OEM Leaf Springs Torque

I have a 2008 PreRunner 4x2 with original leaf spring (no TSB). My leaf springs look more flat than arched. Is this normal? I do not have a pic at this time to post.

I have searched and can not find a definite answer to this question. I have found 37 FT LBS, 75 FT LBS, 80 FT LBS, etc.. Does someone have the official recommended u-bolt torquing?

 

Thanks for response, but does anyone have the official Toyota recommendations in print?

 

It's been discussed before that 37 ft/lbs of torque for the rear u bolts is actually wrong in the fsm. It's should be 73 ft / lbs. There is no way 37 ft / lbs would remotely be safe and enough torque for the rear suspension.

 

I set my wrench at 55Ft/LBS, and all bolts turned at least a whole turn before clicking. Could the loose u-bolts be the reason I have been feeling a lunge after coming to a stop sometimes?

 

Yes it could.

I would go ahead and crank them down to 73 Ft Lbs.

 

Hmmm. I've heard this being the cause before, but I sure don't remember it doing this until the past 6 months or so. I have had the truck since 2008.

 

http://www.suspensionspecialists.com/techinfo/Ubolt_Information.pdf