4/6 drop on stock gmc 20's.



However, now i have a few issues... now I have a grinding? type noise.

Not rubbing anywhere... but A) whenever i'm going down hills...I hear a noise similar to that of if you get to close to the shoulder... and B) whenever I let off the throttle...there is a grinding type noise coming from somewhere underneath the truck. Possibly around the area of where the driveshaft goes into the transmission.

Now, the driveline fell completely out during the install.. But we placed it back in... (1 piece driveshaft)

So what gives?

Few people have suggested that I may have a bent disc brake shield...that might be causing problem A.

Problem B is still up in the air...

Any help?

 

Is the yoke on the driveshaft pushing into the boot of the seal on the tailshaft of the 4L60e?

Did the drop kit come with a transmission mount shim or axle to leafspring pinion angle shims?

I'd roll the lip on the rear fender/bedsides for sure. And I'd also check out the topside of the underneath of the inner fenders, my 22"s with 265/40-22 on my 04 with a 2"/4" drop don't tuck nearly as much as yours and I rub the inner fenders

But that really does look badass, good work

 

if you dont get it figured out by friday we'll look at it when we fix the camber.

 

putting in the driveshaft upside down (sounds stupid i know) has been known to cause vibrations, so you might want to take the d-shaft out and rotate it 1/2 turn and put it back in.

 

pinion angle is my guess.

 

I guess its a pinion angle too, but ud get lots of shaking at speed if thats the case. If that doesnt solve it, check the pinion bearing and pinion itself. I had a whine/grind when gliding to a stop and turned out my pinion was scrapped along with the bearing (got REALLY lucky it didnt take out the whole rr end!).

 

Looks good! I would make sure it's not the driveline rubbing on frame. It gets pretty tight with a 6" flip.

 

I also agree check the pinion angle..

 

Driveshaft needs to be shortened.............

 

What flip did you use? Mine was adjustable so I pointed the pinion at the tailshaft of the trans and I dont have any vibrations. I dont have any noises other than my tires hitting my inner fender well on some bumps.