Best cat engine to purchase in used semi?

I have heard from more than a few owners that parts and pieces are getting very hard to come by, especially if in need of an in frame. Heads seem to be the big issue, the remans are crap due to the fact they have been through the mill one to many times and the Chinese ones aren't that good either... I would really do some research before purchasing anything made by Cat if you plan on keeping long term. I would call some of the Cat dealers and really dig into parts availability.

 

From about '76 on Caterpillar were Paccars preferred engine supplier. Unless you ordered something different, your KW or Pete came with a Cat

 

3406B, 5EK, 6NZ, 1LW, 2WS, 7CZ. Any of these motors will do a good job. Try to avoid the MBN, MXS, BXS unless the others aren't available.

 

Personally I'd look for a 3406 B or a 6NZ or anything pre 2003 because of emissions controls and computer issues.

 

Don't buy a C15 acert. No fuel economy, and very expensive to repair. Earlier cat engines are fine if you like paying extra for the name.

 

Cat c13 KCB 500hp.1291000 miles and not rebuild.have repair bills
from the last 8 years.Biggest repair was Turbo.Headgaskett.Camshaftroller and Cylinderpack .mpg ~6.8 with 68 miles/hrs

 

3406b or 6nz

 

Look I'm 3406B all the way through and through. I feel that throwing this motor out there is bad advice. The only reason I say bad advice is they are strictly 100% mechanical. Other than a few simple gauges or the timing indicator group that 99% of CAT dealers don't have any more there are no diagnostic aids. You have go by sound and feel. Yes to me they are very simple, to the guy who has only seen a few and a computer is his go to tool? They are a hand made grand father clock. Let the average late model mechanic around it and you will dump thousands and fix nothing. Let the wrong parts be used out of a salvage yard and you got a mess that can cost big. They weren't all the same. Just cause a piece will bolt up don't mean it will work. Now if the OP has a little experience or knows a good B model man without a foot in the hell yes it will do him a good job. Other wise a night mare looking for a pillow to happen