Quick Question...

I do a lot of driving from Phoenix to Los Angeles in my 2000 F250 Super Duty, Long Bed, Crew Cab 4x4. As soon as I hit those wonderful California freeways, the truck starts bouncing like a rubber ball. I have BFG 33's on the truck with stock suspension. Is there anything that can be done to improve this problem, besides throwing a bunch of weight in the bed?

Thanks.

 

You did not say if it was the front or rear that was bouncy,by putting weight in the rear I assume its the rear. What load range are the tires that you have. Sounds like the pressure is to low. I can't see the shocks being bad already but you never know. Try different pressures until you like the ride.

 

Thanks. You're correct, it is the rear, but the whole truck seems to bounce. I've notice other trucks doing the same thing so I don't think it's the pressure. I'm sure that it's the road and since I don't have enough influence to get Califonia Department of Transportation to smooth the roads out, I'm wondering if there is anything I can do to the suspension to reduce the bounce. I was going to try new shocks, but don't know if it's worth spending the money to try that and not have it do anything. I thought I'd check to see if anyone else has had this problem, whether in CA or any other state.

Thanks for the help.

 

Ford shocks are junk. I replaced mine(all were leaking) with Pro Comp shocks and think they are great. Nice firm ride but not too rough.

Les

 

I had to replace a shock at 2,000 mile because it was leaking. I was getting bump steer after installing a leveling kit, once they replaced it the problem was not as bad. If you have the PSD you will really have to get the correct shock because of the extra wieght in front.

In reguards to CA HWY's someone once told me that it is the expansion joints that make the ride really bad for trucks. I think that is to protect them from falling into the Pacific Ocean. ;-)

Rick

 

Spudwigley,

I understand exactly what you are talking about. I have a '99 F350,CC, Longbed, 4x4. I live in the Sacramento area and we have many of the freeways around here that cause the bounce you are talking about. I believe the reason why the Superduty trucks (maybe other 3/4 and 1 ton trucks, I don't know) bounce so much is the expantion joints are at just the right distance apart that as the front and rear tires hit them a mechanical resonance is created in the suspention. This happens with my truck between 60 and 70 mph approximatly. If I go slower or faster the bounce lessons and then goes away. My truck bounces front and rear.

For those of you who aren't familiar with mechanical resonance, it is the natural frequency that (in the suspention for example) the springs and their asociated components will compress and then extend if initially compressed and then released abruptly. As you drive over the joints in the highway, the distance the joints are separated and the wheel base of the truck combine to allow the joint or "bump" to push the front and rear tire/spring upward at the same rate the spring would naturally bounce back from being extended. This "adds" energy to the spring's "bounce". Combine the front bounce with the rear bounce and my truck acts like a bucking bronco. It's just a matter of timing. The shorter wheelbase Superduties may not have this problem as much because the tires hit the joints at differnent positions, front vs. back. Or if they do it would most likely be at a differnt speed than that of the longer wheelbases. If you experience this bounce in just the rear or just the front the same logic applies but you probably have very different spring geometries, front vs. back.

Sorry for the long winded explanation. As to what would help, I would imagine shocks would help the most. I've been contemplating changing my shocks. Tire pressure may help, I haven't tried it but I wouldn't think it would help too much as the joint bumps are quite large. If anyone comes up with a fix let us know!

 

Thanks man! I feel so validated! Phew! I'm not the only one!

Anyway, the info was great. I think I'll try some new shocks and see what happens.

Thanks again for the info.

 

This is one reason I love my Rancho RS9000 shocks. They are adjustable, so you can tweak the dampening to suit your taste in ride quality. Check www.gorancho.com for more info.

----------------------------------------
2000 F350 CC DRW Lariat 4x4 LWB 4R100 V10 4.30ls with Torklift tie-downs/Superhitch and Rancho RS9000 and Ride-Rite air springs.
1998 Alpenlite Pendelton 11'10" Slide-in camper with all options.

 

It's the California Freeways! With little weight in the back of trucks, any bump makes the suspension worse. It's the older freways which are the worst. They cut expansion joints as to counteract the expansion that occurs to the California Freeways in the bitterly cold winters here, 50F. (Just being sarcastic).
To tell you the truth, I can't tell you why they cut expansion joints on highways in Califronia. They don't stop the cracks from growing. All they do, in time, is create sections where the section edges rise (expand) upwards and cause the severe bumbing. Therefore, the need for the kidnay belt or the "spine imobilizing cusion" which needs developing.
There's been lots of freeway "shaving" done in the last year. That's where a machine cuts down the bumps in the road and creates a much smoother ride. If you're ever in Southern California and you want to experience the ride, try Interstate 10. And don't forget the cusion and don't bring the children. You may be accused of 'shaken baby syndrome'.
I remember when constructing a highway meant two things: get them straight and get them flat. Not much to learn in enginnering school is it?

 

https://www.ford-trucks.com/dcforum/User_files/mil1ion/3bd616b574634ddc.gif
Have you noticed this on ALL CA roads or just the ones made out of concrete ?
It is a well Known Fact that Concrete roads make BIG trucks Bounce.
I worked in EVERY aspect of the Concrete business.
When I drove a mixer/truck ,Bouncing is a Bonus Ride.


Dennis

Dennis

78 F-150 429CJ 465,000 KM.(Original Owner)
68 Mustang 289 Sunlit Gold 80,000 Miles(second Owner)
64 1/2,260 Pre-World's Fair Mustang #8092
64 Fairlane 500 S/C,waiting for a 390 4-Spd

If The Girls Don't Find You Handsome,
They Should At Least Find You Handy!

 

It's the concrete highways that do it. I'd swear that the California Depatment of Transportation and the neck brace industry are owned by the same people.

 

I have the same problem, but to a lesser degree. But as I like to travel in the truck and rarely have heavy load in the bed I want to help this problem.
I have a 2001 F250 4x4 with V10 CCLB. And I have Rancho RS9000's, F350 4" rear blocks and a Pro-Comp 4" lift, Which rides very nice. But the Truck does ride much nicer when I have a motorcycle or two in the rear.
Another owner on this board has a similar lift but also has Velvet ride shackels and he says they are a noticeable improvement.
I will likey order a set this week and I let you know how it works out. Here i the link FYI.
http://www.velvet-ride.com/

William Ow
Santa Cruz, Ca
2001 F250 4x4 CCLB
Pro-Comp 4" lift, F350 4" blocks
Rancho RS9000 Shocks, American Racing 16x10" rims
Pro-Comp 315 tires.

 

I'll have to try that. I guess it's time for new shocks anyway.

So what kind of bike(s) are you putting in the back of your truck?

 

 

I drive the freeways quite a bit in Los Angeles. I had the same problem. After reading your thread, I tried tire pressure of 32 front, 38 rear, and the problem almost dissapeared, even with an empty bed. My truck has 80K mi with stock shocks.

I think the gentelman that commented about harmonic vibration is correct, and the different tire pressures cancel each other out from front to rear.

Just my experience, and it's free!!!