i have a stock 97 250HD and am getting a 4" lift for it this summer, i have been reading what i can but still have a few questions that i hope somebody will answer. with 4" is it necessary to get sway bar drop brackets? the kit comes with blocks for the rear, can i take out the factory blocks and use factory springs with a shackle flip in the rear to achieve a level height, or would this put the rear higher than the front. also, there has been alot of discussion on the flips recently, but a few questions i couldn't find the answers to are: will the sky brackets mount to the existing holes in the frame, or will i have to relocate them? also, when you are talking about the correct pinion angle, what are you talking about, and how do you correct it or make sure it's right? thanx.

-jason

 

It depends on how tall your stock block is as to whether a shackle flip will put it when compared to stock. Say if your stock bock is 2'' and you remove it and flip the shackle you should gain roughly 3'' so then you would have 1'' of lift over stock. When flipping the shackle it will change your pinion angle as in rotating it up unless you drop the front bracket also. Dont know much about sky's product but have heard it is of pretty good quality...but why not just do it yourself?

 

the factory block is 2". so would the brackets that come with the lift fix the angle, or do they only accomadate the angle that is achieved with the blocks they supply? i really only need to get more flex in the back and replace the front springs, is there a better way to do that?

-jason

 

trac bars were designed to have a 0* angle (straight across) , but when you start adding lift and the trac bar starts to get an angle on it, it wont have quite the effect it was intended to have. what i'm getting at is, at 4" getting a drop mount isn't necessary and i prolly wouldn't worry about it but if you can get a drop mount or for whatever reason it isn't a big deal to get one its best to. also, everything i said about the trac bar also goes for the steering linkages... all angles should be as close to 0* as possible

the leveling issue you will just kinda have to play with it. go out and measure your shackle (from bolt to bolt) and it should be right at 3-3.5" long. thats how much lift you will get (assuming the angles are exactly the same as before). i would absolutely pull the blocks and then do the shackle flip to level it out. if need be make a longer set of shackles but make them from 1/2" bar stock so they are super strong!

yes the sky brackets bolt to the existing holes, i went that route and am very pleased. the only thing i didn't like was the shackle angle but i lived with it and it never caused any problems. its just not what i wanted.

its the yoke that comes out of the front & rear axle that your driveshaft bolts to. it needs to point directly at the t-case to that the u-joints aren't under a continuous bind. pinion angle needs to be 0* or very close to it!!! there are a couple of ways to deal with pinion angle. first is the easiest way which is to buy steel or aluminum wedges or shims. they bolt into your leaf pack and angle the pinion up. it works very well and is relatively cheap. you can also change the angle when you go and do the shackle flip. the more you move the shackle mount down the more the pinion angle points up. but that means drillin new holes. but its worth it after replacing joints 4 or 5 times!

-cutts-

 

you dont want your pinion at 0 degrees unless your running a cv shaft, or the other end is at zero degrees.

you want both ends at the same angle so the vibrations cancel themselves out, this will give you longer u joint life, and bearing life, etc. HAving them at signifigantly different angles will reduce u joint life and cause vibraiton...you want it like this if you dont have a cv http://www.pirate4x4.com/tech/billav...aft/degree.jpg

if you wanna learn more, go here http://www.pirate4x4.com/tech/billav...ft/index2.html

 

yea i think i forgot to throw that i there! that and i dont care on my rig... hmm maybe thats why i keep busting shafts!

-cutts-

 

so the shackle from bolt to bolt is 5", and if i remove the 2" block, that will give me 3" of lift with the flip? but with a 4" lift in the front that would make the front sit higher, would the only way to correct that be redrilling holes in the frame or an add a leaf in the rear?

-jason

 

an add a leaf would be easiest but it will help.

-cutts-

 

remember the rear of those trucks sit about 2" higher in the rear than in the front.

 

If you do go with the lift, i highly recommend the SUPERLIFT STEERING SYSTEM! It is expensive, but well worth the money! i recently installed one on my F350...and what a difference it makes

 

i just looked up the steering system, and i can't afford another $400 for that.

-jason

 

Maybe I'm just high on crack today but I've always been under the impression that on a regular driveshaft (non-CV) you have the option of either running both joints at the exact same angle OR running the pinion at 0*, you're just not supposed to have 2 different angles at the pinion and t-case (like 10* on one and 20* on the other). This is how my truck was setup before the lift and how I set it up after, never with any trouble. Typically most stock trucks have about a 0* pinion angle too. I know Billa Vista's site doesn't say this but I've read it on numberous sites and have run it/seen it run all the time.

 

so if you want both at the same angle, wouldn't drop brackets in the front create a different angle from the pinion in the rear?

-jason

 

Not understanding your question 100% Jason, are you talking about the front and rear axles?? Both pinions don't have to be at the same angle. We're talking about matching the pinion angle to the angle of the joint at the t-case. Is this making sense or am I totally off base as to your question?

 

ok, i was confused about that...but wouldn't the pinion angle and the angle at the t-case be the same angle no matter how much you lift it? it seems that geometrically those angles will always be the same??

-jason