Thanks man, that's good news. That's a great write up. Now I'm getting motivated to rotate the knuckles and have it right.
I can't wait to spend 4 hours grinding the welds off.
Dana 30 Caster Correction
- Thread starter kkemp
- Start date
Thanks man, that's good news. That's a great write up. Now I'm getting motivated to rotate the knuckles and have it right.
I can't wait to spend 4 hours grinding the welds off.
While reading this thread, I can't help but think that if you got vibrations in the front with a 4" lift, your problems might lie elsewhere. Are your tie rods in good shape? Your unit bearings still tight? Your pinion bearing solid? Your t-case output intact? I ran my D30 for years with 4.5" of lift and left the castor where ever it ended up and never had a problem. I understand every jeep if different, but it'd be a major smack to the forehead to find out you did all that work when all you had to do was replace a unit bearing.
I have to agree with Devin on this. On my YJ I have SOA with 2" lift springs in the front and no caster correction. Not even a cardan style drive shaft, and no problems with vibration. I even just had to replace a terrible tie rod end and unit bearing, and even with those shot, there still wasn't too much vibration.
waynehartwig
www.jeeperman.com
- Location
- Mead, WA
...And I had a 6" lift on my TJ with no vibrations. Granted, my caster wasn't 7*, it was probably more like 10*.
But the problem is I know Kevin had the entire front end rebuilt in 8/06 - that's gears, locker, ball joints, shafts w/disco eliminator and unit bearings. I did that when I rebuilt the D44 rear that I swapped in.
I'm not sure why this is so confusing. From the perspective of the drive shafts there is a 5 1/2 inch lift. That's because I have a 4 inch spring lift PLUS a belly up skid plate which raises the transfer case another 1 1/2 inches. As it's set up right now, there is NO vibration. Only the caster is off. It's currently at +2 degrees. I've only driven it once like this. I didn't notice any problems except the steering wheel doesn't return to center if you let go of the steering wheel after turning.
OK, I think I know why everyone is confused. A couple years ago I installed a double cardon driveshaft in the front. It made sense at the time. I had Wayne remove the disco front axle shafts and install solid axles. After that I had tons of vibration. The driveshaft was worn out and sloppy anyway, so I got a new one. Based on the angle of my pinion, the CV shaft was a perfect match. It worked great till I lifted it again. The fact is, if I didn't have a CV shaft, my pinion would not have to be tilted up as high as it is. Everything would have probably just worked out. Maybe a little adjustment would have been needed but not as much as I need now with the CV shaft. So, my choices are, get a new non-CV shaft, or fix the caster. As I see it, it's kinda sixes. I actually prefer having the CV shaft and fixing the caster. So the main difference in my case is that CV driveshaft. At least that's my take on it.
OK, I think I know why everyone is confused. A couple years ago I installed a double cardon driveshaft in the front. It made sense at the time. I had Wayne remove the disco front axle shafts and install solid axles. After that I had tons of vibration. The driveshaft was worn out and sloppy anyway, so I got a new one. Based on the angle of my pinion, the CV shaft was a perfect match. It worked great till I lifted it again. The fact is, if I didn't have a CV shaft, my pinion would not have to be tilted up as high as it is. Everything would have probably just worked out. Maybe a little adjustment would have been needed but not as much as I need now with the CV shaft. So, my choices are, get a new non-CV shaft, or fix the caster. As I see it, it's kinda sixes. I actually prefer having the CV shaft and fixing the caster. So the main difference in my case is that CV driveshaft. At least that's my take on it.
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This is where the vibration confusion is coming in. Really, we are just trying to save you some time and money, since none of the rest of us have found it necessary to do any knuckle rotation. It sounds like you had your mind made up though before you posted the original question (like most posts on this forum). I like the ambition, and good luck with the project. I am curious to hear about the outcome.
I finally got this project done tonight. Wow! what a lot of work. Anyway, I took the Jeep out for a test drive on Wasatch Blvd and I-215 to see how it does. Amazingly, enough everything was just perfect. No steering problems and no vibrations.
So, probably the biggest and hardest part of this project was rotating the steering knuckles. It took a whole weekend of grinding to bust them puppies loose. I initially rotated the first knuckle 5 degrees since that's what it seemed to need. The next day after I got the second knuckle done, I rotated it five degrees and then compared it to the other one. Whoa! there was something wrong here. They were not even close to the same. I was under the impression they were the same. Anyway, at that point I just blew it off. It was my understand that it was very important for both knuckles to be extremely close. So that's what I did. I set them both for 7 degrees using a straight edge, a tape measure and a little trig on the calculator to set the angle on the knuckles while the axle was mounted up. I figured out pretty quickly that my welding skills were not up to the task of welding the knuckles back on so I got in touch the UNSTUCK (Josh) at the Rad Jeeper and got him to weld it back together. Very nice work I have to add. While he had it, he checked the difference in angle between the two knuckles using a digital angle finder. Would you believe .02 degrees! Not bad Ay? So, the next day I was looking up the torque settings for the steering knuckles (ball joints) in the FSM and came across something regarding caster that made me sick to my stomach. The angle on the knuckles is actually 1.5 degrees different. One is 6.5 degrees and the other is 8. Well, there wasn't much I could do at that point. I sure as hell wasn't going to do this again. Besides, there are a number of articles on the net from people that have done this and they set both knuckles the same. So, I got over it and put it all back together. I took it out for a test drive and it feels just fine.
So there you have it. Oh, here is a complete list of the stuff I did to it...
3 inch Teraflex springs that are really 4 inches.
Another ½ inch lift provided by shackles for a total of 4 ½ inches.
1 ½ inch tummy tuck using the Teraflex Belly up skid plate and the M.O.R.E 1 inch motor mount lift.
Spring perches on front and rear repositioned for the correct pinion angle.
Front steering knuckles rotated to correct the caster. (Necessary to compensate for moving the spring perches.)
Installed new rear upper and lower shock mounts using the M.O.R.E extended upper mounts.
Installed Flowkooler high flow water pump and 180 degree thermostat.
So, probably the biggest and hardest part of this project was rotating the steering knuckles. It took a whole weekend of grinding to bust them puppies loose. I initially rotated the first knuckle 5 degrees since that's what it seemed to need. The next day after I got the second knuckle done, I rotated it five degrees and then compared it to the other one. Whoa! there was something wrong here. They were not even close to the same. I was under the impression they were the same. Anyway, at that point I just blew it off. It was my understand that it was very important for both knuckles to be extremely close. So that's what I did. I set them both for 7 degrees using a straight edge, a tape measure and a little trig on the calculator to set the angle on the knuckles while the axle was mounted up. I figured out pretty quickly that my welding skills were not up to the task of welding the knuckles back on so I got in touch the UNSTUCK (Josh) at the Rad Jeeper and got him to weld it back together. Very nice work I have to add. While he had it, he checked the difference in angle between the two knuckles using a digital angle finder. Would you believe .02 degrees! Not bad Ay? So, the next day I was looking up the torque settings for the steering knuckles (ball joints) in the FSM and came across something regarding caster that made me sick to my stomach. The angle on the knuckles is actually 1.5 degrees different. One is 6.5 degrees and the other is 8. Well, there wasn't much I could do at that point. I sure as hell wasn't going to do this again. Besides, there are a number of articles on the net from people that have done this and they set both knuckles the same. So, I got over it and put it all back together. I took it out for a test drive and it feels just fine.
So there you have it. Oh, here is a complete list of the stuff I did to it...
3 inch Teraflex springs that are really 4 inches.
Another ½ inch lift provided by shackles for a total of 4 ½ inches.
1 ½ inch tummy tuck using the Teraflex Belly up skid plate and the M.O.R.E 1 inch motor mount lift.
Spring perches on front and rear repositioned for the correct pinion angle.
Front steering knuckles rotated to correct the caster. (Necessary to compensate for moving the spring perches.)
Installed new rear upper and lower shock mounts using the M.O.R.E extended upper mounts.
Installed Flowkooler high flow water pump and 180 degree thermostat.
UNSTUCK
But stuck more often.
I remember someone asking Kevin to post up the process of the caster adjustment. I don't have pictures of every step, as I recieved the axle half way through the project, but I'll share what I have and explain the process a bit.
Kevin did a good job of grinding down the welds (but maybe got a little crazy with the hammer) and placing the knuckles where he was happy with them, then tacked them in place.
After doing a little clean up, it was ready to weld.
For a little extra peace at night, I welded the inside of the axle tube and the inner C's.
The finished axles with new ball joints and pinion seal installed.
Kevin did a good job of grinding down the welds (but maybe got a little crazy with the hammer
) and placing the knuckles where he was happy with them, then tacked them in place.After doing a little clean up, it was ready to weld.
For a little extra peace at night, I welded the inside of the axle tube and the inner C's.
The finished axles with new ball joints and pinion seal installed.
