There are several aftermarket exhaust brake options for your (I am assuming) older 7.3l diesel such as Banks, BD, Pacbrake, and D-Celerator. I haven't ever heard anything bad about any of them but since they are all aftermarket you will have to learn the particulars about each of them as they all differ a little bit. Expect to pay around $1500+ for everything before install with Banks being likely the most expensive (of course). Some people even electronically control the heat riser valve and transmission torque converter and use that as a less expensive "sort of" exhaust brake. I think BD calls it a BrakeLoc. Expect to pay $400-500 before install. I would suggest going to a good Superduty truck website forums like ford-trucks.com or powerstroke.org in order to get more info.
A lot of the 7.3l owners will upgrade their brakes and find that a exhaust brake is less necessary unless you are pulling more than the truck is rated for. Unfortunately with your 7.3l F350 you will find you will run out of payload long before you get to the GCVWR of the truck. Slotted cryo'd rotors and high performance pads help quite a bit and are cheaper tun a exhaust brake if you stay within your ratings.
I would rather mod the brakes than add on to the engine something it was not built for.
2016 F350 6.7L LB CC Reese 28K 2014 Chaparral Lite 266sab
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