3rd Gen leaf spring question

Is it possible to permanently tweak the rear leaf springs on a 3rd gen TRD Sport?

My rear leaf springs (mostly the bottom leaf) have a slight downward bend when the truck is unloaded, is that normal? Or should the springs all have an upward bend when unloaded?

I just installed Sumo springs on Saturday to help support when towing my small camper (I use a weight-distributing hitch), and there is supposed to be a fair gap above the Sumos when unloaded. I have almost no gap when unloaded, and when looking at things I noticed the slight downward curve of the springs.

I don’t think I’ve ever really exceeded the payload on the truck. The only real possibility was a trip from WI to CO and back with two dirt bikes in the bed (550lbs total) and probably another 450 lbs of people and gear in the cab, so 1000lb total payload, about 100lb over. That is a long way to haul with the weight of the bikes in the back, and I know we hit the bump stops pretty hard (before I had the Sumos) a few times on the highway. Would that be enough to permanently tweak the leaf springs?

 

The factory springs are very soft, and sag quickly with any actual hauling(like you’ve done with dirt bikes and people). “Add a Leaf” helps, but those wear/sag with time as well(usually 1-2 years). I doubt it tweaked them, likely they are just losing the arc. Id suggest upgraded springs, it’ll make the truck feel more planted and will tow 10X better than stock. Another option is to add airbags in the rear for use when towing(i run Firestone RideRite bags)

 

Yes, the bottom (overload spring) will curl down.
If you aren't lifted, or bought the sumo spring for lifted trucks, there might not be a gap.

 

Leaf springs can technically be re-arched but it is not recommended. I don’t even know if you could find a shop that would do it anymore either.
Best bet is to replace the pack, that’s what I’m doing this coming weekend. I got a set of Icon RXT for my truck because it was getting too saggy also.

 

are you saying it's normal that the bottom leaf is curled down a bit, or that they will do that if they are overloaded?

I did get the 612 Sumo, which is the newer version for stock Tacomas that is supposed to give a gap before it hits. Since mine has little to no gap, I was wondering if something was tweaked.

 

Normal
And gap or no gap I think they'll still do their job.

 

Yup, I think I like the Sumos for what they will do while loaded, it's just very noticeably stiffer hitting the Sumos while unloaded. I was hoping the gap that should be there during normal unloaded road driving would keep the ride the same. But I guess even normal road driving can cause well over an inch or two of suspension travel, so maybe I just need to get used to it.

The Sumos thread onto a stud welded to the new base bracket. I was thinking of buying or making some hard rubber bump stops I can install when not towing/loaded and just put the Sumos in place when I need them.

 

I tried a lot of cheaper solutions. The only real thing that worked for me was to buy a whole new leaf pack. Check out dobinsons leaf packs. They're underrated

 

He's saying it's normal. The bottom leaf is called the overload. It is a last support for an occasional overload condition.

 

Are there good (helper) springs out there for our trucks?

 

Roadmaster active suspension is truly a great "helper spring" i've had it for 173'000kms and even when I broke one their customer service was easy to work with, great and sent me a whole new upgraded kit for free to replace them both.

 

I had a set on a GMC for years without problems. Gave noticeably better load carrying and light trailer balance.

 

whole leaf pack is the way to go on these trucks for truck stuff

 

I added Sumos for hauling my small trailer as well. Same as you, there is almost no gap between them and the frame. You can definitely feel the Sumos on certain bumps when unloaded, but I’ve gotten used to it. They work really well at keeping the load from sagging the backend. Giving up a little ride comfort is worth it to me. My bottom leaf is also turned downward. Normal.