[Papa Rick]

I need your help and advice again. I had posted this question once before, and tried many things, but so far nothing has helped.

I have a 1985 Freightliner Day Cab, Spring Ride, the only shocks are on the front.

When going down the road at 43-50 & 62-70 my Truck has a bounce in it, not a vibration, but a bounce up and down in it.

You can not feel it in the Steering Wheel, the shifter shows no sign of going crazy at this time.

I put new steers on 20,000 miles ago, new shocks 10,000 miles ago, New brake drums on the front just last week.

Driveshaft redone completly.

The bounce gets worse the longer in the day I drive it. I haul logs for a living and when I first start out in the morning it still does this, but nothing compared to 12 hours later in the afternoon????

When I am coming to a stop it will buck and bounce like maybe I ran over something, not always, but more so later in the day.

I Noticed the Left front steer tire has what looks like a bouncing pattern in it where you can feel it with your hand just slightly?

The other steer tires were on the Truck when I bought it Sept 06, and had them replaced only 2 months later. They still looked brand new?? Took it to a Front End Shop to find out about the Vibration (VERY SMALL then compared to now)

The guy jacked up the front end and put it on a machine that spinned the wheel and man did it jump around.

He didn't know what caused this, but said that I needed new steer tires. They only do 3 axle alignment, no tire selling, so he was not just trying to make a buck.

Got the new steer tires put on, and no improvement?

After all of this, I am at a loss and really discouraged about finding the problem.

I have had some people tell me it could be a harmonic balancing problem, and I might agree with this, but it only had a small bounce when I first bought it, but now it is like riding a horse?

Any suggestions would be greatly appreciated, and if you know of anyone close to where I could take it, I am only 40 miles south of Chattanooga TN off of I 59 I would love to know, because I have had it in 6 different shops and most Mechanics look at this as a piece of Junk and don't really want to mess with it, but have no problem when it comes time to pay the bill.

It is an old truck, but has been took good care of, as I am the 4th Owner this Truck has had. It still has the Original Motor (Rebuilt of Course), and I would love to figure this out.

Sorry for the long post everyone, but this has really worn my endurance down much.

[cabbie313]

regarding bouncy ride on freightliner,had a problem like yours on a peterbilt.it would bounce like crazy when loaded,when empty was fine.did about all the things you did still had a bounce when loaded. finally got smart and checked fifth wheel for movement,had all kinds of up and down play in bushings. changed fifth wheel saddle and problem was cured. hope this helps you.

[Papa Rick]

Forgot to post, but this only does it empty. When loaded it rides very smooth, no bounce at all.

I have the same problem that I'm dealing with right now on my Western Star. It starts to happen after the truck has been driven a while. Sort of like maybe some rubber part needs to heat up before it starts. I also have replaced the drive shaft. I replaced my steers and all 6 shocks and no luck.

My problem happens at 55 to 60 but when loaded, doesn't happen till 70 or 75. I'll bet your problem is the same if you went faster when loaded.

I bought a cheap USB camera and already filmed the rear end but didn't see anything. As soon as I get the chance I'm going to film each front end part so I can at least narrow it down.

[Papa Rick]

Steve, could you explain in detail how to do the USB Camera, as I know very little about this, but would love to try this. It only does the bounce when empty. I have had it up to 80 loaded and it rides smooth.

If you have a laptop you can buy a cheap USB camera at Walmart. You will then need a USB extension cable from Radio Shack to reach into the engine compartment or rear of truck.

Tie wrap the camera to something so it's pointing at what you want to video.
The USB camera comes with video software. Bring up the video application and get it ready to go then start driving. When your ready, click on record with your laptop being in the passenger seat or have someone do it.

When you have recorded enough click stop then pull over and view the video to see if you can see the problem.

I would say keep doing this until you narrow down the area then start to focus on that area and get close it need be with the camera. They are cheap and worth destroying if it finds your problem.

[heavyhaulerss]

keep the bounce. it will keep you awake & alert. :lol:

[furbis]

I know you said the front shocks were fairley new but they could still be bad, when you park the truck at night after running all day feel each shock and see what the temp is if it is cold or very hot the shock is bad it should be warm, it sounds like your steers are starting to cup and I am pretty sure that is a sign of bad shocks. you might also grab a bar and see how much up and down play is in your 5th wheel.

My shocks were replaced and no difference. Although, that's a good point. Maybe the shocks aren't heavy enough for my truck? That would explain why it doesn't happen until things heat up like the oil in the shock. Something for me to think about and keep an eye on. Maybe time for some gas shocks if that's the problem.

[Bobby]

Rick,

If this truck has a heavy front axel (16K +) and Hendricson or rubber pad rear suspension ? what you are experiancing might be normal.