2nd Gen Non-Engine/Transmission Double CV on Front Driveshaft

[Ereynolds72]

After installing 2. 5" lift coil springs, I developed a vibration and a very mild case of death wobble. After doing a bunch of reading here on the site, and after wasting $90 at an alignment shop, I adjusted caster positive. That eliminated what death wobble completely. It actually felt better than it ever had once doing this adjustment. Doing this though, I had but obviously lowered the pinion angle and the vibration actually became worse. I don't want to sacrifice ride quality and driveability by adjusting the caster less positive so now I'm driving without the front driveshaft.



To address the vibration issue, I was thinking about having a 2nd CV joint put on the front shaft. Has anyone seen this done before? Would there be weight issues on the pinion bearings. Mine is an '02 so the entire assembly turns all the time.



I also like the new flange connection on the 3rd gen. trucks better than using straps on the u-joints at the front pinion (and rear for that matter). Is there a conversion available to replace the strap style yoke with a flange?

 

[Ereynolds72]

Bump... .



Still trying to resolve this. I was looking at the adjustable ball joints from Ingalls Engineering. Part #61000 or #61500 is supposed to allow 2. 5* caster adjustment in addition to allowing camber to be adjusted. I've seen that a few guys have installed these when replacing their ball joints and was just curious as to how it all worked out for them. In my case, I need a little caster adjustment independent of the pinion angle to maintain the ride and driveability yet eliminate the pinion vibration I'm experiencing. Any thoughts on this would be appreciated.



Erik

 

[Ereynolds72]

How 'Bout this idea??

Okay... here's another solution I've been contemplating. If I increase caster (or leave it where it is in my case), it lowers the pinion creating a scenario illustrated by the 2 joint illustration. If I decrease caster, it raises the pinion and creates a scenario illustrated by the CV drawing but I'll lose my driveability.



I am wanting to try a regular 2-joint driveshaft for my front driveshaft but am leery about spending 2-3 hundred bucks without some other feedback.

Thanks for the help,

Erik

 

[Joe Mc]

How many miles on the suspension components before you raised/leveled things out? You may have brought to life something that was inevitably going to happen when you raised/slightly changed geometry. I'd try to KISS it - check the simple stuff first: how's the track bar? It's angle has increased which puts more stress on the joint. Are the drag link joint and others good = similar play. Pitman arm tight? Knuckle joints tight? The other possibility if you raised it enough it could (probably did) have moved the diff to the left (I think) because the track bar didn't get longer. You can check this by placing a straight edge along the wheel that will extend above the wheel house molding and measure distance between it and the straight edge. Then compare one side to the other. You may be out of kilter side to side Vs pinion angle??? Another way to check this would be drop a plum bob from similar points on the frame to the diff housing and see if they hit the same spot on each side - don't know about this last idea just seems to me it might work? The things you are looking at doing with adding the CV sound like $$$ that could be better spent on some other HP mods - assuming it can be figured out without having to throw $$$ at it. Let us know what does it for you.

 

[Joe Mc]

I forgot about the other question re: straps that hold the "U" joints in @ the diffs. I've drilled out the bolt threads and replaced with small "U" bolts specifically for "U" joints like on a (Furd) 9". I've always hated those wimpy straps - droped more driveshafts banging second with my Duster than I like to remember before I drilled and took straps off my Mustang to solve the problem.

 

[Ereynolds72]

I had about 65k miles on it when I installed the suspension system. I had the front DS completely rebuilt and balanced. That didn't help. The axle is pulled to one side a little. I'm aware this is a function of the track bar not being lengthened. All the other steering components are still tight.



If I adjust camber back toward the negative (i. e. moving the lower ball joints rearward thus rotating the axle and pinion upward toward the transfer case) I can install the driveshaft with no vibration whatsoever. However, with the caster now adjusted with less than optimum caster setting, the steering feels sloppy and it doesn't track as well. I want to put a new adjustable track bar on and convert to the HD T type steering system but really, everything is still tight. To me, it's the simple fact that caster is not independantly adjustable of the pinion angle. I've tried incrementally adjusting the caster/pinion angle to where the driveshaft doesn't vibrate yet maintain decent drivability but I still don't feel it's enough caster.



I'm not sold on having two CV joints but converting to two single joints with a slip shaft/yoke similar to the rear driveshaft. I may try that. I had one guy give me a price, then I was relocated with work. I can't find a DS shop now that will make one. They all say it will vibrate worse. I trust their judgement... and I appreciate they don't want to see me wast money but I'm just trying to think outside the box.

 

[BigEasy]

You can't use 2 CV's on one shaft... it will allow the shaft to flop all over. A simple solution to your problem would be to lower the transfer case, or as I have seen done on custom setups, cut the knuckles off the ends of the axle tubes, then reorienting them and welding them back onto the tubes... you can set your pinion angle anywhere you would like. As you can imagine, This is a complex precision job.