Shock/Suspension Question: Thumps on bumps

I have put 180 lbs of sand bags into my bed for better control during the winter driving season. I have all original shock/suspension equipment on my 2005 4x4 TRD with 176K miles.

I have noticed when I go over any sort of road bump, dip, etc that I get a heavy thump in the bed like it is bottoming out. I did a bumper shake test on all 4 corners and did not notice any excessive movement. When the weight is not in the bed, I don't bottom out.

I need the weight for control but hate the thump on bumps.

Any suggestions on how to correct? Should I get new shocks, etc?

Thanks for any and all suggestions.

 

New leafs, add-a-leaf kit or better bump stops (I've heard timbrens are good if you're going to go that route). Those are probably your best options. There are others like airbags but I don't think that'd be a good idea to correct the problem you're having.

 

Thanks guys! I'll look into this.