New rear shocks causing bouncing while trailering?

[gixxer01]

Back in January I replaced the shocks in all 4 corners of my '05 Grand Cherokee with Bilstein 4600s. Saturday, we hooked up the boat and headed for Pool 4. Roughest dam ride ever! The Jeep would bounce so bad you could hear it in our voices while talking.

I experienced this once before when the surge brakes on the boat trailer didn't disengage, but I pulled over and checked and the hubs were cool. So, I have ruled that out.

Perhaps it was the road surface, but it seemed to do it even on smooth new roads.

The original shocks never gave me this bad of ride, and they had 200,000 miles on them. The Jeep used to pull like a dream, now just a rough beast.

Are the Bilsteins my problem, or is there something more going on?

[Jeremy airjer W]

I would bet it is the shock. To much shock for the ride you are looking for.

I have noticed that my vehicle does ride rougher with the TRD package which includes the Bilstein shocks Than similar models without the TRD package and the standard shocks.

The trade off, the Bilsteins will last a lifetime (in theory).

[gixxer01]

The ride was definitely rougher but smooth while not towing. Attach the boat and you would think the rear tires were squares.

You think the bilsteins would do that?

[delcecchi]

The stiffer shocks could be allowing the bumps to feed through to the boat. You hit a bump, it passes through the car and puts a push up into the couple/front of trailer. Front of trailer goes up. The momentum of the boat/trailer then pulls back of car up. Imagine what would happen with the trailer if shocks were solid and didn't move at all.

Softer shocks absorb more of the bump, and less movement gets fed through to the trailer.

Just my armchair analysis of a possible physics type explanation.

[RebelSS]

How's your hitch ball/receiver connection? Any slop? Check that, too. If your tires are aired up to the max,and you put on stiffer new shocks after having old, softer ones, you will notice it more, too.

[gixxer01]

Their is slop between the hitch and receiver. To be honest though, I think there is enough tougne weight to be a moot point. Even with the bouncing, I never heard any clunking from the receiver. And the only variable between the last two seasons of trailering is the shocks.

I understand your logic Del and think you're onto something.

Anyone know how I can return or resell these shocks. With less than 5000 miles on them, is it possible to return them? Is there a place to resell used car parts other than hsolist?

[Powerstroke]

I think Delcecchi was halfway there.

Stiffer new shocks mean your jeep doesn't sink down that small amount when the boat gets hooked up. Keeping that trailer tongue higher messes up the weigh balance and its too rigid to absorb the little bounce you're getting from the boat.

The only times I have experienced real bouncy trailering is when the trailer is not weighted properly and there is not enough tongue weight. When the weight of the trailer isn't being placed on the ball allowing the truck to carry some then the trailer is gonna move around any way it wants and the only control you have is the fact that you're pulling it forward.

A very easy way to test the theory of tongue weight would be to add some extra weight like a battery to the front of the boat or use a tow bar with a lower drop. You could borrow one from someone.

[leech~~]

I have had all 3 of these issues over the years that caused a trailering problem with a Jeep as well.

1) Trailer tires with flat spots from being parked all winter. One set was so bad I had to just replace them. Now every fall I jack up the trailer and put blocks under it so the tires are off the ground for the winter. Also check for bulges and delam spots on the tires.

2) To weak of shocks. The ride is kind of spongy with more of an out of control, swaying, hopping feeling. Scary ride!

3) Thought it would be cool to put on a set of Rancho's. The ride was very stiff and when hitting bumps it was more of a sharp jolting, spine hurting, teeth chattering painful ride. Had to replace them.

I'm think it maybe flat spots on your tires!

[gixxer01]

Hauled the boat down to pool 4 again yesterday with a buddies Silverado. Towed like a dream. I'll hook up to the Jeep again and see if the problem still exists. If so, I'll bite the bullet and buy direct from Mopar.

[ozzie]

it seems this isn't your issue since it towed fine with another vehicle but this spring my boat was jumping at low speeds while being towed and it ended up that the tires on the trailer were low on air...filled up the tires and the jumping has disappeared.