Re: Vibration at 65-70mph? Ideas?
Sorry, I wasn't meaning a weight on the driveshaft, but hanging from the transmission/transfer case crossmember. Attaching a pic for reference. I know without those, sometimes a high pitch hum can come through the frame. I'll attach a pic.
If it's a high pitch vibration, it could be the splines. Has the slip yoke been well lubed/packed lately? That can cause some vibration. If you're sure it's not tires, and the shaft has been balanced, I would consider the yoke packing as one cause. Check for free play on the output shaft of the tranny/transfer case and on the pinion of the axle. If those bearings have up/down/side play it can cause vibration like that. Otherwise, maybe make sure your transmission mount is good, because if it has allowed your tranny to slip sideways too much, you could get a mis-alignment.
2004 Excursion 6.0
New HPOP/HPO system o-rings; Updated standpipes and dummy plugs
EGR delete; Rebuilt oil cooler; CCV collection mod
VR Black Diamond head gaskets and ARP studs
Oil and coolant bypass filters; Shell EC-1 coolant
Rebuilt turbo; 250 amp alt; 6000 watts of brain scrambling
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