The front suspension was revised. That is the reason why zone does not recommend using the old-style control arms. Suspension droop is the biggest problem. Most people don’t take these trucks off-road getting a wheel or wheels off the ground putting the additional stress maxing out cv angle and ball joint angle.
I can’t remember where I read specifically about the UCA difference but this article explains our suspension very well.
Engineer Dan Edmunds takes a deep dive under the Ram 1500 to explain its trademark coil-spring rear suspension.
www.autoblog.com
I thought the BDS control arms were around $350. I was confusing that with the rough country upper arms.
Now here’s the funny thing... take a look at the upper control arms from BDS.
SUSPENSION SYSTEMS LEVELING KITS LIFT KITS 0 to 3.5" LIFT KITS 4 to 5.5" LIFT KITS 6 to 7.5" LIFT KITS 8 to 10" LIFT KITS SUSPENSION UPGRADES CONTROL ARMS 4-LINK ARMS RADIUS ARMS UPPER CONTROL ARMS SPRINGS ADD-A-LEAF BUSHING & HARDWARE COIL SPRING SPACERS COIL SPRINGS LEAF SPRINGS LEAF SPRING...
bds-suspension.com
They are listed as fitting a 2006 through 2020 ram 1500. BDS and zone are the same company. Now obviously these are two different products and the BDS Arms add 1.4° of positive caster. That will move the wheel forward and give more clearance for larger tires. It is not an OEM spec arm therefore I would have to assume logically that’s why it would fit 2006 through 2020 trucks.... interesting.