2005 6.0 4x4 106000 miles

I broke down a month ago coming back from <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com</st1:City>San Diego on I8 and had to get towed back into Phoenix<ST1</ST1. I lost 5 injectors. The first truck could not pick it up so they had to bring in an old truck. They pulled off the driveshaft and tied it up for the flat tow. Now I have vibrations at 70 and above.
Should I change out the U-Joints or try to flip the drive shaft 180 and try that first? I am getting ready for another road trip and need to fix it this week.
I took it to Sams Club and had them re-balance the tires yesterday to take that out of the equation.
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We used AAA for the tow – only took 2 hours for them to show up. 5 hours to actually get a truck that would pick up the beast. It was fun watching the drug smugglers off in the desert midnight and having 5 Boarder Patrol vehicles to watch over us with the advice that if I have heat, keep it on me! I LOVE our boarder in AZ.

 

I'd flip the driveshaft first if it isn't much trouble for you. But that being said, no harm done replacing joints at your mileage.

I had a similar issue at that speed yrs ago but turned out to be a "defective" drive shaft (after I dragged a dead 4000lb boat across a beach) and my extended warranty replaced the driveshaft, problem solved.

 

might as well clean and stuff the slip joint with some heavy duty synthetic grease while you have it apart. Our '00 vibrated on acceleration simply because the slip joint grease was insufficient and/or gone.