I'm trying to get my 1500 dmax to ride better. Front is too soft, rear is too stiff. I have not weighed the front and rear independently, but I'm assuming that adding a couple hundred extra pounds for the Duramax/Allison combo threw off the weight distribution of the truck.

The front of the truck is too soft right now, has too much bounce/oscillation when hitting dips and stuff like that on the road, and I frequently bottom out the suspension when dropping down off a speed bump. I ordered some Rancho RS9000XL adjustable shocks to try and firm it up a little.

The rear of the truck is too stiff. When I hit things like expansion joints in the freeway, I get a slight shudder going through the whole truck. It only happens when the rear goes over the bump, not the front. I have stock leaf springs with the overload removed and Caltracs, and Belltech Street Performer shocks. There's negative preload on the Caltracs (probably a 1/2" or so gap between the roller and spring), so I don't think those are causing any issues. Does this sound like a shock issue or spring issue? Softer shocks are an option but I don't want to spend the money on them if they won't help. If it is the springs, can I pull the bottom leaf out, and maybe put the overloads back in so it doesn't affect the ride height? Any ideas?

 

Since you used a 1500 4x4 Chassis, How did you equip the suspension?

Are you running 1500 Torsion bars or the 2500 torsion bars?

 

it's all stock 1500 suspension.

 

I'd swap in the 2500 torsion bars and get the adjustable shocks on. It should smooth out pretty easy like that. I bet your rear shocks are shot...

 

All torsion bars have different spring rates for each application.

I would see if you could locate some torsion bars from a regular cab long bed diesel 2500 as it would be the closest to your combo.

 

I'm actually more worried about the rear than the front. I think the new shocks will take care of the soft front end. I'm not so sure they will help the rear, that's why I'm curious if I will need to mess with the springs. I'll probably test it out by pulling the rear shocks out to see if that softens things up and go from there.

 

Roger, the fronts might be shot, I bought them used. The rears I bought new. They only have 12k on them.

 

Belltech SP shocks are garbage...

Chris, I can't remember, did you already remove the rear axle bump-stop bracket & bolt the bump-stop directly to the frame? I think you did already, just can't remember...

Mount a go pro, and take a test drive. I bet your rear shocks are not controlling the rear axle.

 

Those Rancho RS9000XL suck! To soft even on their stiffest setting. The adjustment is only on rebound as far as I can tell. You can have mine if you want them, lol. I just took them off and put QA1 single adjustable on my truck with Atomic's coil over deals on the front with 1200lbs springs and normal QA1's on the back and ride is SO much better!!!

 

Yeah the bracket is long gone. I've read mixed reviews on the SP shocks lately. Be nice to try something new.