Hey guys, I've been noticing a weird vibration at higher speed. Usually starts at about 45mph, I've noticed it would not occur after like 55mph. I'm not really sure how to explain it but it almost feels like pulsates. (like hum...hum...hum..hum, if that makes sense). The pedal is sensitive enough where I can feel it almost vibrating up it. But it also seems like its coming from the transfer case area. Any thoughts?

 

I just had the same thing in my f-150 probably a bad u-joint.

 

Driveshaft u-joint?

 

Yeah.. If you have the time. I would replace them on both the back and front driveline

 

Might also do a visual inspection on all the tires. Sounds alot like a broken belt.

 

Check your u joints ASAP! I waited a day too long, one broke, and it wrecked my driveshaft, and I had to buy a new one.

 

I agree. I had that happen twice before. Once was on prom night. My old bronco 2 decided to spit out it's drive line while we were all dressed up lol.

The other time was in my 79 f-150 both times once it started vibrating at about 45mph and a few miles down the road the drive lines dropped. So as soon as I noticed it I'm my 94 I replaced them. Its really easy to do and good preventative maintenance. So if you aren't sure do it anyway.

Another quick tip. Try throwing aboit 300lbs in the back of it and see if the vibrations stop it may be just enough weight to change your driveline angle and if it stops or lightens up the vibrations it definitely is a bad ujoint

 

Yeah I believe it may be U-Joint. I'm sure they are the original 20 year old joints. Alot of the work I've done on it has been replacing 20 year old parts. Give props though that's a lot of abuse.

@Gator the tires are actually pretty much brand new, maybe only 10k miles on them

 

My '94 F150 had a strange vibration similar to that, I don't know what trans you have but I went up the driveline with new u-joints, new slip yoke and tail shaft busning and it showed up a few months later, E4OD trans gave up the ghost on way to work.