Ok so I lifted the 450 finally. Its a 4.5 inch Icon with with 5 inch blocks in the back. I took it for its first ride last night and not even getting into it and I can feel the axle moving. So who makes custom ladder bars? Also keep in mind its a 450 so it has a square axle in the back instead of the normal round one.
Thanks
Nick

 

Call up Farmboy fab... they should be able to make you something.

 

In drag racing you don't use ladder bars and leaf springs because the leaf moves vertically, and the ladder bar moves in an arc, thus causing a bind. It only stands to reason that the same physics would apply to trucks with ladder bars and leaf springs. Sure it will eliminate axle wrap, but it will limit suspension travel, too.

Blocks act like a torque arm between the axle and the leaf spring. The bigger the block, the bigger the torque multiplication. They aren't bad, but all things within reason. 20 years ago, more than 4 inches and/or stacked blocks were strict tabboo. Now lifts use stacked blocks up to 6 inches. Ever seen stacked blocks spit themselves out? It's pretty ugly.

Ditch the blocks for a spring lift and/or a relocated hanger/shackle out back. If not that, do an add-a-leaf to reduce the overall amount of block used. My 250 was an axle hopping PIG at truck pulls with 5" blocks. My budd's 03 F350 with taller blocks would wrap the leafs into an "S". With the 6 inch Pro-Comp springs it truck pulls better. Personally, I feel it pulls my 18' flatdeck car trailer better with the spring lift, too.

 

I'm not following your ladder bar and leaf springs idea there. Traction bars, that I see most guys using (the inexpensive route) are the ones that will cause binding. You are right, the leaf springs will move into an "S" shape. All it's doing is twisting the axle and binding the leaf springs. You want to stop the axle from twisting. Ladder bars are perfect for this. They mount in two locations on the axle housing (one on top and one on bottom usually) then they are mounted to a hanger up front. The hanger is the important part. You can use single bars like the inexpensive traction bars that I see so many people using (not sure why...), but the key is to have the hanger up front, like a leaf spring hanger so it can move forward and back. The solid mount ones I see can cause binding. The axle itself moves in an arc when you stomp on the skinny pedal, which is axle wrap, this is what we're trying to prevent. Karls03, this sounds like what you're saying about the drag racing. If the ladder bar was built on a hanger system, then there would be no binding moving forward or back, it's strictly to limit the axle wrap.

I agree, springs are better than blocks though.

Anyone here ever watch the vids that tanks250 has posted up all over the powerstroke forums with his axle wrap pre and post ladder bars? Pretty cool stuff.

 

Axle wrap is the product of all that torque being put down. At a certain point, the pinion climbs the ring gear pulling the pinion up and putting an S in the leafs. Tall blocks will only increase this effect.

When the axle goes up or down, ie suspension travel, it is more or less vertical. That's the purpose of the shackle movement.

When ladder bars move, they move in an arc. It's a straight bar, it HAS to travel in an arc. Ever notice how coil-spring rock crawler rear axles seem to move forward in full droop? For a full illustration, watch Stacy David of Gearz on Speed Channel put ladder bars on a leaf spring truck. A floater housing was used to allow the fore and aft movement required by the ladder bars. In short, the leaf springs were there for suspension only in place of a set of coil over shocks.

I'm certain that the videos mentioned eliminated axle wrap, but they also limited axle travel. My truck was limited by the front sway bar on that RTI ramp pic I posted. Put on rear ladder bars and it would not have gone that far.

So, if you're going to be a concrete 4x4, by all means do some bolt on ladder bars. If you intend to do any kind of 4 wheelin (like I do), remove them before you leave the tarmac.

 

Ok, we're on the same page, but thanks for the explanation and clarification, I never even thought about big 4x4's. I just had my mind on a track truck for some reason. Tank runs 4.5" lift with 41" iroks on his truck, I'll get the vid links. I'm not sure what route he ended up going.

The solid mount traction bars I see everywhere are even WORSE though, since they will technically start binding with any up or down axle movement.


Here's tanks250's vids of BEFORE traction bars:


AFTER traction bars:



The before vid, is even worse than it looks.