Some advice on a Chevy Suspension Upgrade

[booster]

First, let me say, most of this thread is way over my head but nevertheless has been very helpful. I need some final opinions, however. Here is our situation:

Suspension upgrades we have done so far to improve ride and handling (worked great!)

• Roadmaster steering stabilizer
• Bilsteins all around
• Sumo springs in rear.

These upgrades resulted in these current measurements (water tanks empty):

LF: 33 3/4"
RF: 33"
LB: 35 1/4"
RB: 36 1/4"

Minimum clearance at macerator = 6”.

Now we want more ground clearance! It appears the sumos have already lifted the rear a couple of inches.

So maybe we only need to replace the coil springs in front to level up the van? Not really needing adjustability of airbags anyway as our load doesn’t vary typically.

I would have ordered the Moog 81004, but recent posts suggest they have changed resulting in much more lift which would make our van not level requiring something to lift the back?

Also, one post suggests the the 81004 is only for diesel and we should be getting the 81008 for gas????

Or should I be considering the CargoMax springs at a great price from general?

Thanks in advance for all opinions!

The 81004 was the go to for a long time, but then went too high. They might be better by some now, but based on very little real information.

I don't recall any General spring installs, but may have missed one, so can't comment either way on that. Very many of the springs are all alike from the same place in China so might actually be the 81004 in a different box.

We have seen a couple of times that used the Super Springs version and got a bit higher than the old 81004 but not as high as the newer 81004. Expect to get 2.5" lift, I think. You don't want to go much over 36" high on the front wheelwells but good to get them more even than you have if possible. Much higher and you risk banging the upper control arm on the frame on big extensions of the spring.

There is also the option of using spring spacers that give about 2", but leave you with the kind of soft for the weight stock springs. Several places have them in aluminum which is what you want. Weldtec is a good source.

You can probably get taller Sumos, but IMO putting in airbags gives better results. Everybody had weight that varies due to fuel and tank levels. Airbags let you set the height in the midrange of the weight range, and even more allows you to even out the front wheelwell heights, which is more important the the rear is. You are an inch lower on the left rear than the right, which is typical as the Chevies tend to have more weight on that corner by several hundred pounds. If you bring up the left rear, it will push down the right front to even them out. The bags just need to be setup with two fill ports so you run more pressure on the left side.

I do think you should consider putting in a rear swaybar as mentioned in other discussions as I, and others, have found that to be probably near the top of how handling improvement you get. With a rear bar, you might be able to get rid of the steering stabilize which really is just a way to keep the driver from overshooting corrections in many cases as the corrections require too much steering wheel movement. The swaybar should reduce the size of the steering correction so smaller inputs needed.

 

[kimbpdx]

The 81004 was the go to for a long time, but then went too high. They might be better by some now, but based on very little real information.

I don't recall any General spring installs, but may have missed one, so can't comment either way on that. Very many of the springs are all alike from the same place in China so might actually be the 81004 in a different box.

We have seen a couple of times that used the Super Springs version and got a bit higher than the old 81004 but not as high as the newer 81004. Expect to get 2.5" lift, I think. You don't want to go much over 36" high on the front wheelwells but good to get them more even than you have if possible. Much higher and you risk banging the upper control arm on the frame on big extensions of the spring.

There is also the option of using spring spacers that give about 2", but leave you with the kind of soft for the weight stock springs. Several places have them in aluminum which is what you want. Weldtec is a good source.

You can probably get taller Sumos, but IMO putting in airbags gives better results. Everybody had weight that varies due to fuel and tank levels. Airbags let you set the height in the midrange of the weight range, and even more allows you to even out the front wheelwell heights, which is more important the the rear is. You are an inch lower on the left rear than the right, which is typical as the Chevies tend to have more weight on that corner by several hundred pounds. If you bring up the left rear, it will push down the right front to even them out. The bags just need to be setup with two fill ports so you run more pressure on the left side.

I do think you should consider putting in a rear swaybar as mentioned in other discussions as I, and others, have found that to be probably near the top of how handling improvement you get. With a rear bar, you might be able to get rid of the steering stabilize which really is just a way to keep the driver from overshooting corrections in many cases as the corrections require too much steering wheel movement. The swaybar should reduce the size of the steering correction so smaller inputs needed.

A followup: We installed the Moog 81008 along with front sumos. This disappointed us in terms of the lift - we only got about 1 3/4" of lift in the front. I wanted to post this so others know what results are likely with the 81008. We may consider spring spacers next, but are going to go with this for the time being. Our macerator and connections are now only 3/4" higher at 6 3/4" road clearance. :-(

 

[booster]

A followup: We installed the Moog 81008 along with front sumos. This disappointed us in terms of the lift - we only got about 1 3/4" of lift in the front. I wanted to post this so others know what results are likely with the 81008. We may consider spring spacers next, but are going to go with this for the time being. Our macerator and connections are now only 3/4" higher at 6 3/4" road clearance. :-(

I am surprised you even go that much. They must be a lot stiffer than they used to be, just like 81004s are.

If you install, the smallest that I know of, 2" spring spacer lift aluminum spacers, you probably will be too high and very close to hitting the upper control arms on the frame on drop bumps or dips when the spring control arms drop down.

Have you done anything to the rear yet? It appears not as the macerator didn't gain full 2" clearance. Our 15 year old 2" lift has settled to about 1 3/4" now and with air bags we still never hit the macerator. It is normal to have the rear about 1" higher at the wheelwells than the front so you might want to try that.