I just found your post. Here is my experience related to steering issues and tie rod replacement. I paid 500USD for replacement of all 4 - the parts are around 210USD (2 inner tie rods and 2 outer tie rods). I am very happy with my steering now - I understood tie rods are a wear item and normal to replace, especially if you drive 50k miles per year and more.My inner tie rods are showing some end play (very little). So I went looking for new ones. Ram is not offering them yet. I did find some on E-bay for this van a 2014 3500. They showed up and I can tell you if anyone has actually installed these TAKE THEM OFF! I sent them a return request stating they don't fit my application. They don't understand it as they claim they've sold a ton of them with no issues. Side by side comparison should be enough to make you stop and ship them back. They are very light duty, the ball and socket are 1/4" smaller in diameter. The shaft size is 3/32nds of an inch smaller in diameter (past the threaded area). Just FYI is all. If you purchase these for your promaster look them over really good. I suspect sooner or later one will brake and someone will be hurt or worse. These are made in Taiwan and sold by a couple of sources on E-bay. The rack on these are the same for diesel and gas models from my understanding. Inner tie rods (OEM) for the Ducato branded vans are available, so I may order them just for shits and giggles and see if they fit. Of course the dealer has no idea if they interchange. For 30 bucks vs 1,500 it's worth the gamble. The Taiwanese ones range from 200-300 for a pair. 512,000 miles still going strong.
I bought a few from this guy, worked very well so far..I bought several inner and outer tie rods on ebay, just search for Promaster tie rods in ebay, (I won't advertise here).
I always buy the cheapest BUT NEVER the ones from TAIWAN, always the ones shipped from US.
Mine worked super well - got mostly MOOG parts, sometimes another brands, cannot complain about quality at all!
The guy I'm buying sells inners and outers - you need to know how to replace them though or get a mechanic.