2006 Tundra RWD Towing Suspension Replacement Need Advice

Hey guys. Looking out for my old man. He used to be in the construction industry and recently switched over to doing local towing. His 06 RWD SR5 has just over 100k miles. He’s the second owner and looks like it came with some leveling kit. His leaf springs are practically shot.

Can you please recommend some stiff suspension and leaf springs for towing purposes? At this point the car is going to be driven until it needs a tow of its own lol.

Thanks in advance.

 

Junkyard leafs. Here in central Texas every tundra I see in a yard has front end damage with no bed or rear bumper and immaculate leafs. Maybe some shocks, rear axle, or entire suspension gone here or there, but usually vehicle is supported directly on frame and every time both leads remain.