WILDHOBO
Well-Known Member
My lowers are very close to that. Just over 24.5. Couldn’t get an upper measurement, but I adjusted them recently and kept the number. I just need to find it.Rough numbers:
UCA = 20.5
LCA = 24.75
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My lowers are very close to that. Just over 24.5. Couldn’t get an upper measurement, but I adjusted them recently and kept the number. I just need to find it.Rough numbers:
UCA = 20.5
LCA = 24.75
Yes, you are making my point that touching the steering box adjustment is taboo, as sometimes it’s the root cause of a problem. Unfortunately, that’s not generally discussed on steering box threads, which is why I posted my experience. Folks have to decide for themselves if it’s worth the risk messing with the gear box.Your steering gear has an absolute problem if you had to go a full turn. It may work, but it's a problematic gear.
The thing is - it may not "ruin" it in the sort term, but it definitely won't last like it should, and isn't right if you simply turned it to take slop out.
The fact there was actually play says - that box was poorly set up, or has another issue inside.
It's not just me saying this - it's the tech manuals, the factory rebuild documents and more. I went through these things in college, and later - properly building and setting them up.
You got damned lucky - having to keep adjusting it just confirms there's a real problem with it inside.
A good one doesn't require any adjustment for at least 100,000 miles or more. Usually the car is toast first.
What you are measuring there is a fixed measurement. The axle and the c's have 6 degrees of separation. When talking about pinion angle, it's the angle between the pinion (input of the diff) and the drive shaft. As you lift a vehicle the angle of the drive shaft to the pinion increases. As you adjust your control arms to get your caster set you will be increasing the pinion angle. It's always a game of give and take. Once you get to lifts of 3.5" or more, you should be considering double cardan drive shafts that can operate at steeper angles.About to check my lengths.
Here are my current angles. Floor is almost 0, but the comparison should be more important I think.
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We also talk about pinion angle for other reasons - such as setting it to figure caster.What you are measuring there is a fixed measurement. The axle and the c's have 6 degrees of separation. When talking about pinion angle, it's the angle between the pinion (input of the diff) and the drive shaft. As you lift a vehicle the angle of the drive shaft to the pinion increases.
Assuming a 6 degree difference in the pinion vs. the "C"s welded to the axle tubes, if the pinion is at 0 degrees, or perfectly level, or, if you measure from the machines face of the differential and it's 90 degrees (perfect right angle to the ground) then you have 6 degrees caster. Assuming your tubes are welded properly and the tubes haven't twisted at all.My lowers are very close to that. Just over 24.5. Couldn’t get an upper measurement, but I adjusted them recently and kept the number. I just need to find it.
I actually do get all that. My issue is that I have the 4hi auto transfer case. I have a brand new double cardan 1350 shaft on the garage floor, but I’ve resisted installing it. I’ll almost certainly have terrible vibrations with it. So I’ll need to improve my pinion angle, which is currently around 18 degrees (horrific), without destroying my caster, which is near impossible unless I’m fine with terrible spring bow.What you are measuring there is a fixed measurement. The axle and the c's have 6 degrees of separation. When talking about pinion angle, it's the angle between the pinion (input of the diff) and the drive shaft. As you lift a vehicle the angle of the drive shaft to the pinion increases. As you adjust your control arms to get your caster set you will be increasing the pinion angle. It's always a game of give and take. Once you get to lifts of 3.5" or more, you should be considering double cardan drive shafts that can operate at steeper angles.
I’m going to try decreasing my caster to around 5 degrees to see how much better the drive shaft angle is. My concern is mostly how close the shaft is to the exhaust crossover.We also talk about pinion angle for other reasons - such as setting it to figure caster.
Since there are 6 degrees difference, you can measure the angle of the pinion compared to 0 and know your caster.
If the pinion sits at 0 degrees, you have 6 degrees caster.
Tip the pinion up and you lose caster, tip it down, you gain caster. So yes, you can measure the pinion to gauge caster.
I'm sure he knows about joint angles - he's been down this path many times over the years.
You measure the pinion angle and the driveshaft angle to get the joint angle.
I've got a tool that dates back a few decades that does all of that work for you, as well as magnetic angle indicators, and have an app on my phone.
I had to adjust the pinion angle on my SX4 because the crappy cheap rear springs I got were arched wrong and set the differential angle wrong, giving me too much joint angle (really short driveshaft so it mattered a lot).
Assuming a 6 degree difference in the pinion vs. the "C"s welded to the axle tubes, if the pinion is at 0 degrees, or perfectly level, or, if you measure from the machines face of the differential and it's 90 degrees (perfect right angle to the ground) then you have 6 degrees caster. Assuming your tubes are welded properly and the tubes haven't twisted at all.
Can you snap a pic of your front diff/driveshaft from the drivers side wheel? Behind the wheel is fine. Using your angles in the pics, you either have 5.5* or 6.5* of caster. I couldn't tell if that 89.5 from the front casting was a half degree rolled forward or a half rolled down.I’m going to try decreasing my caster to around 5 degrees to see how much better the drive shaft angle is. My concern is mostly how close the shaft is to the exhaust crossover.
Smart - did the research before just tossing a wrench on it like the blind leading the blind do on the YouTube videos.Last time I went to the alignment shop, had em set mine to 5.5 caster and as best I can recollect, .04 Deg on toe in. Had to go a bit less than the stock parameter because of tire size (42). I manned up and took some of the backlash out of the steering box cuz it had a Shit-ton of excessive backlash. You can find plenty of info on how the gear sector works and what the adjustment does. once that is understood, super easy to adjust as required to get the slop out without destroying the box. I did mine at 32K on the odometer and just passed 111000. No issue. It had somewhere near .100" on a dial of slop. Took it down to somewhere near .030" which was just before I could feel it getting tight at lock to lock. Huge difference. I run my 42's on the reg at 85-90 on the highway with zero problems whatsoever. My truck is still a one finger on the wheel rig. Which still surprises me since I have spacers behind my Methods to get em to clear, so my scrub is not good. It wanders with the ruts a bit, as would anything with 42's, but I really can't complain about how my truck drives.
Oh yeah, forgot:
2.5 Ton steering from Fuzion
Sector brace
Falcon stabilizer
Rebuilding the axle side track bar hole as it got wallered' out.
I replaced pretty much everything![]()
I also have the auto awd transfer case, but I never use it. I only ever use 2wd or 4lo. I'm only on a clayton 2.5" lift, so the stock shaft is holding up fine.I actually do get all that. My issue is that I have the 4hi auto transfer case. I have a brand new double cardan 1350 shaft on the garage floor, but I’ve resisted installing it. I’ll almost certainly have terrible vibrations with it. So I’ll need to improve my pinion angle, which is currently around 18 degrees (horrific), without destroying my caster, which is near impossible unless I’m fine with terrible spring bow.
The problem with those after-market shafts with a single cardan joint at one end and the double at the other is - great, one end can work at a large angle, but the other can't because there's nothing to cancel out the shaft's speed changes from that single joint.I actually do get all that. My issue is that I have the 4hi auto transfer case. I have a brand new double cardan 1350 shaft on the garage floor, but I’ve resisted installing it. I’ll almost certainly have terrible vibrations with it. So I’ll need to improve my pinion angle, which is currently around 18 degrees (horrific), without destroying my caster, which is near impossible unless I’m fine with terrible spring bow.
Sure. I’m pretty sure 6.5. I threw the angle finder on the driveshaft as well. It was less than I thought, but still pretty bad.Can you snap a pic of your front diff/driveshaft from the drivers side wheel? Behind the wheel is fine. Using your angles in the pics, you either have 5.5* or 6.5* of caster. I couldn't tell if that 89.5 from the front casting was a half degree rolled forward or a half rolled down.
Agreed. I just hate to toss all this investment in these housings. Shafts, ball joints, knuckles, skids, steering, etc. is a ton of cash.I also have the auto awd transfer case, but I never use it. I only ever use 2wd or 4lo. I'm only on a clayton 2.5" lift, so the stock shaft is holding up fine.
You could always go to an aftermarket axle that has 10 degrees of separation. An expensive solution though.
Not saying it's needed, but inner Cs can be turned. A good shop can cut the C loose and reset it at a different angle relative to the pinion.Agreed. I just hate to toss all this investment in these housings. Shafts, ball joints, knuckles, skids, steering, etc. is a ton of cash.