I have an 84 150 4X4 with 351W. I just started noticing this vibration I get when I get to around 30 mph or above, that seems to coinside with hitting small bumps. I can feel it coming through my feet. Its a little hard to explain but it feels/sounds to me like somthing with the drive train rather than the suspension. I'm thinking U-joint but I don't know. Any ideas from anyone would be appreciated.
Thanks

 

Hi, I had the same problem with my 84 F-150 4X4...check the front shaft....my u-joint was gone in mine..and it was hitting the cross member for the transmission on every bump in the road!..hope this helps!

Bishop
84 Ford F-150 4x4, 300, from red to black and box to flat bed!

 

Thanks for the post. How can you tell if a U-joint is bad, just check if it has play if you wiggle the shaft? They are not that hard to replace are they? I never changed one out before.
Tom

 

Hello,
We have a 1968 fastback mustang with a 428HP 302 and when we get about 80km/h it does the exact same thing. We dropped the shaft your 2 u-bolts and 4 nuts with washers and inspected the front universal joint. We found that we have drove the u-joint without proper grese and it heated the little pitman bearings and caused the vibration. Hope this helps!

 

[updated:LAST EDITED ON 17-Apr-02 AT 12:56 PM (EST)]HFLU,

Is your truck auto or manual? Does the vibration occur when you accellerate, coast, brake, etc.? Are you in 4wd when it happens? More info is needed to help you with this problem.
BUBBA

 

Thanks for all the replies. Sorry about the lack of info. Its an automatic, and its happening in two-wheel drive (no snow or ice anymore up here in Buffalo, and its about time.) It happens definitely during coasting and when I'm driving at a steady speed. I haven't gone higher than 40 since I started hearing/feeling it yesterday. I'll probably crawl under there tonight and look around, maybe something will turn up.
Thanks guys