Ride while loaded

[ZR1Hauler]

I've done a lot of searches on ride quality. Most of the complaints are with unloaded trucks.

I've got an '01. Bilsteins & Michelins and a topper. It's got a very nice ride when unloaded.

My problem is when I hook up my 24' tag along race trailer. The ride is fine over slow moderate bumps. However it's the cracks in the road, expansion joints and any small thing that causes a fast movement in the suspension that just slamms the whole truck. After a 4-5 hour haul on any midwest road, we are just beat to death.

I may have too much tounge weight, but with some 1250 torsion bars, the truck sits nice and level, however the rear leaf stack is completely flat. It this my problem? We have tried different bars, different car position in the trailer, and even a killer air suspended hitch - but with hardly any difference in ride quality

Would a Kelderman help with loaded ride quality? Or should I try a firestone setup, and pump those things up until my rear leaf has a slight arch again.

Any input is greatly appreciated!

[Mudflap]

Check out www.activesuspension.com (http://www.activesuspension.com) I think they have what you need. I use their equipment with a 14,000 pound fiver, it works.

[mdadgar]

I have a Kelderman suspension on my truck and it helped quite a bit (I know exactly what you're talking about - I've got the same size trailer).

In hindsight, what I'd look at seriously in addition to the Kelderman is the new AirLift rear setup:

AirLift Suspension (http://www.airliftcompany.com/PrimaryAirWeb/index.htm)

The Kelderman guys are truly great people with the best customer service I've ever experienced. They now have a multi-link rear setup, too (not available when I bought mine).

Give 'em a call and chat.

- Mark
22' V-nose enclosed race trailer (4' V + 22' box)
'94 BMW 325is JP/A5 race car

[ZR1Hauler]

It might be tough to swing the additional $1500 for the full ride set-up (+ the extra install price) vs the original Kelderman air ride.

Is your towing ride acceptable now that you have the air ride, or do you feel that a full blown 4 link system is worth the extra $$ ?

It just seems like the original version is a really good deal.

Thanks for the advice

[mdadgar]

Yeah, it's definitely acceptable. It's funny - I was starting to think that it maybe wasn't worth the money after all. And then I rode in a friend's new '04 and my ride is WAY smoother. Particularly on concrete pavement, which gives the stock suspension fits.

Asphalt seems to be smooth regardless of suspension.

I think the combination of the Kelderman setup and Bilsteins is excellent, although I haven't pulled the trailer since I put the new shocks on.

But I still gotta wonder about a real multilink. smile.gif

- Mark

[biker Wayne]

I've been experimenting with my loaded ride for 2 years now. Concrete expansion joints would bounce us worse than an 18 wheeler. I've finally got it under control.
Here's what I've found. Some wheel bases are going to be worse than others. Mine is an extended cab long bed. Whats happening is when the front tires are going up over a joint, the rear tires are going down. When the front tires are going down, the rears are going up. Because of the timing, the front and rear axles set up harmonic resonance. Each is adding to the bump of the other. Put weight distribution bars on and you have another spring to bounce. You can try slowing down or speeding up to reduce some of the harmonic resonance, but you can only reduce it slightly.
Right now you're probably asking, How do I fix it? I'm glad you asked.
I pull a 9500# trailer with 1240# tongue weight. I did not have enough pressure on the weight distribution bars. The biggest cause of this was the slack in the shank going into the receiver and the slack of the WD bars going into the sockets (I've got an Equalizer hitch). I made shims to take the slack out of the shack and the WD bars in the sockets. It also helps to put on Bilstein or Rancho shocks.
Part of the problem is without enough pressure on the WD bars, the spring pack is going to ride too much on the bottom overload spring. The bottom spring is VERY STIFF! I installed AirLift air bags on the rear axle. This allows me to lift the spring pack off of the overload spring a little bit. The air bags ride MUCH smoother than the bottom overload springs.
We went camping this weekend and even my wife said the ride was greatly improved. She said it was comfortable. You couldn't tell we were pulling a trailer. She even fell asleep. The concrete expansion joints no longer make us sound funny when we talk. We also haul a 900# bike and a 400# bike loader in the bed of the truck.
Do some measurements. Measure from the ground to the top of the fender well on both the front and the rear. Then hook up the trailer. If the front measurement doesn't stay the same or go down, YOU DON'T HAVE ENOUGH PRESSURE ON THE WD BARS! The rear measurement should be 1 to 2 inches less. If its more than this, you need more pressure on the WD bars. In other words you need to add weight to the front axle. If not, you will have too much on the rear axle and the bottom overload spring will ride rough.
Hope this helps.

[Kennedy]

Here's what I have:

1 extra leaf in main pack. This improves ride both empty and loaded IMHO.

Bilsteins all 4 corners. Absolutely wonderful!

Air Lift bags in rear. Allows adjustment to spring rate to suit the load.


I've recently done exhaust work on a truck with Air Lift Primary Air suspension, and must say, the ride is NICE! It was a dually, and the ride empty was very similar to mine. The truck was still using the OE rear shocks as we work out the details on a special calibration Bilstein unit for the air ride.


P.S. the truck in question now sports a 5" tail WITH the air ride...

[ZR1Hauler]

biker wayne. thanks for the info. we'll try some airbags, it's definately on the overload spring, even with 1250 bars!

anyone done airlift with a Kelderman? man that would have to be the best thing next to a full air/4 link...

[mdadgar]

anyone done airlift with a Kelderman? man that would have to be the best thing next to a full air/4 link... Actually, yeah, someone here has. I spoke with him before I ordered my Kelderman setup, but now I cannot recall his name. He was very happy with the arrangement.

Hopefully he'll chime in here.

- Mark