Help trouble shooting shimmy

[Derrick Willis]

I finally have my cruiser back on the road after rebuilding transger case and installing H55F. I installaed 31 inch tires on it. When driving on the highway it runs very smooth at speed, but if I hit a bump, it will start to shimmy. Looking underneath, everything appears tight. I will replace the steering stabilizer. Any ideas on what else I can do to troubleshoot?
thanks

 

[riverliver]

Balance, or re-balance the tires.....

 

[Derrick Willis]

Balance, or re-balance the tires.....

I will have them rebalanced, since the truck does not shimmy on smooth roads, I thought it might be something else.

 

[High Desert]

that sounds like worn tie rod ends and/or worn stabilizer. Jack up the front end and grab the tire/wheel and shake it around (both front wheels off the ground)
Poor mans check for worn loose parts. If it has never had a steering stabilizer replaced that could be the culprit there. Only test I know for that is to take a end loose, (not easy) and pump it to see if it resist or if it does not.