2005+ Toyota Tacoma Rear Spring Under Kit

2005+ Toyota Tacoma Rear Spring Under Kit

  • 3 Items
Part #: tt056lsuk1

Regular price $2,395.99 Sale

https://cdn.shopify.com/s/files/1/1682/0939/files/TacomaSUAInstall_PDF.pdf?v=1658349616Now available for the 2005+ Toyota Tacoma is our bolt on spring under suspension kit with up to 19" of wheel travel!

There is no question that the rear suspension on the Tacoma leaves A LOT to be desired.  Upgrading to a replacement spring pack will produce a very marginal improvement in performance and is extremely underwhelming.  There are two main issues with the Tacoma rear suspension from the factory.  The first being that the trucks come with a "spring over" design from the factory meaning the leaf springs are mounted to the top of the axle.  Due to this design the spring pack must be relatively flat to prevent the truck from sitting way up in the air.  Because the spring pack is almost flat at ride height you are forced to limit the amount of up travel available to prevent the springs from going into a negative arch.  Your average Tacoma is only able to achieve around 4-5" of up travel at ride height and this is what makes for a very harsh ride off road.  Up travel is the most important component of a rear suspension design because its what allows the rear of the truck to carry through bumps.  Without the necessary up travel the rear will constantly be slamming the bump stops which in turn causes the rear of the truck to "buck". 

The second issue is the way Toyota mounted the rear shackles.  From the factory the shackles come inverted meaning they are pointing up.  Inverted shackles do not allow the springs to move in their natural arc which creates a harshness in the springs as they flex.  Also, because the rear of the Tacoma frame is wedged out towards the back you cant simply just flip the shackle to the correct orientation without adding significant lift to the truck.  The old way of thinking is to build drop down shackle mounts and run a taller inverted shackle.  While the taller inverted shackle helps it still doesn't allow the springs to move in their natural arc.  You also end up with big "boat anchors" hanging off the back of the frame which put a ton of leverage on the frame as well as get hung up on rock.

When we designed our new kit we took all these design flaws into consideration.  The first thing we did was start with a completely new custom spring pack from Deaver Springs.  The new spring pack is much longer than the factory pack and has a significant amount of arch built in.  Because the springs have so much more arch we are able to move them to the underside of the axle in whats referred to as a "spring under axle" or SUA set up.  By moving to a SUA design the axle is now able to completely bottom out on the frame.  This results in over 5" of additional up travel at ride height, allowing the truck to have 9-10" of up travel while maintain a stock ride height. 

Next we addressed the inverted shackle problem.  We designed our kit to follow the wedge in the stock frame.  This allows us to place the rear shackle outboard of the frame and flip it to the correct orientation.  Because the shackle mount is outboard of the frame we are able to move the shackle pivot up to the side of the frame.  This takes all the leverage off the rear of the frame and also allows for the use of a 7" or 9" shackle without effecting the ride height.  We also gave the rear shackle mount a ton of adjustment so you can fine tune ride height and the spring rate curve depending on your vehicle weight.  And of course this completely eliminates the "boat anchors" on the rear of the frame.  By keeping everything tucked up nice and tight you will no longer be getting hung up on obstacles.  

We also did a couple other neat things... In order to eliminate the typical squeaky rear bushings commonly found on most shackles we went to a double uniball design.  For the lower spring plates we went with a cradle design that's made out of 1/4" cromoly plate.  The cradle design allows the U bolts to be shorter than the spring pack so nothing is hanging down below the springs, this maximizing ground clearance.  

Our front and rear spring hangers are also 100% bolt on.  Simply remove the factory spring hangers and the new hangers bolt right into the existing holes!  You will need to weld on new lower spring perches due to the SUA design which mounts the springs underneath the axle.  

The complete kit includes Deaver H70 springs, front/rear spring hangers, uniball shackles, spring perches, spring plates, u bolts, spring bushings, brake lines, bump stops and all necessary hardware for the installation.  For trucks on the heavier side you have the option of going with the H70HD spring pack.  The standard pack works best for trucks that only run one spare tire in the back, light rear bumper and limited accessories- anything more than that and the H70HD's will be ideal.  The spring hangers, shackles, and spring plates all come powder coated black.

This kit cycles 17" of travel and up to 19" of travel with a frame notch.  For shocks we recommend using a 14" travel 2.5" free bleed that is designed around our weld in shock mount kit.  You can also run 16" shocks with a custom bed cage.  We strongly recommend against using hydro bump stops in the rear as they cause the rear of the truck to "buck".  We prefer using the low profile energy suspension bump stops and modifying them to fit.

The SUA kit works with both second and thrid generation Tacoma's as well as short and long bed models.

Welding, drilling and basic hand tools are required for installation