Rear end sag. Best fix?

[W7NB]

Like many others my 90 K5 has developed a saggy behind. It's only an inch or two, but it still looks like crud and probably doesn't help fuel economy any. The rig drives nice, and the current suspension setup is working ok for my 33/12.5's. I don't want to lift it anymore because I use it to tow my boat and haul stuff with and I don't want to haul a ladder to get stuff in and out

So question is just slap some 1 1/2 inch blocks on and call it good, or put in an offroad design 2 1/2 inch shackle flip and let the back end be a tad higher? Or go the extra and get a new set of springs? Thanks for the opinions!

 

[Muddytazz]

My opinion, you have 2 choices, new springs or the 2 1/2" shackle flip. If it was me I'd go with the flip

 

[muddybuddy]

could also do a zero-rate.

 

[UseYourBlinker]

It all depends on how much $$$ you want to spend.

 

[Muddytazz]

could also do a zero-rate.

Zero rate would work for an inch, but I wouldn't put a 2" zero rate under there even if it was bolted to the spring pack. Thats just me.

 

[W7NB]

If I go with the zero rates I probably will have to change the U bolts and if I'm going to do that I may as well do the U bolt flip while I've got it apart. Adds up to close to the cost of the shackle flip. I'm just not sure how warm and fuzzy I am with having to drop the fuel tank to do the flip. Anybody have experience with doing the flip have a comment?

I think I'll measure and see how low I am when I get home tonight. Perhaps the zero rates are the way to go.

 

[cbbr]

Dropping the tank is easy. 10 mins. The flip is a better option IMO. I run an ORD 4" and it is great.

 

[Chevy305]

I vote new springs...

 

[imiceman44]

Like many others my 90 K5 has developed a saggy behind. It's only an inch or two, but it still looks like crud and probably doesn't help fuel economy any. The rig drives nice, and the current suspension setup is working ok for my 33/12.5's. I don't want to lift it anymore because I use it to tow my boat and haul stuff with and I don't want to haul a ladder to get stuff in and out

So question is just slap some 1 1/2 inch blocks on and call it good, or put in an offroad design 2 1/2 inch shackle flip and let the back end be a tad higher? Or go the extra and get a new set of springs? Thanks for the opinions!

If you tow with it, I would put the air bags to lift it under load.
You can adjust the pressure for unloaded loaded so you will have the best of both worlds, soft suspension when you are unloaded and then stiffer when loaded.
I think the kit is around $200.

 

[W7NB]

If you tow with it, I would put the air bags to lift it under load.
You can adjust the pressure for unloaded loaded so you will have the best of both worlds, soft suspension when you are unloaded and then stiffer when loaded.
I think the kit is around $200.

Wow, Should have thought of that. I have air bags on my Dodge pickup for hauling the camper and towing, Does anybody know what airbags do to articualtion?

 

[muddybuddy]

Zero rate would work for an inch, but I wouldn't put a 2" zero rate under there even if it was bolted to the spring pack. Thats just me.

i agree, i thought he just wanted to fix 1" worth

 

[4xcrazy]

I added two more leaves to the spring pack, i drive a Burb, had a saggy rear, this leveled it out, and gives alittle more capacity for towing. It did firm up the rear end ride quality too, which in my case was a good thing, as those old stockers were allowing to much bounce and sway. Adding the springs will also help with towing weight capacity alittle as well.

 

[dyeager535]

Threw a set of 2" add a leaves into my stock saggy rear spring packs, sag was gone, cost was around $70.

Yeah, it might hurt ride quality, no clue how you'd know that on one of these trucks though.

 

[MattK]

Threw a set of 2" add a leaves into my stock saggy rear spring packs, sag was gone, cost was around $70.

Yeah, it might hurt ride quality, no clue how you'd know that on one of these trucks though.

how did the 0rates hurt ride quality?

 

[imiceman44]

how did the 0rates hurt ride quality?

He didn't use 0 rates, he used add a leave, which makes for a stiffer spring.
0 rate is just that, 0. Just a block that is bolted to the springs.

 

[4xcrazy]

I would think that adding "add-a-leafs" or the extra springs would actually put the rear suspension back to near "new" factory feel, as the 20-30 year old springs sag, they get weaker anyways, less spring. Adding the springs as i mentioned seemed to tighten up the rear end movement, and slightly stiffen things up to what seems more of a normal ride now, not so bouncy..

shouldn't really make it worse, just back to normal


Sheesh, that could all seriously be taken the wrong way

 

[MattK]

He didn't use 0 rates, he used add a leave, which makes for a stiffer spring.
0 rate is just that, 0. Just a block that is bolted to the springs.

im a dumbass

 

[imiceman44]

im a dumbass

No I am a smart-ass

 

[W7NB]

I think I'm going to go with the shackle flip. I got it on level ground yesterday and measured - about 2" low in back. I figure being 1/2 inch high in back won't be a big deal and I like the idea of the extra articulation. Thanks to all!

 

[jp0863]

my vote is swap to new springs, yours are old, in my opinion they should be replaced with new ones. there is a reason they sag, ask any spring shop and they'll tell you the same. they sag because they are fatigued. lets just say best case scenario there are no hairline cracks in them (which is far more common than you think), you are still dealing with old stretched metal which has lost its memory, which is why they are sagging. there is a spring shop here in my town and i stop in when i am in the area, you would be surprised what a 20 year old spring looks like magnafluxed (i think thats what they use)... scary to thing that people are driving on these things without any knowledge..... my advise, buy springs, then do airbags if you need. your money though!