What is a "workhorse p30" ?

darin338 wrote:
Purchasing a 2000 Newmar Dutch Star. Owner says it has a GMC 7.4 which I believe is a 454?

However, the carfax states it is a "workhorse" p30, which I always thought the workhorse was Chevy 8.1, not GMC 454?

Also, I've searched and searched and searched and have yet to find another 2000 Dutch Star with a 7.4 GMC in it. They either all have the V-10 or are diesel.

The 8.1 (just a little more stroke than the 7.4 for the most part) were in later P30 chassis (a generic term and actually refers to a P32 in Motorhomes) that was bought from Chevy GMC in 1999. Most are found on the later Workhorse W chassis, however. At any rate, you're very close to a transition year for those engines. The 7.4 is yes, 454 cu in., but not called that with the use of the metric system to describe the later non-carb fuel injected engines.