According to my NON-Scientific testings, TRD springs have lost about 20% of their rate after two ventures off-road...
There have been numerous bottom-outs, full extensions, and everything in between during last two excursions. TRD provided smoother ride on gravel, but were completely overwhelmed by high speed off-camber driving, bottoming out more times than I wanted. Stock springs, I remember, performed well in off-camber situations, but completely rattled my teeth on gravel.
TRD springs are defenately hold their worth on road, but off-road they fall face down ...
So, Im getting meself some Megan springs with better struts/shocks(koni), with some spacers, I should be able to re-gain rediculous drop they offer.
Will see how they perform. 280/230LB/in vs 160/150Lb/in coils might just work.
I am ready for some serious teeth rattling...

There is never an end to tuning/modifications.

 

Why would anyone want lowering springs for off road driving?

 

Why would we want springs at all?

 

because bags are for groceries?

 

If anything you would want more height for off road driving.

 

Not necessary, look at WRC, they have height limits, yet they jump and drive like MAD...
Its all about right combo...
I'll find one, just I need time...