I am looking at 2 different 1999 3500 Dually's 4x4 Crew Cabs, one has the 454, the other has 6.5 diesel, let me hear the differences, who likes what better?

Fuel Mileage is NOT an issue.

The truck will be mostly empty, except for 2 weekends a month during the spring-fall, one weekend boat to the lake, and the other is a K5 on a trailer to the Con.

What will be the trucks primary use? The 454 will pull better, but get lousy gas mileage. The 6.5L diesel will get good mileage (about double the MPG of the 454), but won't pull as well (nor will it perform on the street as well either). Also, the 6.5l's reputation for longevity/reliability is questionable.

If it were me, I'd get the 454 if mileage isn't a big concern. If mileage is a big concern, I'd look for a different truck.

Ditto. The 6.5 is rather anemic. I had a 97 with the V454 and 4.10's and it towed extremely well. I averaged about 10-12mpg but I had issues with the skinny pedal.

I'd definately go for the 454 if everything between the 2 trucks are equal. The 6.5's don't make alot of torque and are not a reliable Diesel, probably why GM didn't keep it any longer than it had to.

sounds like you have some sort of answer, you hade it right about he fuel mileage verses the monthly payment.

454;)
just recently i had a friend with the 6.5 try to pull his rover in a enclosed trailer on the freeway...he was going lik 40mph going up hills on the freeway

Go with the diesel. Better milage and it will last longer. The 97 and newer have a good rep and not many problems. I have a 98 and with the 4.10 gears it will tow anything a 454 will tow. I have hauled plenty of trucks with it that weigh more than a K5
The 6.5 is rated for 195hp and 430tq. I think the 454 is rated for 290hp and 410tq of the 99 model year

Originally posted by Joey D
Go with the diesel. Better milage and it will last longer. The 97 and newer have a good rep and not many problems. I have a 98 and with the 4.10 gears it will tow anything a 454 will tow. I have hauled plenty of trucks with it that weigh more than a K5
The 6.5 is rated for 195hp and 430tq. I think the 454 is rated for 290hp and 410tq of the 99 model year I hope you don't take this the wrong way but if your 6.5 actually pulls well and doesn't suffer from various component failure yours is an exception to the rule. I've had personal experience with several 6.5's and all suffered expensive failures, usually the pump or the fuel driver. None of the 6.5's pulled well for a turbo Diesel either in my opinion.

The 94-98 have a 11 year 120k warranty on the pump, which covers the FSD as well. Most of the pump problems have been addressed with updated pumps. I have had zero trouble with my 6.5. I can't be the only one. This has been my 1st diesel bought new in 98 and to date no trouble. I can be hard on it, sled pulls and such as well as plowing snow.

I would go with the 454, mainly because I rarely hear anything good about the 6.5's with the exception to Joey D and a few others over the years. I pull with a 97 4x4 454 dually and it serves me well, just not the fastest rig going up grades with a load behind it. But as a daily driver its a great rig, and has the power to keep me happy!

Originally posted by Joey D
The 94-98 have a 11 year 120k warranty on the pump, which covers the FSD as well. Most of the pump problems have been addressed with updated pumps.


while they did honor the extended pump warrenty for me when i had mine....the thing was still a POS. my 96 got a new pump in 98 and then a new everything-else in 99. the pump started fawking up just about a 7 months later. i had more problems with that truck than i could shake a stick at. get the big block.

Go with the 454 or get a cummins