springs loosing height

[PGSigns]

I drive my 66 almost every day and it is developing a tire rub in the front over time while turning. It has CPP 2" drop springs with 2 1/2" drop spindles and in the last 20,000 miles (18 months) has lost best I can tell just over and inch. Now it sets an 1 1/8 off the factory bumb stops. The rub seems to be getting worse over the last few months and is now a problem when turning right into some parking lots. I think the springs are toast and need swapped. What do yall think?
Jimmy

[The Rocknrod]

I think the springs settled as they do normally.

[PGSigns]

I have had them settle in the first few thousand miles but not continue to settle over two years. What bothers me is it continues to drop like the springs are loosing the temper and going soft like a valve spring does. I put 20000 miles or more on these springs and they were in the truck for several thousand miles when I got it.
Jimmy

[Kenfuzed]

I realize this is many months old but I was wondering if you ever figured out the issue with the springs losing height or slowly compressing. I'm preparing to install a set of 2.5 drop spindles and need to know if installing a set of 2" springs will result in the same.

[PGSigns]

They seemed to have settled out. I also found I had two places the tires were rubbing. The front was not the only spot. Fixed it with a tweek to the fender. I also had a rear tire touching the wheel well when in a tight turn like entering a driveway with a good bit of angle change that twisted the truck some. I did a check of the centering of the rear end to the frame and it was pretty close. The bed does sit a little to that side. The CPP springs are a pretty soft rate and seemed to have lost a little rate over time. I think this contributed to the settling in the front and progressive rub in the rear. I loosened the bolts on the bed and shoved it over jut a bit and added an 1/8" to the panhard bard adjustment and that eased it up. Still will rub some on certain driveways but not near as bad as it was. I bought a set of 6" Hotchkis springs with the 1/2" spacers for the rear to replace the 3" springs and the 1 1/4 blocks and to level the truck out some more but with the move this summer never got them installed. The truck has 15X8" wheels front and back with 4" of back spacing. I think with a different tire and wheel combo I would have never noticed it. I also drive my truck everyday and put a lot of miles on it. It gets used to haul stuff and the springs get a work out. Had enough salt treated lumber in it the other day to drop the truck to dead level. Had to be more than a thousand pounds in it. Was an inch lower than with the road king in the back.
Jimmy

[Kenfuzed]

Hey Jimmy thanks for that info. The PO installed CPP 5" rear coils and there's less than an inch between the uncut bump stops and where they hit the U bolts. I will probably cut 2" off the stops to regain some travel but don't want to hack them all the way off since I don't want to slam an axle tube into the frame when I hit the next bump. The springs are about 5 years old but they really haven't had much of a workout since it's a shortbed and my 900 lb Streetglide wouldn't fit in there anyhow.

The truck currently sits 6" lower in the back than stock height so perhaps the springs have already settled. Depending on where my new drop spindles and drop coils (2.5 + 2) leave the front I may also need to add blocks in the back to get the level I prefer. New bigger wheels/tires will be here in 2 weeks so I'll see then if I encounter any rubbing in the wells... fingers crossed.

[PGSigns]

Look at the traction bar bumpers from Mr Gasket. They are a good bit shorter and not hard as a rock. You can drill a 3/8 hole and line them up so they hit the axle tube.
Jimmy