In my research for long travel design, I have come across kore high angle inner cvs that increase operating angles from 19 degrees to 30 degrees, supposedly matching that of the outboard cvs. This alone could potentially yield significant gains in flex/wheel travel (2-1/2") and coupled with 3" longer CAs the difference would be dramatic; 14+ inches of wheel travel could be possible with other modifications. These are marketed for ram 1500s, but should fit considering the cv axel assemblies are identical except for the length, from what I can tell. Unfortunately, they are 800$ a set. Also, there are many other inherent limitations on this trucks suspension/wheel travel which must be overcome in order to benefit from these. This is based on a tape measure, my truck, and autocad; it is not scripture.

My truck is leveled and when I am at full droop (front wheel off the ground) while driving, I experience a violent shudder in the drivetrain (the shift **** jerks out of my hand). I don't know, but I suppose the cv could be binding and backlashing against the diff which is attached to the motor and trans and causing this. The point is, that at full droop on a leveled truck you could be and probably are exceeding the safe operating angle of the cvs.

 

wow the ram 1500 cv axles are literally the same as the dakota ones just a longer axle shaft. 66mm (2.6") exactly. If you ran a diff drop and ram 1500 cv axles you might could get away with 3" longer CAs and tie rods if they are put down at an angle by something like a strut spacer... not quite long enough but they would be articulating on on a similar circle to lca but at a lower angle so they wouldn't need to be lengthened as much as the lca. Most people don't like the idea of their diff being lowered and exposed but personally i dont thing 2" is going to make a difference just get a strong cover i think jmr or somebody sells them

 

I plan to use fabbed CAs and tie rods that are longer with the ram cvs. I will not be dropping the diff. I will adjust the ride height up a little bit with the preload on a set of 10 or 12" coilovers. I will make as much room as I can for 34 or 35 " tires by removing body work and/or fiberglass fenders. Eventually, I will alter the ram axels with the core cvs to get max wheel travel.

 

I don't think it's a good idea to drop the diff and not the CAs. AFAIK, the axels, CAs, and tie rods should be somewhat parallel. 2" May not mess with things too much.

 

I see that a lot but no one has been able to explain why. I thought that the axle shaft moved back and forth a little bit anyways since the camber changes on up/down travel so it won't hurt it in that way if the diff is dropped. Maybe has to do with the angle of the axles when torque is applied to the hub compared to the angles of the cas and tres. Any idea? I feel like someone here knows but just isn't chiming in.

 

Hard to explain w/o pictures. In theory, if the CV pivots and CA pivots are all in the same plane and the arms and shafts are all parallel and the same length, they will move exactly the same and the CV would not need to plunge at all.

The UCA is shorter in reality and angled to create desirable characteristics in suspension/steering dynamics. (for example, the outside wheel in a turn increases its camber as it compresses the suspension effectively making the wheel lean into the turn like a motorcycle). The steering of the knuckle also moves the CV axel, requiring it to change length. That stuff can be complicated and counter-intuitive. For basic understanding we should imagine the ifs as above, with everything the same length and parallel and having pivot points in the same plane relative to each other. Look at the IFS from the front and imagine one half of it as a rectangle: the CAs being the upper and lower horizontal sides, and the knuckle and frame rail being the vertical sides. Remember, a rectangle's opposite sides are parallel, and equal in length, and all four angle are 90 degrees. Now imagine the frame side in a fixed location and the knuckle side moving up and down in an arc (like it does in real life). If you imagine the CV axel as a third horizontal line attached to the mid point of both ends, it would move exactly the same way as the two CAs and would not need to get longer or shorter.

If the CAs are angled down and the CVs are horizontal (if I understand you correctly), the CAs will effectively get longer (toward the outside of the vehicle) as they cycle up during suspension compression and get closer to horizontal. The CVs will effectively get shorter (move inboard) as they move upward and depart from being horizontal. The outboard ends of the CAs and CVs would be moving in opposite directions as the suspension cycled up.

In the same situation, if the suspension drooped, the outboard ends of the CAs and CVs would both move in the same direction (inboard), but at different rates.

To answer your question; I think the CVs would have to plunge/extend too much if they are not parallel with the CAs.

 

That was actually a perfect explanation. I could have know nothing about IFS and understood that. So if the issue is only the amount of plunging then there should be a problem. I know smitty28 is running the JMR 2" diff drop with a 2.5" leveling kit and EVguy is running a 3" drop with a 3" leveling kit and as far as I know they haven't had problems yet. What I said about the CV axle shaft not having to be lengthened as much as the CAs was wrong though since the CV axles would reach horizontal and start moving inward while the CAs would still be angled down and moving outward during compression.

 

that combination would work. but to do it right i would get kore cvs and have kartek cut some 300m axles at exactly 3" longer with the same spline counts. your going to get plunge no matter what you do. its not AS critical to have the cvs on the same plane as the lower arms because theres really no ill effect. but it is super important to keep the tie rods on the same plane for safety reason and bump steer during cycle. the last thing you want to do is hit a dip in the road and the truck darts off in another direction.

the perfect combo for you 4x guys would be the kore ram cvs, extended axles, upper and lower CAs, extended tie rods, and brake lines....thats probably all you would need....

unlucky for you guys is that you cant run lift spindles on 4x4 because the lower uniball becomes centered on the hub with lift spindles...lucky for us 2x guys is we get an extra 3" of lift out of spindles without dipping into our travel

 

Yeah I hate you guys with 2x. My lift will all come from tire, shooting for 35s, 34s for now. I might drop the diff someday. I m going to try the ram axels as is. With 20 degrees of flex and longer arms we could see 12" wheel travel. With the kore inners we could go to 15" if you start cuttin up the truck. The stock ram cvs are .4" short, but I think they will work. If they don't I will lengthen mine. The kore inners will fit either.

 

I'm not going for LT so I'm just going to go with a drop when I can afford new arms. Not even converting to coil overs.

TBH I kind of want a 4x2 for my next 1/2 ton. Most 4x4 are just open diffs with a locking t-case so a 4x2 with a locking rear wouldn't be a huge loss.