I'm buying parts from different sources. I purchase my "consumables" from Geno's and the local Cummins dealer. I've bought replacement parts from any number of places, Amazon, Silverline, Dodge dealer, TST, Borgeson, etc. Just depends on where I think I'm getting the best quality and value. I repair my truck for long term reliability so price might be a secondary consideration to quality and reputation.
Your symptoms sound very similar to what I dealt with on my truck, fluid and vacuum leaks. I'd definitely suggest you inspect your oil pressure sending unit and power steering high pressure hose between the pump and steering box. And, I'd recommend replacing these if your truck has 100k+ miles.
I had fluid leaks in both places. They were hard to detect because the drips on the garage floor were not directly under the left front. I had drips coming from the right front, bottom of the bell housing, oil pan and front seal area, etc.
The power steering leak was sneaky. I found that the power steering fluid was dripping out of the hose, down onto the top of the steering box, onto the left frame rail and the sway bar, then ran across the sway bar and dripped off the right side of the truck! I finally did see the leak when I had my wife spin the steering wheel lock to lock very quickly. Sure enough, I saw the drip come out of the hose right on top of the steering box. Changed the hose and no more leak.
I then changed the oil pressure sending unit because I started to notice my oil consumption going up and I still had drips on the garage floor. Once changed, the drips were gone and the left side of the engine was dry again. Of course I still have the drip from the crank case breather but I no longer have drips from the bell housing or front seal area. My garage floor drip pattern is now back to normal and my oil consumption is back to the quart every 4k.
I also pulled my vacuum pump thinking I had a fluid leak at the mating surface with the front cover or at the power steering pump. I didn't have a fluid leak but found two more problems. My vacuum pump drive gear was missing a tooth and the vacuum pump nipple was very loose. How in the heck the gear lost a tooth is anyone's guess. I didn't find any damage to the mating gear when I rotated the engine completely through. I bought a remanufactured pump from Pete Gould, loctited the vacuum nipple into the new pump, and put everything back together. No more vacuum leak and dodged a bullet with the missing tooth.
The vacuum pump tooth loss still has me scratching my head. I pulled the front cover several years ago to check the KDP (fully seated but I still installed the TST tab) and replace the front seal because I thought it was causing my leaks (it wasn't, still had leaks after the new seal). I suppose I could have left something in the front cover but you'd think it would have caused damage on the mating gear or others as well. Anyhow, make sure you inspect your gear very carefully if you decide to pull your vacuum pump.
Good luck on your repairs.
Dave
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