I'll add my vote to the 500 lbs making a world of difference.

 

100% agree here.

My truck rides terrible when empty. I have the 45mph oscillation, bump steer, and bone jarring ride.

Thing is, the chassis is engineered to be safe with lots and lots of weight on it. Trailers and cargo is supposed to be the normal condition.

I'm betting that ford designed the trucks to operate loaded. Everything is working right when it's loaded down, the unloaded truck is "out of spec" if you will.

An unloaded truck, and an overloaded truck are both expected to have undesirable conditions. Right in the middle is the way the truck is supposed to be.

When your truck is overloaded, you expect and accept things that aren't quite right. Poor performance, strange ride, all that stuff we know about. Riding unloaded is the very same. It's outside of the normal operating range.

 

Just adding my experience. I have a 2012 F350 4x4 Lariat PSD, 4 door short bed with 3.55 rear and 20" wheels. I have 2,000 miles on it so not much driving yet. No bounce or vibration noticed. I drive between 40 and 50mph much of the time and so far it rides great. Hope I don't develop the bounce later. So far so good though.

 

I am new to this Form & have just picked up a 2012 F350 Long bed CC, 4x4 and am trying to to determine the "rear end bounce" verses "harmonic vibration", is this the same thing and or am I missing something?
I believe I have the 2nd one and it comes on at roughly 1400 RPM @ 35 to 45 mph range and is at the dealer now with 620 miles on it & they have a call out to Ford.
So to the people that have this issue does it get worse as the odometer go up or is it the same all the time? Thank you for your time.

 

My 2008 Ford F250 6.4 20" wheels rode great empty or loaded and did not have the 45mph hop. I think there must have been a change to the steel, the frame, or other components that added the harmonic vibration back into the equation for the '11 and up Super Duties. Alot of the guys that own the pre '08 SuperDuties have complained about a similar hop.

I no longer have my F350 4x4 CC Lariat 6.7. Some days I wish I had it back, hop and all. It was a great truck other than that dang hop. All the roads around here are basically 45mph because of urban sprawl and the hop was with me day after day.

With all the complaints and warranty work that Ford has spent with dealers since 2010 on the '11 model year and up to try and correct a non correctable vibration problem, I bet the next Super Duty version will ride like glass both loaded and unloaded. Until then, I don't think there is a cure.

 

I was following a new model F250 the other day and noticed the bed rails looked like they were vibrating quite a bit in rapid motion. Might have been this phenomenon you all are describing. I have to wonder if this is a vibration that is resonating from frame to bed and making it shake like that.
Has anyone thought to try and put some criss cross straps from corner to corner in the bed and do another test drive? Like stakes in each corner pocket and then strap them across to each other diagonally and see if that might suppress the vibration...just a weird thought I had as I was seeing this first hand when following at this speed.

 

So Ford had a fix, they replaced the driveline after the dealership had it 6 days.
It helped however it still has the what I will call a harmonic vibration, can anyone answer if it gets worse over time? If so the dealer will have this truck for a while. Thanks

 

Just joined the forum today. Bought my '12 350 King Ranch LB diesel Dec. 22nd. Lots of vibration at 40+ mph and "bump steering" issues. Dealer, re-aligned and force balanced the 20" Michelins, remounted all 4 wheels and problem was minimized (not 100%), all within the first 2 weeks of buying (less than 1000 miles, no hassle, yea!). Bought a '12 Destiny 5th wheel (355RE) in Salt Lake City on Jan. 17th. Going over, averaged 20.8 mpg via US50/I70 @ 75-80 mph! Happy, happy! The trailer (claimed empty wt. 11,880) was hooked up and we took off for home. Immediately, under load, a severe take off vibration was present that I knew was driveline related. Once it was moving above 10 mph, it smoothed out. Pulled Soldier Summit, Cerro Summit, Monarch Pass (11,880') like they were almost flat. Amazing, 4th gear - 1700 rpm, so much power (-5 F, v. cold). Coming off the passes, engine brake in 3rd held the rig to 40 or under with minimal braking required. Man, am I ever happy! Once home, took the rig into the dealer with complaint on the "under load" vibration. (I once had a '86 E-250 pulling a small TT and had the same issue with vibration starting out. Ford replace the 2 piece driveline with a monster single piece driveline, problem solved.) Again, dealer was on it like I was their only customer. They contacted Ford, once they were convinced I was not exceeding GVW, etc., authorized complete replacement of the driveline, yoke to yoke. Part No. BC3Z-4R602-MP. Parts came in 1 day and work done on Jan. 23rd in less than 4 hours. Absolutely corrected all the problems, including the (empty) original issues with vibration. The carrier bearing housing was also replaced, much beefier looking. For information, don't trust the name plate wts on the trailer. I weighed the complete rig and then the truck. The trailer is actually 14,080#, empty. The truck is 8420#, w/3/4 fuel and 5th wheel hitch (no pass). And lastly, with gross wt. around 23,000# coming back from SLC, I averaged 13.8 mpg, mostly at 60-65 mph, to Colo. Spgs. Sorry for being wordy, but my faith in Ford continues to be reinforced with performance and results. Pictures to follow once I learn how.

 

Congrats on the new truck and welcome to FTE!

Glad you have good things to say on your first post. Most of us wound up here with questions about why this did that? I too have the rear end shutter you speak of. FOMOCO replaced the third member in my truck with a new one and it still does it. After 30,000 miles and 12,000+ of that towing my 5er, I quit worrying about it. Some say axle wrap is the cause. I can see the logic in that. Some say driveline angle is the culprit. I can see that too. Airbags have had favorable results for some while others have said they didn't work. I just ease off the line when I'm strapped to somethin heavy. I weigh in a little north of 29,000 when all loaded up. Dually handles it like a dream.

There is a post in the tech folder at the top of this forum page 1 that explains how to post pix. It's fairly easy once you learn how. There are a couple different ways to do it. A lot of use Photobucket. It's a web based hosting site.

Again, welcome aboard.

 

Just joined tonight, have read all 25 pages and was hoping someone had an answer to this issue. I have a 03 F250 crew and i have the same problems. mine start at 42 and smooth out about 47. Im a honda master tech and these big trucks are way out of my league. i have changed tires to a 285/70r17 and balanced more times than i can count. I bought the truck with 60k on it and it wasnt doing it then, i now have 95k on it. over the 4 years i have owned it it has slowly gotten worse. I was hoping the drive shaft replacement was going to fix your problem but am discouraged by fords response. When they say ( thats the nature of the beast ) is a total lie. That means that the dealership wont spend anymore time on it because they are not getting paid anymore to fix it. Warranty time is a joke anyway. From the looks of this problem it spans a huge number of years and would have fixed this issue early on in the production years. Im going to try a few things on my truck now that its paid for. i will leave my results in future postings. I forgot to put info in. Ford just completly rebuilt my rear end. The problem is still there, so dont have them rebuild rear end. My limited slip went out due to a leaking pinion seal, that wasnt anything they suggested for the hop. Just wanted to add the info of the overhaul and i still have the hop issue.

 

After owning my truck for 2 years now, I think that I have figured it out.
It comes from the design of the rear leaf springs. The bounce only happens when unloaded. Once you put weight in the bed the leaf springs stack together against each other and it does not bounce. I have air bags on mine. I tryed inflating them while the truck was unloaded to see what would happen. The bounce went away. This is because the spring was unloaded due to the airbags holding up the truck. That was not practical because the rear end sat too high. I installed a set of the adjustble Rancho 9000 shocks and tried several different settings. The harder the shock setting the less bounce. I think that is your best solution, get adjusable shocks and keep turning them to the firmer setting until it goes away.

 

I don't have the issue on my trucks, but I run a taller block, airbags and non stock shocks. That being said, this post makes a lot of sense to me. I think he is on to something for you guys having rear end hop issues. A set of progress rate springs might fix this issue. You don't have to go to a Carli pin-top 2.5 system. A set of Helwig progressive helper springs might solve (help) this issue:

 

The problem is caused by the springs being made longer when Ford re-designed the trucks either in 1999 or 2003. My 1994 F350 had much shorter leafs. On the new trucks when unloaded, the one longest leaf is the only one holding the truck up. The other shorter leaf springs are not touching each other. The one long spring is so long that it easily goes into an occillation. This goes away when loaded because the leaf springs stack up together. The re-design with the longer main leaf spring was an attempt to improve off road ride quality, and it worked. My 2011 rides much better than my 1994 did. Unfortunately the side effect of the longer spring is this occillation. I don't believe that added helper springs would solve the problem because they would be un-loaded (not effective) when the truck is empty.

 

I have an '08 F250 SD Long bed, super cab. This bounce has just started at 70k miles. Immediately after the first set of new tires. So, I blamed the tires. I purchased new tires from a Ford dealer. 2 on the front in October '12, 2 more on the front in February '13, with the original 2 moved to the back. I had Continental Contitracs originally. Had planned to replace with the same after having such great ride and mileage from them. However. let the dealer convince me to go with Michelin. The hop began immediately after getting the 2nd two tires. I went to the dealer, (where I was treated like a one night stand returning to report I was pregnant) They test drove, rebalanced, rode with me while I test drove. No solution. Agreed to drive for a few days. Drove 80 miles across secondary roads, and by the time I got to my destination, I was irate, and with a headache, that actually hurt from the 2 hour bounce. I went to a tire dealer I trusted, they returned to the showroom snickering at who had previously balanced them, and proceeded to correct the balance in all 4. This did not help. I contacted Michelin, found an Authorized Michelin dealer to access the problem. Discount tire, was very thorough in balancing them, and they also scoffed at who had previously balance the tires. They road forced and actually rotated two tires on the rims. This did not help. They suggested replacing one suspect tire, then a 2nd suspect tire. But I held off. I took the original spare and rotated it all around the truck to try to identify a bad tire. No luck. I did think that no matter where the Continental was, it seemed to improve the bounce. So I took the opinion that the Michelin's would not work on this truck. I went back to the authorized dealer, (who didnt treat me like a red headed step child. Yet) and they gather all the data, contacted Michelin, replaced them all with the same type of Michelins, snookered me out of $150 for "certificates" plus the expected $64 for their time and work. No good. However, It did help identify that the bounce was between 35 and 45 mph. That is what led me to this thread. I will add one side note I found interesting. Besides each shop finding the previous shop's balancing was out, even 1 shop re-balancing their own work, each shop, even Michelin customer service, had a different tire pressure recommendation. All different than the door sticker.

All that said, I still am not sure sure it is not the tires, and had really hoped to be able to put the original Continental on to be sure. The Michelins are definitely a rougher ride, and could be just enough to set this problem off.

Of all the Ford dealers I have tried, there may be two that have enough experience and concern, that I may bring this to them to see what they can come up with.

 

^ no takers yet i see guys?
added benefit to possibly curing your hop issues,is that she'll set up and take the loads much nicer for ya too.so lets say it doesn't fix the hop,you'll still have a nice stance while loaded without the air bags.so you won't be out either way.