Lowered 1500 Silverado

[Tracy224]

I installed a DJM 3-5 loading kit, axel flip notched frame ect.

2005 Silverado standard cab " long bed" with a one piece drive shaft.

All is well with the parts and install my problem is I have a vibration under excelleration that starts about 55-60 mph. Just cruzing at hwy speed you don't feel it until you accelerate or an incline in the road. I have the drive yoke from the tranny and rear end yoke at the same degree, parrel with each other. Every pic I see about pinion angle shows them parrel. But it also shows the drive running "down" hill to rear ended. My drive shaft I guess because of the flip kit and 5 inch drop now my drive shaft is going up hill to rear end. Any suggestions? I would like a degree or something presice to do and not like some have told me. " just move it till it stops"! I'm very close just wore out on trying to figure it out.

Thanks

Edited April 23, 2016 by Tracy224 (see edit history)

[someotherguy]

Is your driveshaft at an angle, or is it straightened out from the lowering? When it's straightened out, that's when you'll get vibration, and you'll kill the u-joints quickly.

 

I don't know what parts DJM includes in that kit, never cared for their flip kit, but if it's their "adjustable pinion angle" design then good luck with it.

 

Here's one old illustration from the net showing desired driveline angle

 

Since you have a one piece shaft it's not like you can space the carrier bearing, so you can adjust at the rear to bring the pinion yoke down and increase the angle. You can also shim the trans mount if needed.

 

Richard

Edited April 23, 2016 by someotherguy (see edit history)

[Tracy224]

Yes it is the adjustable pinion. It's only vibrates under acceleration between 55 an 65. You can floor it at 70 and cruz at 80 with no vibration. The diagram you sent is what I have, parallel front and rear with the driveshaft going up to rear end, not traveling down to rear.