yeah i am adding to the driveshaft thing, if you don't put loctight, like ford does from factory, after taking the bolts loose, they will back out again every time. in my 95 i did not use it and i could go 100 miles and the shaft would be as loose as a goose. i fixed it. then in my 89, it started to viberate for a few days and i thought it was nothing so one day i was fooling around and i stomped the gas in 1st and bang bang bang, my driveshaft broke loose. i thought i had enough power to break all 4 bolts off but i looked and only one was broke and there were none there. it was messed up because all that day and the day before i was racing and powerbraking and nothing happened.