HI all,
my first post on this forum.
I am going to build a hummer, and I am wondering what everyone's experience is with lifts?


Ive lifted 5 trucks now and a few have been problematic.
I ran into crazy driveline vibrations on a jeep grand Cherokee, and an 2012 Ram 1500 ...had to sell them both afterwards. (Both ****ty RCX lifts)


I don't want the same issues with my new hummer. (2004)


I was thinking rancho 4" and 38s
or the bullet proof or fabtech on 40s


for the lifted guys, any problems with driveline vibrations?


any advice or insight would be great.


thanks for your help

 

If you go Bulletproof, you have the option to buy they're driveline and it comes balanced and made for that lift.

 

I have a 06 H2 with a Fab Tech 6" lift with 40" Nitto Mud Grapplers...came with a longer drive shaft...I have no vibration issues what so ever!

 

Jeeps and to a lesser extent the dodge has a common issue with a "death wobble" I've had to deal with them at my shop here and am sick of it. You can look on youtube under death wobble and most jeeps and some dodge trucks have the issue. the dealer won't do anything to fix it.

 

ya our Jeep JK ZJ had a wicked death wobble, got new adjustable control arms and everything...never did get rid of it..
I was a PITA, and very disappointing.


I don't want my hummer to turn out like that......


seems like Fabtech and Bulletproof are both good kits.

 

haha oops I mean GC ZJ

 

I have the Rancho 4" on 40's and and did great until I replaced my Toyo MT's. My issues are tire balance issues though. I just need to put about 10 ounces of ceramic beads in the tires and it should be back to normal.

 

i have done alot of lifts through the years on Jeeps , Fords , chevy and IH , granted not as many as i did when i was young LOL .

for the most part wobble . If everything else is in good shape ,comes from ending up with the wrong angle for the axel. extreme cases would be in Jeep and the Scout 60-80 models where someone did a shackle lift and then did not put in the proper Deg shim so as to re align the axel .

When it comes to vibration , alot of times its do to bad driveline angles where the angle from the pinion or the output shaft is to steep after a large lift . In which case having a balance DL isn’t going to change anything .

One can go to the existent of rolling the axel . But concerning the front axel , you can end up with the DW if you do not shim back to acceptable angles . Rear axel doesn’t really IMO mater as long as you don’t end up rolling it to far and effecting the breaks or the lubricant in the diff . Some guys also used to drop the angle of their tyranny a little. But that also could cause complications .

The easiest thing IMO is to just have a CV joint added to you DL and then not worry as it will take care of the angle issue .

Another issue with vibration can be caused by your DL’s not being in synchronized..
Very common issue when speaking of multi shaft set ups that are often found on larger trucks .
But I have also found the same to be true on vehicles with full time TC Boxes or non lock out front ends where the front DL is always turning .
Why it maters , I don’t really know and in some cases it doesn’t . but I have had luck removing or at least’s reducing lift vibrations by syncing up the outputs of the trany and the transfer when nothing else seemed to work