ok so on my work tonight i noticed a real violent shaking when go between 30-50mph, my first thought was a tire problem(missing weight,bubble etc) but when i let off gas or push in the clutch it completely disappears, which tells me it is not a tire problem, if anyone has any ideas of what could cause this it would be greatly appreciated, i just got my truck back from ford after paying a $1200 bill and i really dont want to bring it to them again, thanks alot in advanced

 

When's the last time U joints were replaced?

 

not sure, how would i know they are gone(sorry never delt with u-joints)...also i have been reading some posts saying that the factory weights call fall off the driveshaft( ok here comes a dumb question) does anyone or can anyone take a picture of the weights so i know what im looking for thanks

 

If its not the stock driveshaft they are welded on usually. Mine had a death shake when my driveshaft was bent, it was only at certain speeds. You would slow down it would go away, get back in the range shaking violently, then speed up and then it would be gone again.

 

it just all seems weird i drove it sunday with no problem got up the next day to go to work and there is the shake didnt hit nothing so that is why i am baffled

 

To see if the driveshaft is out of balance you need to find out what RPMs the shaking occurs. Then drive in a different gear at the same RPMs, if there's no shaking it's not the driveshaft. The weights are just a piece of metal welded to the otherwise smooth driveshaft tube. The u-joints can be visually inspected and then with the truck in neutral and the parking brake on (so you don't get smooshed) grab the driveshaft and twist. Sometimes you will see excessive play in the u-joints, but sometimes they are jammed crooked and won't move.

 

thanks sean i was wondering when you would answer