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FunSocalTiger --

I have only run that stretch of highway once this year and didn't notice anything unusual. But, I have a reg cab short bed and I was pulling a trailer at the time.

I think it has to do with the spacing of expansion joints that Cal Trans puts in the highway. I had the same thing happen to me in my '86 crew cab on a stretch of the 60 freeway out towards Riverside. It is a harmonic vibration sort of thing. When you are traveling at just the right speed the combination of your front and rear tires hitting the expansion joints at just the right frequency causes your truck to start bouncing. It can get quite violent and very irritating for sure. I just tried to take a different route. Heavy duty Rancho shocks didn't help.

Good luck and get a firm grip on the steering wheel.

 

I have not been on that stretch of highway in my truck but the same thing happens to me on the 405 near the 22 in south L.A. Co. /north O.C.. My truck is basically the same as yours, but is a '99' Flareside.

Jim A

 

Hi Jim A --

Yeah, I think you might even notice it more in the summer time when it's warmer. The roadway expands in the hot weather and the joints buckle a tad. Over the years, I am sure that earthquakes have probably played a part in the expansion joints becoming misaligned too.

I never really noticed this anywhere else but in SoCal. I'm sure it must happen other places too.

 

The reason your truck does that on that highway is because the joints on the roadway are spaced the same as your wheel base. Its been addressed on the boards before. this causes your truck to "hobbyhorse" if you will. lol.

 

It is bound to not be as severe if you slowed down a bit, but would that keep you from getting run over?

 

Eduk8er,

If you slow down in So. Cal. you get your a$$ run over even in a F-150. Today I was out riding my bike was going 75 to 90 and even 100 at times and being passed left and right.
Jim A

 

Yeah, even driving 65 on a lot of freeways can be extemely slow depending on traffic. I find that whether I'm going 70, 80 or 90 there are always people going as fast and faster as me.

And thank you for all your responses. I also went in and asked one of the guys in the service department and before I finished my question he knew right away what I was talking about. FYI, he told me Ford is planning on releasing a fix for it around next summer or so. He said a redesigned bumper to dampen the bouncing? I didnt quite understand how a bumper could dampen things, but just left it at that. He said a TSB would be released when it happens.

Laurence

 

Hi all I've been living with this problem for a few years now with my '98, I have the extended cab and tow package,I get the hell bounced out of me around Seal Beach and 5 at Crown Valley,I've placed 2 90LBS.sacks of concrete in the bed and that helped just a little.Called ford and talked one of the mechanics,he told me he had the same problem with his truck and that he went with different tires to correct the problem.Who knows,I still have the Generals on mine,I'll call a few more Ford places nex weekend.

 

Hmmm I have the factory sport wheels which have the 275/60-17 tires... arent those bigger and wider than 90% of the F150 wheels? So if wheels help then I cant imagine how bad it is for the f-150s with the slimmer 15" wheels.

I have noticed though that it doesnt bounce nearly as much when I have a load. I was moving the other weekend and had maybe 200 odd lbs of stuff and it seemed to help. Maybe buying a tonneau cover would help since it weighs around 200 from what I've heard...

Laurence

 

Hi,

 

Hi,

I joined this forum specifically to look into this same problem with my new(ish) SuperCrew. Problem only occurs on some concrete pavement and I also believe it has to do with spacing of the pavement expansion joints, but it is truely a FORD problem. I had a company owned Windstar that did the same thing but the vibration was up front. On the other hand neither my old Tundra nor my friends Tahoe do it on the sections of freeway that give me the most problem.

My brother-in-law had the same problem with his Explorer and was able to minimize it by careful balancing of the tires. A full load (more than 200 lbs) will smooth out the ride and as with an earlier posting I tried sand bags with only so so results. I was going to try playing with the shocks but that will be a pretty expensive experiment so if anyone has any better solultion I'd love to hear it.

 

As has already been mentioned, you have a harmonic vibration triggered by the spaceing of the expansion joints in the freeway, and the wheelbase of your truck. I have driven the stretch you mention, a number of times, however I have an Expedition, much shorter wheelbase, and have not noticed. Of possible interest, and because I've been around for a long time, in 1959 and 1960 the Cadillacs of the day did the same thing on a stretch of what is now I-5 southbound between Los Angeles and Santa Anna. It was so bad that at certain speeds the cars would literally hop from lane to lane, could not keep the wheels on the ground. Those cars, of course had very soft suspension. You learned to stay away from those cars if you saw one nearby on that stretch of freeway! It was quite entertaining to watch.

 

Can't be a bumper, he must mean shocks, or ????

 

Yeah I'm pretty convinced I heard him wrong. But I swear that's what he said. But that doesnt make sense unless maybe the new bumper is 200lbs so as to increase the rear axle load. But why would they do that just to smooth out the ride? But it can't be the shocks either because I've heard aftermarket shocks only marginally help this problem. Who knows... I'll go back to them 3-4 months from now and ask them again...

Laurence