Hi, im trying to find out what the stiffest shocks are I can install in the back of my TH wagon, thanks

You mean springs?

Most people recommend kings or dobinsons for springs.
For shock Kyb or boges I think.

Are you towing and need a stiffer shock?
From what I read on the forums here KYB seem to be stiff.
Either way I think you can likely get heavy duty shocks which would be stiffer than the normal ones

Hi, im trying to find out what the stiffest shocks are I can install in the back of my TH wagon, thanks

Why do you want the stiffest shocks? Load carrying? Towing? Handling?

By going too harsh with compression and rebound rates will make your wagon feel like a go kart, and will not improve ride or handling.

If your only putting hard shocks in the back and ignoring your front struts or the springs it will handle like a pig and be bloody dangerous.

Springs and shock absorbers need to work together.

If you really want to, I know King springs and I am sure others do custom spring rates. At requested height etc, such as you can get a custom made standard height Magna spring rated at say 300-500lbs if you really wanted to, which is a lot stiffer than standard and the lowered springs are around 180lbs I think.

Koni reds.