Carli's leveling full progressive rear leaf springs are a fantastic way to improve ride, control and handling on your Ford Super Duty truck. Designed to match a level height front, these leaf packs are offered in a few different configurations to ensure your capacity needs are met. All options massively increase wheel travel and articulation to over 12" so if you spend any time off road, it's a welcome improvement. These are also a critical part of softening the rear ride on your truck compared to the harsh, factory leaf packs- even on pavement. Carli leaf packs also mount directly to the axle, meaning you can eliminate the stock block and the axle wrap associated with them.
WHICH LEAF PACK IS RIGHT FOR YOU:
Carli offers these leaf packs in several spring rate variations depending on how you use your truck. The standard soft ride leaf packs are designed for trucks that spend any amount of time empty, and then have variable loads placed in or on them like trailers and gear in the bed. Since these are softer than stock, we pair them with these Full Travel Airbags to maintain towing capacity and variable bed load capacity. That allows you to have your cake and eat it too with soft daily ride and full ability to haul.
Carli also offers three levels of HD leaf packs. These are intended ONLY for trucks with full time in bed load like tool storage systems, in bed campers, service bodies, or welding beds. They are offered in the HD variant for about 500-1,000lbs of constant load, XHD variant for about 2,000 pounds of constant load, and XXHD variant for about 3,500 pounds of constant load. These can also be paired with Full Travel airbags for towing on top of the listed static loads, like pulling a trailer behind your truck with an in bed camper. We don't recommend these if your truck spends time empty, as you'll sit rear high and won't have the proper ride. These HD shocks also come with specific valving profiles of Carli Pintop shocks, so make sure to choose accordingly. We don't recommend using the HD leaf packs with any Carli 2.0 diameter shocks if it can be avoided.
UPGRADE OPTIONS:
This leaf pack can be optioned with shackles and pinion shims. We highly recommend adding Carli shackles as they improve ride and articulation compared to the factory shackles, which limit what's possible with the Carli leaf packs.
The Pinion shims are not mandatory, but can help reduce driveline vibration if present. This has been a noted problem on rare F-250 trucks, but it's not common.
NOTE: These leaf packs DO NOT work with stock shocks from any trim package. Sadly factory shocks are too short, and the valving is significantly off from from what is required with these leaf packs.
INCLUDES
-Pair of rear Carli Progressive Leaf Packs
-U Bolts
-Rear Bump Stop Drops
Customer Reviews
After weeks (okay, months) of obsessive research, forum lurking, YouTube deep dives, and pretending I understood suspension geometry, I finally pulled the trigger on the Carli Backcountry suspension and rear progressive leaf springs for my 2021 F250.
Let me just say: I knew what I was buying… but I still wasn’t emotionally prepared.
Install day felt like a mix between Christmas morning and a mild engineering exam. Once everything was on, I took it for a drive and immediately questioned every life decision that led me to driving stock suspension before this. Apparently, I had been willingly bouncing around like a shopping cart with a bad wheel.
Now? Smooth. Controlled. Confident. My truck glides over bumps like they’re just suggestions. Potholes? Never heard of them. Speed bumps? More like “speed recommendations.”
I also feel 37% cooler driving it now (scientifically verified). The truck looks better, rides better, and somehow has developed a personality. I swear it judges other trucks at stoplights.
The progressive leaf springs deserve their own award. Towing feels solid, unloaded ride is comfortable, and for the first time I’m not bracing for impact every time I see uneven pavement.
Would I recommend it? 100%.
Was it worth the research rabbit hole? Also yes.
Do I now look for excuses to go drive? Absolutely.
Only downside: now all my friends want rides and my wallet is afraid of what I’ll “upgrade” next.
Just installed the progressive rear springs don’t have many miles on them yet. Ride is definitely better but get the opinion shame mine had a vibration and had to take it back apart to install the shims.
I worked with Oscar on the build for my 2024 F250. Oscar was great, very knowledgeable, and was great at communicating with me throughout the process. My truck was in and out the same day, which is awesome considering it was a full Carli build. I have had numerous trucks built at different shops, including Kern County and Ventura County, and I HIGHLY recommend CJC offroad. I also love that they do the first responder discounts. I will definitely make the drive for any future work with CJC. 10/10
This was one of several mods installed on my F350 primarily to improve handling with the addition of a full-time slide in camper. Glad I went with the XXHD springs. Camper and equipment weigh in at about 2700 lbs and the XXHD springs are designed to work with a constant 3500 lb load. I don't think the XHD springs would have been enough spring for my liking. The ride with the XXHD springs and camper is smooth. Pintop Level Height system was also added to the front along with Carli Radius Arms, upper and lower steering stabilizers, the torsion sway bar mod, and 37 inch 13.50 Wildpeak tires mounted on Foundation wheels. These are all quality modifications/parts. Very satisfied with the results. I have about 3000 highway miles on this suspension/tire combination. The ride is smooth and comfortable. No side-to-side rocking when maneuvering which was a problem with the stock suspension. Feels like the camper/load isn't even there. With the stock suspension and camper, headlight aiming was a problem. These mods also restored a proper truck stance and the headlights are aimed properly. The truck feels good. I have not got off-road with this yet but I fully expect a satisfying experience there as well. Had CJC do the install and was very satisfied with their customer service and quality.
Cant state enough on how much better the truck drives, rides, and looks. Cant wait to take it to my local wheeling park to see how she does. A+ for CJC, they shipped it quick, and A++ on the quality that comes from Carli.
