I had to make a sudden stop this morning on the way to work and now my truck is shaking pretty strong. Its not just when stopping though. Its even doing it when I first put it in gear when starting it up. Then while driving at slow speeds it seems to be pretty much anytime I give it gas. Doesn't seem to do it just coasting. It had new pads/rotors about 1k miles ago. Truck is an 88 f150 4wd 302 automatic. Any ideas?

 

Forgot to mention it idles fine in park and neutral

 

An update. I crawled under the truck while someone held it in gear running and couldn't notice anything wrong. It is doing accelerating and coasting at slow speeds. It seems to go away at higher speeds. Also while slowing at a stoplight today I slid it into neutral and it went away so wouldn't think its tires brakes etc. Has to be in engine or driveline. Any ideas?

 

Does anyone think this could be a motor mount? I tried looking at them anddoing the brake torque check but didnt see much movement. This is the main thing i can think of though.

 

Since you say it was hard braking which started the issue, why not checking the brakes? it's the logical step... Since you say it now does at all times i would check if any part of them became loose and is causing trouble.

 

sounds like a possible cylinder misfire to me. at first i said warped front rotors but now that you say its giving you problems when idling and accelerating in gear, i would say cylinder misfire. look for a vacuum leak/do a fuel system clean. check sparkplugs and sparkplug wires too. may need a replace. my '66 mustang was having a lot of trouble too, like yours. did a tune up and it went away.