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Discussion Starter · #1 ·
So I have my track bar set to 39 1/8th when. I had my 2in Thuren coils. This is supposedly a good setting for carli 3in coils as well.

The axle is still off to the drivers side. What is the best most accurate way to measure/set this??
 

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It's not really important that it is perfect other than for visual purposes. I would undo it at the axle end, adjust it 1/8" at a time until it looks right. You can always measure with a tape measure between frame and inner edge of tire on each side, subtract the passenger measurement from the driver's side, divide that number by 2, then adjust the track bar out by that number plus a hair more to take into accound the angle. Good luck!
 

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Discussion Starter · #3 ·
My OCD makes it really important......lol
 
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I used a 4' level on the tires and measured the distance to the fender. I'm going to guess that the bar needs to be 39" with a 2" lift. My driver side looks like it's out farther but both sides are 1 1/4".
 

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Discussion Starter · #5 ·
From my quick eyeballing it looks to be about an inch off to the drivers side. I think I'm going to shoot for 39 5/8th for the length. I am going to measure on Wednesday and see if my measurements are close.
 

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everyone says 39 1/8", any longer and the coil will hit the track bar bracket. but with that measurement on my truck, the axle is pulled way to the driver side.

i am at about 39 1/2" and my axle is nearly perfect. my coil is nowhere close to touching the track bar bracket.

I'm starting to wonder if 39 1/8" is good for previous gen trucks, but not 4th gen. :confused013: There have been several little, yet significant differences discovered on the 4th gen trucks. For example, the need to run a spacer on the frame side track bar mount when using an aftermarket track bar, and the whole front driveshaft issue...
 

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Discussion Starter · #7 ·
What is the spacer in the aftermarket track bar you mentioned?
 

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What is the spacer in the aftermarket track bar you mentioned?
carli supplies a stainless steel shim with their track bars. it is to be used on 4th gen trucks. I think it is about 1/8th inch thick
:thumbsup:
 

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Discussion Starter · #9 ·
Interesting..... My Thuren does not have one.
 

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Discussion Starter · #10 ·
39 5/8th and it is perfect.

Another thing off my OCD list
 
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39 5/8th and it is perfect.

Another thing off my OCD list

:thumbsup: take a look at your driver side coil and coil bucket. are they anywhere close to coming in contact with the track bar bracket? thanks
 
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Discussion Starter · #12 ·
:thumbsup: take a look at your driver side coil and coil bucket. are they anywhere close to coming in contact with the track bar bracket? thanks
Probably 1.5 - 2 inches of clearance dont have a tape meaure handy but i dont see any way i can compress the front suspension with my driving habits enough to make it hit.
 

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What looks like enough clearance at ride height, may not be so at full suspension compression. The axle drastically swings to the passenger side upon suspension compression and the contact will only happen close to full compression. The only real way to tell if its going to hit, without going out and hitting some big bumps, would be to: Put your truck on frame stands, pull your coils out, hook everything back up and cycle your suspension to full compression with a floor jack to see if anything is going to make contact. I will pretty much guarantee you that any measurement over 39-1/4" will make for steel on steel contact :D
 

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Discussion Starter · #14 ·
What looks like enough clearance at ride height, may not be so at full suspension compression. The axle drastically swings to the passenger side upon suspension compression and the contact will only happen close to full compression. The only real way to tell if its going to hit, without going out and hitting some big bumps, would be to: Put your truck on frame stands, pull your coils out, hook everything back up and cycle your suspension to full compression with a floor jack to see if anything is going to make contact. I will pretty much guarantee you that any measurement over 39-1/4" will make for steel on steel contact :D
Im sure it would but the most action my rig sees is the speed bump in my work parking lot and that is taken at 10mph tops.
 

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Im sure it would but the most action my rig sees is the speed bump in my work parking lot and that is taken at 10mph tops.
You might be surprised how much the suspension cyles just going through a big dip at an intersection at speed.:S:
 

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How is recentering the axle after a small lift any different than having the axle centered from the factory with all factory parts?:confused013:

I don't understand, the axle is centered from the factory and the coil/bucket doesn't hit the track bar bracket...

I'm confused, guess I don't understand the physics/geometry. please enlighten me....
 

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Discussion Starter · #17 ·
How is recentering the axle after a small lift any different than having the axle centered from the factory with all factory parts?:confused013:

I don't understand, the axle is centered from the factory and the coil/bucket doesn't hit the track bar bracket...

I'm confused, guess I don't understand the physics/geometry. please enlighten me....
Only thing i could think would be the bumpstops preventing too much uptravel......
 

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How is recentering the axle after a small lift any different than having the axle centered from the factory with all factory parts?:confused013:

I don't understand, the axle is centered from the factory and the coil/bucket doesn't hit the track bar bracket...

I'm confused, guess I don't understand the physics/geometry. please enlighten me....
If you adjust your ride height by 3" and lengthen your track bar by 1", but keep the bump stops at the same height, when your suspension compresses; It takes the trackbar from being on and angle and makes it horizontal. In turn, your entire front axle will be sitting 1" farther towards the passenger side than it would be with stock suspension/tracbar. Your axle does not move straight up and down during suspension cycle, but shifts from side to side (moves to the passenger side upon compression and towards the drivers side upon extension). This is all due to the fact that your track bar is on an angle!! Clear as mud? :D
 

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I have mine at 39 5/8 also and axle is dead center. I have bottomed out my suspension and my track bar clears the spring bucket.
 
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