I have a 1976 F-150 ranger. It has a 4" lift and 35" tires. It has coil springs in the front and leaf springs in the back. The shocks are in good shape, even the steering stabilizers. The problem is, the thing is beating the heck out of me when I take it up to the mountains. Someone suggested putting velvet ride shackles on the back leaf springs to "soften" the ride. Does anyone know about these things? Are they any good or a waste of money. In addition, does anyone have any suggestions about what I can do to make my ride smoother? Any advice would be greatly appreciated.

 

You should be grateful you have a 150 and not a 350, you might be expecting too much out of a full size D44 SAxle Truck. Velvet ride might soften the rear but you need to figure out if it is front jaring or rear hop that is bothering you before you through good money after an addition of that nature

https://www.ford-trucks.com/user_gallery/displaythumbnail.php?&photoid=4039&.jpg
https://www.ford-trucks.com/user_gallery/displaythumbnail.php?&photoid=474&.jpg

Why Buy new when you can build and tailor it cheaper?
F-350 4x4 ext cab Short Bed Green Monster, it is now Sporting a 300HP 715lb/ft Dyno rated 5.9L 12v Cummins diesel w/ NV4500 5spd and custom NP205 ford T-case w/ rear spicer 1410 yoke, Converted to Sterling 10.5 gears w/3.73 gears using the 41 spline pinion and 1410 U-Joints, Power-Lok equipt Dana 60 front, 33's on 16x8" Outlaw II's. (Used to have)205000 miles, Mass air 460 w/ performance heads and a E40d to 5spd conversion and Doug Thorleys. Old EFI 460 @10 MPG to the 12 V @ 23.2 MPG @ 75 MPH and loving it.
My other toy is a '69 CJ-5 354 Hemi 4 spd 4.88's 32x12.50 MThompsons w/ power-lok 44 rear.