Porposing on concrete highways, Bilstein worth the $

I don't understand how some on here say their shocks are shot at 12,000 miles. I have never had shocks go out that quickly. I think many of you just want to make an excuse for spending the money to the wifey. To each their own I guess. Your shocks should last at least 4x more than 12,000 miles.

I've been fighting rough ride for years now, previously on a 2005 ext cab Chevrolet 2500 and now a bit with my new rig below. The previous truck bucked badly on segmented highways when towing a TT.

Turns out I was running WAY too high of pressure with my tires. I consistently ran 75-80 psi which caused an awful ride. Now my pressures are set to the actual weight on the tires, not what the door placard says, this is especially true with aftermarket tires. I run 45 front, 35 rear when unloaded and 45 front, 55 rear when loaded.

These numbers came from my tire manufacturer according to their load tables.

Weigh your rig fully loaded, call your tire manufacturer for their recommended pressure.

Something to try.

I haven't been on the 294 bypass on the west side of chicago for a few years.

That particular stretch of road always caused my rig to do that

Only place I experienced it. :h

Along with the possibility of low tongue weight, is your WD hitch (bars) overrated for your trailer. in this case the WD bars will be trying to lift up on the rear of the truck because they are too heavy a bar. a properly setup hitch should no porpoise.

azdryheat wrote:

RCMAN46 wrote:
Have you ever weighed the trailer and TV. What is your tongue weight percentage? Is the trailer level? Low tongue weight and nose high can cause Porpoising.

Have you considered the placement of the axles on our trailers as the primary cause of chucking, porpoising? Our trailers are like teeter-totters in that they pivot about the axles, which causes the bouncing that we feel in the cab. Yes, we can control pin weight and load distribution but that doesn't offset the placement of the axles, which produce the teeter-tottering effect. I've found the cheapest "fix" is stiffer shocks and airbags to greatly dampen the bounce.

I agree with what you have stated. But I only indicated if the tongue weight is too low the trailer may porpoise. It does not cost anything to move all weight possible from the rear of a trailer to the front of the axles. With most trailers this is possible. Spare tires on rear bumper is a good example. Shocks and air bags will do nothing to help control sway.
I have a link that is very good about this whole problem.

An European take on towing

RCMAN46 wrote:
Have you ever weighed the trailer and TV. What is your tongue weight percentage? Is the trailer level? Low tongue weight and nose high can cause Porpoising.

Have you considered the placement of the axles on our trailers as the primary cause of chucking, porpoising? Our trailers are like teeter-totters in that they pivot about the axles, which causes the bouncing that we feel in the cab. Yes, we can control pin weight and load distribution but that doesn't offset the placement of the axles, which produce the teeter-tottering effect. I've found the cheapest "fix" is stiffer shocks and airbags to greatly dampen the bounce.

Thanks for all the helpful responses. Currently going to hold off on the new shocks, probably put on my Christmas list along with a power jack. Daddy has been a very good boy this year!

Putting shocks on the trailer will do nothing for controlling the movement while camping. You need solid support between the frame and ground and good chocks on the wheels for that kind of control. They will make the ride for the trailer itself much less bouncy when towing though.
Barney

This occurs on US 81 through South Dakota. Every time I drive that highway. The first time it occurred I was so concerned by it that I rebuilt the rear spring pack and new shocks all the way around. Then I went to the scale to ensure I had everything set correctly. Now that I have that information I know it is the road and there is little to nothing I can do about it. I have found since the suspension work and readjustments for weight that it isn't nearly as bad as it was and I can either slow down or speed up slightly to get it to a tolerable level. I have considered adding shocks to the TT because ours has leaf spring suspension. Might help with movement inside while camping.

I read about another person having the same problem on concrete highways. His solution was to increase the air pressure so that the tires would not act as an undampened spring. The theory is that the tires flex before the shocks. I tried it on mine and was surprised how much it helped.