Vibration at 60mph and up very noticeable everything rattles

I bought this Cherokee after destroying my old one, this new one is a nice 2000 classic, everything is sound and runs great at low speeds and offroad but everything over 60mph starts to shake and hum

I bought it with the lift so i dont know what it was like before, its got all the spacers on the transfer case and the add a leaf, and doesn't seem to be the problem, feels smooth at 50 55 mph

and while raised up off the ground on the rack it'll go 100 without any of the same vibration
I have had the tires balanced aligned, I am using Yokohama all season tires like id say 15 percent offroad

I really have no idea what it could be I really wanna figure this out

 

Need more info.
Lifted? How much?
SYE?
Tire size?

 

Speed vibration most of the time are caused by one or two different things, 1 tires out of balance. Look into dynamic balancing your tires especially if you drive on road and go off road. The other is bad u-joints/ front driveshaft angles.


Like Frank said need more info.

Also Please in your statement you say you took your jeep to 100 on the lift with no vibes? Next time you do this take a video.. and post.

 

why would you ever take it to 100 mph on a rack? sounds dangerous as hell!!! you said the vibes were at 60 then why take it to 100 mph?

x3 on more info needed

 

I had front end vibes that began at 55 mph, got an alignment and 90% of those vibes were gone.

 

my cherokee had bad vibs like speed woble at 55 to 60 got an alignment and bye bye no more vibs for like 8 months

 

Without the the full weight of the rig on the tires your test on the rack means nothing.

 

Do you notice it in the steering wheel, seat or ??? Steering wheel = front,
seat = rear. If in just one of the above, swap out tires and see if it moves
to the other. Could be a bad tire. I had some Dunlaps a couple years back that felt
like I was on one of those fun rides at the park. Had the dealer swap them all out
and problem went away.

 

I have had the slip yoke checked at the shop, its got a 3 inch lift kit

I brought it up to 100 as well as trying at 60-70-80- and 90, at every speed above 60 I get a horrible vibration in the seats the wheel everything, there is not anything not effected by it, the cup holders, the cd player and even me when im sitting in it. It is a general overall HUM

I have had the transmission checked the drive shaft, the transfer case.

I have tried alligning the tires and blanancing and ALL of that nothing seems to make even a slight difference, I have tried once changing the rubbers on 2 of my tires to 2 yokohama and 2 all street tires, i think just the standard goodyear while using my rims
Nothing made a difference though

When they were putting my yokohamas back on and i noticed how much trouble they had with one rim they blew one of their machines trying to pop the tire on the bead

Could it simply be that one rim causing the vibration, I want to try 4 new rims and tires next and see what happens

if i do that should I fork out the cash for another alignment before the test?

 

is your SYE a hack and tap or a true short shaft w/yoke?

 

Honestly I dont really know, I am not familiar with the different types of set ups

can you give me an idea of what each type of set up would look like coming from the transmission?

Also BTW i have a skyjacker lift kit

 

is a hack and tap like where you cut the original to add in the spacer with the extra length by welding or bolting

because it looks to me like a short shaft nothing seems cut

besides I have had several mechanics take a look at the drive shaft and the transmission and the transfer case and check the angle of the DS

but everything seems to check out ok

I really cant figure this out
Just waiting to hear from my friend to borrow his rims and tires

I am getting so frustrated with this RUMBLE since i got the f*****r
Im getting ready to Trade in my JEEP for this old 91 SUBURBAN 4x4 5.7 v8 that thing is a beast but still feels smoother than my rattlebox jeep