that done, the guy comes out and tells me, "hey did you know that the last time you had your oil changed they put 10w 30 in instead of 5w20..I said no..they were suppose to have put in the right shit...then he said whens the last time you had your diffs checked and oil replaced...I said I had the front and rear replaced the last time the oil was changed...He showed me what came out and it looked like dirty chocolate milk...WTF...super thin junk...Needless to say I am pissed...Anyways, ended up getting it for free...But does any of that sound like it could have been any of the problem..like maybe a knock in the engine or gears in diff due to shit oil in there? sorry so long winded but any help guys/gals would be much appreciated cuz this is driving me crazy..and if I don't figure it out I am going to have to leave it at the shop....PLEASE HELP!!!!!!!!!!!

 

How was he able to tell the difference in the oil viscosity? He taste it or something. As far as the diff fluid, have you been through any deep water or mud holes lately , have you checked and made sure the diff vent lines are still connected and haven't popped off.. Water mixed with gear oil will give it a milky appearance.