07 Yukon XL - Shake After Lowering Belltech 2-3/4

[nelsduramax]

Just lowered using NorcalSS Beltech kit. 2" up front, full 4" in the back.
Has Concept 24 wheels with 305/35R24.
Aligned after the kit was installed. Here are the alignment measurements.

Left Front;
-0.3deg Camber
3.7deg Caster
0.04deg Toe

Right Front;
-0.1deg Camber
4.2deg Caster
0.06 Toe

Total;
0.10deg Toe
-0.01deg Steer Ahead

All the stick on wheels weights are still on the rims.
Did not have this shake when these wheels were on prior to lowering.
Currently shakes at 67 mph and above.

Thoughts.....?

 

[felixgun]

Maybe you need to get your rims/tires re-balanced?

 

[soulsea]

Do you know if maybe you need hub centric rings for those wheels?

 

[NORCAL SS]

if you did a full 4 inch in rear you need to cut the bracket off the frame. Just could be the rear end sitting on the bumpstops and if the wheel balance isnt dead on vibration could be enhanced

also at the full 4 inch level i would look into the djm hardware kit. prevents bind and will make ride better. ALso your rear swaybar endlinks are prob pointed to the ground. The shorter djm links will bring them back parallel to the ground which will help cornering and ride.

 

[nelsduramax]

Can't be the wheels out of balance. I drove about 125 miles on the freeway to my brothers house at stock height with the Concept 24 wheels on and had no vibrations what so ever.

Tony - Which bracket are you saying has to be cut off?

Should I just try and trim about 1" off the belltech bump stops?

---------- Post added at 09:05 PM ---------- Previous post was at 09:03 PM ----------

Do you know if maybe you need hub centric rings for those wheels?

I believe that these wheels are hub-centric. There is no clearance between the hub and the center bore of the rim. The lugnuts are not what is centering the wheel.

 

[NORCAL SS]

at 4 inch level you need to cut the bumpstop brackets off the frame no way around it. That will improve ride greatly.

you need to cut the bumpstop bracket off the frame so looks like this after

 

[nelsduramax]

So at 4" drop, there are no bumpstops being used? What if the rear end bottoms out or it can't travel that much?

If the 1" spacers are used, then the bump stop brackets will not have to be removed?

What does the DJM HWare kit do (besides shortening the swaybar links)?

 

[NORCAL SS]

No at 4 inch level i use the djm hardware kit which I include new bumpstops with and you get a beter ride. 3 inch level you can just use the set up you have now for more travel but if you load it up it will sit on the bumpstops. I cut off the bracket on my truck at 3.5 level rides great.

djm hardware kit comes with trailing arm relocators
different design shock extender (you can sell yours and make money back)
left/right endlinks which also move axle over
I include new short bumpstops for the rear

 

[nelsduramax]

Thanks for the info Tony.

I looked under the rear end today. I am now currently just resting on the bumpstops. The top 3rd of the coil is compressed. Not sure that the coil is supposed to already be compressed that much at ride height.....? When I completed the install, I had about 3/4" clearance from the bumpstop to the contact pad. Might have to put the spacer in....?

I think this weekend I am going to put the stock rims/tires back on to verify that it is not a wheel balance issue.

 

[NORCAL SS]

Normal for the top coils to touch they have been like this since late 99 when the 5305 springs came out.

i would cut the bracket off if you plan to keep it where its at now. Ride will improve 10x