I am working on purchasing a 2012 550 rescue body truck for a local fire department and need some well informed input. I have been reading and I am concerned about cab and chasis trucks dropping exhaust valves, obviously a rescue body truck will start out as a cab and chasis and I don't want this rig to fail while trying to respond to a call, both causing me issues and leaving those we serve without assistance. Are the newer production trucks having more success or is this an across the board issue? Our current truck is a 7.3 powered 550 and has had a flawless service life and I know it will be hard to compare to old faithful but we count on the reliability of the truck. And there are several who want to go down the path of a d-max powered truck (don't crucify me, I love my ford!) but to stay with a light rescue body gmc only offers a 3500 series, and we are like every department around the country and we overload everything so a 550 would be better but I need to know what to look for when looking at a 6.7 truck and knowing which production numbered/ pcm flashed trucks I need to look for. Think of it this way, if you needed help, which rig would you put your faith in to bring you assistance? thanks for any and all input.

 

I can't add much to your question because I don't have direct experience but if you do decide to go with a new truck (any new brand diesel truck), you may want to consider this device below.

Paul was an engineer during the 6.7L build project and he made a post about OCR awhile back.
Unsure if this is for a 2012 though so consider that.

Most rescue trucks idle a lot (they do here) and run hard when they need to respond and that type of driving hasn't been friendly towards DPF's.
This device is supposed to allow you to run a manual active regeneration and the 2012 cab and chassis models do have a screen that reports DPF plugging based (I think) on percentage to the operator.
This would seems it would at least help prevent DPF related failures by keeping it clean.

https://www.ford-trucks.com/forums/1...ions-info.html

Maybe Cheezit and Vloney will add their experience here.

 

I have a 2012 6.7 F450 just purchased, but I also have a 2011 F350 and have been browsing this forum, and the heavy duty for years (had a 2006 6.0 F450) I have not heard of any valve issues, or any other issues for that matter. I know the cab and chassis are tuned different than the pickups. They have like 300/600 instead of 400/800, but they are designed to pull the weight. So far, I have only had about 4,500#'s out of a capacity of 6,500#, but, absolutely no issues driving around with 70% loaded. Hardly feel it in acceleration.

 

well i can let you know ive got one of the first cab and chassis f350 build only had water pump replace and rear seal in rear end replace ive got 38,000 miles on it