We might need an attorney to define contract language. But as an Insurance broker. I can take a pretty good stab at answering this.
Dodge (or whomever purchases the viper brand) has a duty and responsibility to fix,repair,replace,etc any "covered" items that fail under the warranty "term", as defined by your in-service date and mileage. This responsibility does not end or change IN ANY, WAY, SHAPE OR FORM if the company is sold.. Who ever purchases Viper, would have to factor this (tail/spin-off) liability, into their offer. And most likely work a deal with Dodge to continue honoring warranty claims, at Dodge Dealers (on a sub. basis). Same thing goes if the Viper is discontinued. The "write-off" amount of that company. Would have to include future warranty exposure/liability.
If Viper is sold, a number of things could happen. And I would have to read my whole warranty contract to answer this. The question is, "can they change service providers or use a third party" and change your contract mid-term? They probably CAN.... Simply because if Dodge (or any company for that matter) went out of business. They would obviously have to push servicing the remaining balance of warranty cars, off to another brand/repair shop. So, Im sure there is language which states this, in any warranty contract. The question is, does Dodge have to go out of business for this to take place? Or would this apply if Dodge just sold the brand name?
It really doesnt matter though. Unless Dodge/Cerberus (and all of its companies) were going out of business. It simply would not make business sense to have these cars warrantied elsewere. Allowing "Brand-X" to start doing warranty repairs just because they now own the company makes ZERO sense.. Could you imagine the logistical nightmare of training techs,stocking parts,ordering parts through Dodge,etc.. No Matter what happens, they will find a way for us to continue to use Dodge dealers for service. It makes sense for them, plain and simple.
As for "service contracts" and cars that have expired "factory" warranty... Nothing at all will (or could) change. Service Contracts in an Insurance Company, and seperate from Dodge,Chrysler,Jeep. They will provide coverage no matter where you go for service. As long as time/parts cost are in check.