I see that you are in Oceanside. Is your dealer Johnson, Quinn, Hawthorne or other? It's been a while since I've lived/done work in SoCal and I know that there have been some changes and acquisitions since I left there over 20 years ago. That being said, Quinn was my dealer back in those days and they set the bar pretty high back then. Even still, there were some instances when I had to "call them on their sh!t", and when I did, they responded and made things right.
Certainly you should go higher up the chain to discuss your issues. You might be surprised at what may come of this before you just write them off as not giving a poop. I have also seen the personnel, and corporate issues that are being mentioned here. That being said I still believe that if you go up the chain high enough you will get some assistance.
Furthermore, we all ultimately have to take responsibility for our own situation/s. Per what he is saying the OP has likely bit off more than he can chew (as it relates to the machine, and his workload) and this is something that many of us (especially those of us who own our own businesses) have to learn about....Sometimes the hard way. Many of us have done so and, thankfully, many of us have learned immensely from this. That being said I feel that both parties (the OP and the dealership) have some responsibility here if the scenario is being told accurately. As you are now attending the school of hard knocks, you have seen the value of good support. If you can't find the support you need from CAT (which in my experience with more than one dealer, in more than one state, and also experiencing a decline as has been mentioned here, still feel they are top of the class) then maybe unloading this particular D8, and switching brands might be the way to go.
As it relates to spending the money on this machine, I think that there is wisdom in seeing this one through the repair (as John C, and the OP have eluded to). At least it will then be a mostly known commodity.
To the OP: I feel you and all your struggles. I am routing for you. I hope that the engine does not become another trouble spot for you and that you can get the fuel leakage issue taken care of, inexpensively and with out finding any further damage.
As it relates to the original query this thread has gone a little bit off the rails (pun intended
). Is there anything else the OP needs to know about which way to go with regard to purchasing aftermarket or OEM?
I think it was Nick that suggested that CAT U/C was the highest cost per hour. Is this true? If so, which is the least cost per hour?
In my experience I have found that the CAT parts usually cost more but work out to be a lesser cost per hour due to the extended life span. I don't have any dozer U/C replacement experience so I would love to see where a discussion about this would go.