low speed vib after lift

[meatsauce]

i've serched the forum and found some different things to check out. i am hoping some one with a sharp eye can narrow my search for the problem. i just finished a OME heavy+ fr and rr lift. did a knuckle rebuild and rear bearings and seals. she sits a little bit higher in the rear. the pics are with 5 gals of gas ( 38 gal tank )and the spare in the back. future projects include a sweet bumper duel swing arm combo and most likely a roof rack. i'm hoping that the weight will settle it about an inch or so. the problem is, at about 20 mph there is a slight vib/ low freq noise that wasn't there when i took it apart. at first i thought it might be the super swampers ( two of the tires lost there bal weights somewhere down the road ).the original springs were flat fr and rr. it does for the most part, go away when i take my foot off the gas. i haven't taken it over 45 mph. i already greased the u-joints and the shaft was never taken apart. the rear pinion was removed and reinstalled ( for painting ). any thoughts

 

[meatsauce]

pics

here's the pics

 

[Heartworm]

Does the vibration seem to be coming from the front or back? Did you fasten your driveshaft back exactly the way it was removed? Initially I am skeptical that it is the lift. Having said that, there was a recent debate about caster changes potentiating "death wobble". You probably did change your caster a little with the lift. Driving it for a while should cause the springs to settle some, at least it did with mine. Might be good to drive it a bit before you went after a diagnosis.

 

[inkpot]

Howdy! Fill up that gas tank and see if it is better or worse. That's over 200 pounds of extra weight. You can throw in a couple of bags of cement mix or whatever to make the springs settle in a lot faster. John

 

[meatsauce]

thanks for the input. i'll search the "death wobble" and throw weight in the back and check it out. its hard to determine if its front or back. i haven't yet put it into 4 wheel thats why i was thinking the back. i'll drive it for a while and see whats happens. thanks again fellas.

 

[grant5127]

In pic#3 you can see the drive shaft is out of phase........ separate the slip-yoke from the longer end and reinstall it with the joints in align..........

 

[inkpot]

In pic#3 you can see the drive shaft is out of phase........ separate the slip-yoke from the longer end and reinstall it with the joints in align..........

Howdy! Duh, I should have seen that! I went thru that once, and I always try to look at that first, on every driveshaft. Put that rascal in phase and then test drive it. Let us know if it helps. John

 

[weak-link]

x3 on the driveshaft

 

[twstrchasr]

As far as the rear sitting high I seriously doubt it is going to "settle" enough to where it is level (if that's where you want it). My 62 was sitting high in back when I installed my lift and new springs. I ended up taking it to a spring shop and having the rears re-arched . It's not exactly an exact science so be sure to let them know what you are wanting. The first time they dropped the rear too much, then too high and on the 3rd try all was good. They only charged me for one time, btw. Work with them, they are usually wanting to please. I wouldn't have the rear spring work done until you have everything on the rig, so to compensate for any added weight you might add. Do the springs too early and it might end up sagging after you add all of your accessories.

 

[meatsauce]

grant5127In pic#3 you can see the drive shaft is out of phase........ separate the slip-yoke from the longer end and reinstall it with the joints in align..........


i'll align it and see what that does. thanks for the info.