2003 F250 CC 4x4 slight vibration
'03 F250 7.3 CC 4x4 auto. 135,000 mi.
Just as the title states, I'm experiencing a slight driveline vibration. Nothing severe, but I'm picky. I hate stuff like this. About 30 mph and up to about 50 it has a slight vibration. Definitely driveline related-no vibes in neutral, low gear, low range in any gear, etc. Just starts in about 30-35 mph and kind of goes away about 47-50 mph. Took it to the local Ford dealer-tech said it's "not unusual" and "not cause for concern". I've removed the driveshaft (marked everything) and checked the joints-they are all fine. I believe them to have been replaced at one point as all 3 have grease fittings. Addressed the slip joint (was free, but I greased it anyway). Carrier bearing assembly is nice and smooth-nothing out of the ordinary. Reinstalled everything. Then I found a TSB that addressed this issue, has to do with the angle between the front & rear shaft. So I dug out my inclinometer and checked them. Front shaft it 5.4° and the rear shaft is 8.9°. TSB said 0.5 to 3.0 difference is acceptable. I'm assuming I'm doing this correctly....check the front shaft's down angle, then check the rear shaft's down angle and find the difference. I'm getting 3.5° difference. My question is-do I just remove the carrier bolts and add a shim between the bracket and the carrier? (never messed with 2 piece shaft before....)
The only thing out of the ordinary with the truck is that the front stub shafts are worn out. Hubs have been replaced at one point (they are Timkens) but they didn't replace the stub shafts. They are loose, left side quite a bit looser than the right side. I'll address that in the coming weeks as I can afford to. I would not think it would have any bearing on the vibrations as the stubs and axles don't turn while in 2wd. Am I correct?