Why is everyone against lift blocks?

I have noticed alot of people on here are against lift blocks for the rear. What is the reason behind them?
Just wondering what the negatives are, do they wear out the leafs faster? How would they wear them out?

I have a allpro standard leaf pack and wanted to add a 1" block to them but dont want to have problems or wear out my new leaf packs i just paid $400 for.

 

They extend the shock out so you dont have the travel you should. On road you are fine but off road you have the possibility of breaking the rear shocks. Plus its a stiffer ride.

 

On rare occasions then can actually come out. They also give the axle leverage to bend your leaf spring. This is sometimes refered too as axle wrap. A few years ago on another truck, I had a set of blocks in temporarily as I was having springs made and when I would pullout from a complete stop you could hear the rear spring snap back, from the block bending the spring upward. (Think of it as using a breaker bar on your ratchet to gain leverage) The block acts like the breaker bar. The bigger the block the more leverage you give the axle to bend the spring.

 

wait what?

they dont extend a shock any more than adding a taller leaf pack. its all the same in that regard, moves the shock eyes further apart

what blocks do is put increased leverage on the leaf pack, by moving it further away from the point of torque (the axle itself)

this increased leverage is what causes axle wrap (the axle twisting) and will wear out the leafs quicker.

is 1" a big deal for some added height? not really.

 

Oh look I was wrong. I swear that's what I read. But knowing myself I was surfing tw drunk again reading what ever. What you say makes more sense. My bad open sorry.




What the he'll was I reading? This is going to bother me now.

 

You might have been reading about spacer lifts.

 

That might be it. It was a while ago when I was new trying to figure all this out. Obviously still working on it. Haha

 

axle wrap axle wrap axle wrap. Like Mark said.

 

Rear blocks are fine, I cant see how they can cause axle wrap. I think its a internet myth.

Adding a small block doesnt change much in the geometry besides the drive shaft angle depending on how tall the blocks are .

Unless your a serious wheeler blocks are fine. I have add a leaf cause I didnt like the sag when weight is in the bed. The stock leafs are just to soft, I dont mind a harsher ride.

 

Because axle wrap sucks. Believe me, I am running blocks in the rear and I hate it. I was naive when I first put them on.

 

How do you know you have axle wrap ? Guys with out any lift complain about axle vibes ...

 

Any spring-under-axle design has axle wrap inherent in its physics. Adding a block increases the distance of the axle from the spring, increasing the leverage.

Go find some axle wrap videos and see how wit works under both acceleration and braking.

Edit: I meant spring-over-axle (SOA) in particular, but it's a leaf thing in general.

 

I think a 1" block is fairly harmless, like a 1" body lift (if done and maintained correctly). Once you starting getting higher than that for either one... that's when you're prone to more issues.

 

When you accelerate or decelerate, the axle will want to twist one way or the other. Blocks only add more leverage to their want to do this. This is why all the 12"+ lifted bro mobiles use blocks with control arms, their axles would probably fall off otherwise.

 

This is true for SOA and SUA. Agreed, it's physics.

 

After hearing that blocks could cause axle wrap, i took a video with a gopro and saw that I did have axle wrap. Plus the fact that they were 3" blocks does not help. I was able to counter the wrap with helper springs a bit, but just a bit.

 

The rear blocks causing axle wrap seems like common sense... The 1" block isn't a big deal but going higher is when axle wrap is more apparent and worn out leaves. I'm sure there are YouTube videos out there of blocks causing axle wrap. My dad has 2" blocks on his ranger that my brother and I installed because he wanted them. I had him watch the rear axle while I took off from a complete stop before and after the block install. He was surprised by how much the axle rotated and the leaves bent after the install.

To the OP... I wouldn't add a block to those new leaves. Recoup some of your money by selling them and get the expos if your wanting 1 more inch.

 

Meant to say SOA originally/especially. edited...

 

Putting on large tires, rockcrawling, and racing down trails can cause the rear springs to wear out prematurely and/or lead to breakage.

The point is that there's a scale and it's up to the user's preferences on what they want versus what they're willing to risk versus what options are there (particularly with avaliable $$). Extended shackles can also put a little extra wear on the springs but who knows how many tens of thousands of people do just that. It may not be the preferred method but for some people a 1" block should not be an automatic dealbreaker. That said, I'd never recommend anything larger than 1" for any Tacoma.