Poked around looking for an answer to this, my apoligies if it's a repost

Anyhow, truck background: '96 F250 XLT 4X4, 7.5L, IFS, new tranny (E4OD) at 100K, now up to 106K miles.. It's just recently began to shake/shimmy violently after hitting potholes, manhole covers, small bumps, uneven slip joints on the freeway etc., making me nearly come to a complete stop to get it to quit.

I suspected a tranny/motor mount was broken/unbolted, but everything appears to be ok under there.. nothing in the front end obviously out of whack..

Any ideas? It keeps getting worse, and the bumps that cause it just keep getting smaller and smaller heh

thanks in advance

Aerik

 

You have something worn in the front end. Check the track bar bushings. This should be a short bar coming from the cross member under the eng. to one side of the front end. If that is good then check all the rest of the front end, shocks, etc. Check the balance of the tires as well.

 

No track bar on that truck.


Get that front end checked out!!

 

maybe shocks?

 

I'd say ball joints or u-joints.

 

I had this exact problem with my 87 F250. It's the IFS. Put the FRAME on jack stands so the tires are a couple of inches off the ground. Have someone put a 2X4 under the tires one at a time and use it like a lever to move the wheel up and down. While he's doing that, crawl under and look at the suspension. On my truck the problem was the bracket between the passenger traction beam and the crossmember under the engine. There are 4 bolts holding the bracket to the crossmember. 1 bolt was completely missing, 1 had no nut, and the other 2 were loose as hell! Scary, considering I drove it like that 100 miles on the highway to get to my dad's garage so I could look at it. If I'd known it was that serious, I would have worked on it in the snow. Fix it! Don't drive like that!

 

Thanks for all the replies guys!

An update: (I hate when ppl dont get back and letcha know what the deal was)

Turns out it was the center pivot works for the IFS.. one bolt completely sheared off, 2 other bolts all bent to hell and about to drop out.. scary part was I used my truck to tow my 10K lb Weekend Warrior out into the woods and back, with my front suspension in that condition.. I suppose that woulda been quite the ride if it let go..

tough one to track down, as everything *looked* fine.. only after putting a wrench on misc. bolt heads did I figure it out..

a side note, if your truck is doing this shaking thing, keep it out of over drive because it seems to never happen when your foot's on the gas pedal, only happened while coasting/braking

Thanks again!

Aerik