Hi everyone - 1st post here. I have a new to me '73 that had quite a bit of work done under previous ownership. I have since had the engine replaced and added a larger fuel tank.
It has a horrible vibration/shake starting around 60 and then gets to its worst at 65. It stays the same up to 75 but I have not had it any faster. I did get the wheels balanced but that did not take care of the issue. What should my next steps be?
Welcome aboard!
Vibrations can be difficult. There are a lot of things rotating. You mention tires, how old are they? They will have a date of manufacture, often tires that are more then 5 or 6 years old and been setting a lot vibrate, even perfectly balanced at the tire shop. And as mentioned previously some tire and wheel combinations vibrate, they just do.
The other thoughts are are the front lockout hubs locked? Is the transfer case in 2wd? Either if of those are in play, more than likely you will have vibrations. Also has the truck been lifted? Pinion angles could be off causing a vibration, we need a little more info.
Lastly it could have a worn driveshaft, joint, centering pin on the cv joint etc that can cause vibration as well.
Welcome aboard and we will help as best we can.