Hello all,

This is my first post. I am currently working on my 1996 F250 7.3. I am looking to revive the life out of this old truck and have done well so far. I have some suspension questions and have done quite a bit of research about potential RSK setups but need help in deciding what amount of lift and which springs to get in order to maintain or slightly lift the current level now... The plan is to tow a moderately sized fifth wheel to begin camping with my new small family until new truck prices and availability wont put me in the poorhouse. I have attached pictures showing the current suspension setup and D60 that originally came from a 1995 F350 that I parted out with 111K miles. Forgive my ignorance but here are my questions: TIA

1. Why do the spring shackles hit the frame rail?
2. What size lift is on it currently? I was thinking 6".
3. I currently have a pretty bad vibration on takeoff only when towing heavy, I was thinking only adding airbags to help this? Would prefer not to have ladder or traction bars. Pinion angles seem to be properly matched from diff and transmission tail, carrier bearing is also shimmed down.
4. What RSK lift amount and spring combo would I need to maintain the amount of lift currently?

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Are those 35's you have on there?

Might be worth shooting these pics over to Sky and PMF as well. They should be able to get in the ball park for a lift height considering they build the nicest RSK's out there.

I have a feeling the 2.5" PMF RSK with x code springs would get you very close to where you're at now.

 

Sorry I should have mentioned these are 37x12.50 17s.

 

Great looking truck vato. Have no input on your questions, but look forward to the revival of your truck.

 

I'm nowhere near a suspension expert, but some observations:
1) Your rear spring pack looks non-standard. More leafs than my 350. Looks like someone added leafs to stiffen it up and gain lift, rather than something approaching stock stiffness but more arch. If someone messed with the rear springs, well, they may have messed with the front...
2) Those front springs look too long eye-to-eye, and push the shackle forward into the frame. And with the positive arch, increased load will flatten the spring, increase the eye-to-eye distance, and push the shackle farther forward, or at least harder against the frame.
3) I did PMF's RSK on my 350, their minimum lift (2.25"?) and Superduty springs. I'm very happy with the ride and handling improvements. Only one thing I would do differently. I got the "heavy" crossbar with front 2" receiver, and got it powder-coated. If I did it again, I would not get powder-coat, then would do some welding mods and rattle-can it afterwards. The "heavy" crossbar is only like 1.25" square, much smaller than the crossbars on typical frame hitches, which look to be 2.25" or 2.5" square. I wouldn't load the front receiver heavy without some additional reinforcement. There is plenty of space to weld in additional plate or angle bracing, but that kind of kills the powder coat. Otherwise, very happy with the PMF setup.

I suspect you may be looking at new springs front and rear. Second the notion of calling the experts to identify your height and what options you have. How good are the carrier bearing, driveshaft U-joints, and spring eye and shackle bushings? Those could be your driveline shudder.