Question for the suspension experts- lx450 chinook

[SWCruiser]

For those that don’t know I took a chinook pop up camper and grafted it to a chopped lx450. I’ve got OME mediums on the front and OME extra HD springs in the rear paired with Icon adjustable shocks on all corners. The rear springs are the heaviest spring available and I also run airbags. The rig is about 6900lbs. The combo seems to work well but the rear sags even with the bags. I don’t think they are overly compressed and I’m beginning to think maybe when I welded the frame to the camper body it wasn’t completely parallel to the rest of the body. I’ve contemplated moving to a slee 4” to raise the rear because I hate the sag. I also need more clearance in the rear as my tires are hitting the frame underneath. I think another inch or so would resolve that. My question is that if I do move to a 4” in the REAR only will I need more or less correction? I bought the slee caster plates and I’m hesitant to install them them as I don’t want to mess with DC drive shafts. I do need correction but may go the washer mod now instead. Any thoughts/ advice?

 

[mderrick]

I have caster plates on my 96' and am running OMEs I think you should be fine

 

[SWCruiser]

Did you have any issues with vibes?

 

[1973Guppie]

just a thought, have you considered switching to a leaf sprung suspension in the rear? works for heavy duty trucks that carry lots of load. It's going to be very stiff but you can get a custom spring to carry almost any weight.

 

[SWCruiser]

I haven’t considered leafs. I like the stock suspension setup and would like to retain it as much as possible. The rig isn’t much different than a fully armored rig. I’m just wondering if I raise the rear if I’ll need more or less caster correction

 

[shocktower]

I would look at different springs for different, vehicles that are a similar in diameter and length, or get a 6" spring and cut it down

 

[LINUS]

If the springs you install jack the butt up, then yes - it's possible you'll supposedly need more caster, but to a far less amount then when you lifted the front axle. You're not nearly changing caster needs as fast jacking the butt as drop/pivoting your FR axle.

I'm betting you may be fine but you might fall into the range of caster plates @NLXTACY vendors of Rick's.

They rotate the axle on the center of the inner driveshafts, rather than pivot on the rr axle bolt to your arms. Also, IIRC there are a few choices of * rotation for different lift heights.

The issue you would run into installing Slee plates vs Rick's is the little square notch you remove for Slee's would need to be welded back in for Rick's - so you have to be a decent welder or buy the weld work.

I chased getting my 4" lift to behave as close to factory neutral as I could get it, Rick's plates & a DC front shaft were what did that.

 

[LINUS]

Turkey coma afterthought - with that loaded ass & if you are flexing beyond the point a leaf spring rear isn't in your ideal setup, you may want the HD/longer RR lower arms.

Either make 'em yourself or again - Rick's got some premade via @NLXTACY .

When I did my 'return to neutral' kick / obsession on 4" springs, I bought Rick's math to build my own, he was instrumental in the dialing in what I wanted back w/ 4" Slee Heavies.

 

[SWCruiser]

Well I think the issue is that the rear is actually at about 2.5 to 3 now. I don’t think I’m overloaded rather that when I welded the support box for the chinook it wasn pertfectly level. So it looks like it’s sagging but maybe isn’t! I figured I’d raise the rear another inch or so and to get it level. I was trying to avoid the plates for a 4 inch lift.


Just saw that Rick has the plates for the 2.5. I think I’ll install those and see what 1 inch trim packers do. This is kind of a unique issue as it’s hard to tell how much lift I currently have. I know most measure the wheel well but I don’t have those on the rear.

 

[SWCruiser]

I haven’t installed the Slee plates yet! So no welding necessary but yes I can weld. May not be the prettiest.

 

[SWCruiser]

Here is a side view pic. It looks nearly parallel to the body lines but I think it’s slightly off

 

[Fj moneypit]

What about OME J springs or OME competition spings 2422/2423? Or a 30mm trim packer in the rear? You have bags already so not sure if you can do trim packer. Check @cruiseroutfit maybe he can help?

 

[LINUS]

The pic does look like the Chinook top does cant toward the rear.

Maybe the pic, but since you're seeing that in real life, I'd run a string to verify the amount you are out & shim the Chinook to get the body lines all parallel.

Then talk packers or stiffer coils, or bags, etc.

 

[Nay]

I wouldn’t worry about caster by adding a bit of lift in the rear, but as suggested above leaf springs are an obvious solution and how you would design that setup from scratch.

I know you aren’t looking for a redesign, just reinforcing a thought if you can’t get it dialed with the stock suspension.

 

[SWCruiser]

Thanks for the suggestions. I’ll get a string to it and get a measurement. But may just order the packers to see how it levels.