Are all 2gen rear ends set up like this?

So today I replaced the front pads and rotated the tires. I had noticed the rear tires wearing oddly un normal. Air pressure is good in all tires.

Left tire was on the Rear. Right tire was on the front. Both sides Looked like this. Front and Rear. Usually the front would have West issues.


So with the rear tires off I looked at the axle. Checked the flanges for stress, axle looked straight but then I went to the rear of the Tundra and noticed the mounting of the leaf springs looked odd to me.


Then from looking directly above it was even more evident. (Drivers Side)


Why are the leafs not parallel to the axle flange or perpendicular 90 to the axle? Is this manufactured like this?

I measured the leafs directly across from each other.
Driver Rear to Passenger Rear = 40"
Driver Front to Passenger Front = 49"

In all my trucks. My builds. All leaf sprung systems are parallel. Not trapezoid. WHAT GIVES?! Is this causing stress on the axle and making my tires wear bad?

Would be nice for a suspension builder to chime in on my finding. Unless this is normal and my tires are wearing odd because of shocks.

UPDATE:​

Actual Picture of the under belly of a 3rd Gen Tundra.



As Wynned found out, Yes the rear leafs are set up not parallel with the frame or parallel with tires like any other leaf sprung truck on the market. It's sole design is to act like a track bar that you would see in Coil sprung suspension or linked vehicles. The leafs are more of a trapezoidal design if you were to look it at from the bellyside. The following is a great description of this....

Tundra Frame and Suspension Design
• Design strategy behind the Tundra frame and suspension
• Features and construction elements of Tundra chassis
• Benefits of Toyota's sophisticated engineering

A pickup truck's frame and suspension designs are key indicators of a vehicle's strength and poise. Chassis dynamics are often more complicated for pickups because of the extraordinary demands of hauling heavy loads and possible off-road use while still meeting Toyota's rigorous safety standards set for the entire lineup. The trend toward larger cabs also means the truck must provide a comfortable ride for the passengers.

The ladder frame is the truck's backbone, and although simple in appearance, its function is too complex to be narrowed down to a single approach. The competition brags that the frames on their ½-pickups are all fully boxed, which provides more "stiffness." But stiffness does not equate to strength. Frame strength is a combination of factors, including crossmember design and manufacturing choices. Toyota considered many factors when engineering the TripleTech™ frame.

TripleTech™ Engineering

A single method of frame construction isn't necessarily the best solution when designing a truck because some priorities may be compromised. Toyota's approach capitalizes on the benefits of three proven construction methods to deliver a frame that offers load-carrying capability, crash performance and ride quality. Here's how:

• The front section is fully boxed to support the engine weight. A robust front end also offers impact protection and provides solid mounting points for the steering and suspension components. This, in turn, improves handling response and steering precision.

• The middle section under the cab is a rolled-lip C-channel reinforced with heavy gauge steel. This design is lighter than fully boxed but still offers impact protection.

• The rear section under the bed is open C-channel—the same design used on most heavy-duty pickups for the entire frame. The open design offers a small measure of compliance under heavy load to help absorb road impacts before reaching the passenger cab.


Tundra suspension design
Toyota relies on refined proven and cost-efficient designs for the front and rear suspensions.

• Front is independent, double-wishbone with coil-over shocks. This arrangement provides consistent linear spring action when compared to some competitive models that mount the coil spring and shock absorber separately to the lower control arm.

• Rear is a traditional leaf-spring/live-axle arrangement. Leaf springs locate the axle and help control body sway. Trucks with a coil-spring rear suspension require an anti-sway bar. Toyota engineers also mounted the leaf springs in a "trapezoidal" pattern, meaning the front mounting points are wider than the rear shackles. This "towed out" design is very effective at reducing lateral axle movement and helps improve tracking when towing.

• Rear suspension features staggered shock absorbers to help reduce wheel hop under hard acceleration

If you liked this article you may enjoy this one too! http://jimmcnatttoyota.blogspot.com/2008/12/tundra-tripletech-frame-explained.html

 

The leafs aren't perfectly parallel to the axel. Looks like this -\ instead of -|

 

Very very slightly. One has 7-8 threads showing, the other has 6.

 

Yes. I agree I need to get rid of the blocks. It's on my list to do. I bought this Tundra with the 6"FABTECH lift. I'll be redoing the rear end this summer the correct way. I've been looking at a few different set ups plus air bags because I tow.

As far as the way these leafs are from Toyota, I've just never seen such design. Made me question what's happening with the rear tires.

I've had a friend follow me on the street and freeway and the truck doesn't crab walk or anything.

 

Rear is a traditional leaf-spring/live-axle arrangement. Leaf springs locate the axle and help control body sway. Trucks with a coil-spring rear suspension require an anti-sway bar. Toyota engineers also mounted the leaf springs in a "trapezoidal" pattern, meaning the front mounting points are wider than the rear shackles. This "towed out" design is very effective at reducing lateral axle movement and helps improve tracking when towing.

-https://jimmcnatttoyota.blogspot.com/2010/03/tundra-frame-and-suspension-design.html

I found this tidbit.

 

Sumavabitch! I had a small feeling this may have been their design. That answered my Original Question. Now I need to fix my Tire wearing issues. Correct the suspension, ditch the blocks.

 

sounds like a plan

 

How about take off both of your rear wheels and take a straight edge to each side, measure top and bottom from drivers side to passenger side to see if your axle is bent up or bowed or something like that?

 

IMO you need new shocks. They are either shot or poorly valves for your spring rate.

The blocks only compound this.

 

Why would this cause inner tire wear? I can understand shocks could cause it to make the tires wear cupping or chopped out but not just inner tire wear. At least that's how I'm reading the pictures he posted. To me it looks like a bent axle or housing would cause that.

 

@GNTundra so are you saying that the outer edge of the U bolts are possibly too tight causing the axle to bow causing uneven tire wear?

Edit: let me rephrase that not over tighten it but tightened unevenly?

 

Well the way I see the tire, it looks like the one on the left is wedged and worn more on the inside. The front looks normal. I'm on an iPhone 6 too. Maybe I'm just assuming too much. I didn't know you could really align the rear end other than making sure everything is bolted up properly. New to me. I thought it was all factory set from where the leaf springs bolts on to the frame and the leaf springs to the rear end.

 

Both rear tires are worn in center. The tread blocks also are cupped a bit, facing backyards. I have never seen any of my past trucks that the tread would cup backwards. Even my 39" Super Swampers Boggers would cup slightly forward.

 

As far as blocks go. I agree. I will be ditching them. I wheel my Tundra a lot and I know the issues that comes with blocks.... I've had a 97 F-350 with 44" Tires on 4" rear blocks and re arched springs that have never had this type of tire wear.

I will take a torque wrench the U-Bolts soon as I get some time. My other guess is that 116,000 miles later, maybe the bushings in the shackles need to be replaced. Including new shocks and if I'm going to do all that work, I'll just redo it all with proper springs.

EDIT: I'm no stranger to lift block failures. This is what happens when blocks snap in half while mudding. This is my 72 Scout II, happened 11 years ago.

 

we've been scienced

 

So question, If he gets rid of the block, would he just have to replace the space with the correct amount of leafs?

 

I've seen the block itself give out too. Either is a disaster and inevitably destroys far more expensive parts in it's wake.

 

Or springs with more arch to them.

 

gotcha, because I want to get rid of the block in the rear and wasn't sure. I'm no guru, I just break it once it's installed lol

 

That's how many of us learn what works and what doesn't. Also, just adding three inches worth of leafs would result in a spring pack that would be so stiff as to probably be intolerable to drive.

 

makes sense. any recommendations?

 

Correct.
Most likely a combination of slightly longer hangers and arched springs.

I have been looking at this set-up. I will be contacting SDHQ before my trip to Tundras to Sedona
http://store.sdhqoffroad.com/07currentrearleafspringexpansionpack.aspx

 

I'd see what Deaver or Alcan have to offer myself. I'm sure that there are other suggestions too.

 

Just imagine how these felt on the ole caboose.

 

Hahahaha it took me 3 damn hours to get that bad boy off. It sucked. I've cleaned her up and waxed her and now I'm waiting on my part from toyota so I can drive again. Fucking firestone did an alignment and didn't put the lower control arms nuts back on, so it's sidelined until I get them and have it aligned AGAIN.

 

I

In my defense, the road took a day off and decided to drop off and whalah.

 

Ouch. Talk about a stiff ride.