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I purchased a 2006 F150 2WD 146000 miles.
I replaced the drive shaft.
Rear brakes.
Balance and rotation of tires.

Trying to eliminate a bad vibration after 30 to 60 mph.
Worsening up to 60.

Took the truck to certified Ford today and was told its my leaf springs?
Badly flattened, truck was used for heavy pulling they claim?
Ford did full analysis motor and transmission with no red flags.

They say replacing the leaf springs will fix my problem $1500 for repairs.

I am so afraid I'm going to do this and I will still have the problem.
Any advice would be very appreciated.
Has anyone had this same problem? Weak or worn leaf springs causing a bad vibration?

Thank you

 

Long ways, a really L-O-N-G ways before I drop $1500 on leaf springs to cure a 30-60 mph vibration, I'm gonna check drive shaft for straightness, U joint integrity & proper phasing, tire balance, even rear parking brakes for releasing (happened to a cuzzes' truck, the p-brake cables being rusty were not letting brake shoes release fully .... they got hot and warped that drum part of the rear rotors).

 

After talking with Ford service department again it actually starts to make sense to me.
My leaf springs are almost so flattened seems if when I hit a bump or just drive it makes sense the driveshaft would make the PTO on the axle push down, that would cause some major vibration I would imagine.
There computer did not pick up any imbalance in the motor or transmission, so I am told.

And as I mentioned, I did all the above and then some.
Thank you for responding.

Bill

 

I found leafs online for $400, for both.
My local mechanic (two bay garage), will install them $300.

I am giving it a shot at $700.

I have nothing else to go on?

 

Before spending $$$ .... with parking brake fully released, get under the truck and wiggle all cables vigorously, make sure none are hanging up. Then go for a drive being careful to NOT use P-brake at any point.

My Cuzz's 06 had a similar vibration that started about 30 - 35 he said. , Ford garage & local shop failed to find it, I told him how to check it as I had been through a similar deal with a police car in the past after flood season due to rusty cables .... needed new rotors & emergency/park brake shoes.

Saved him some real $$$ for no costs.

 

They may be correct. If the springs are sagging such that the angle between the differential and driveshaft is not the same as the angle between the driveshaft and the transmission shaft at the front u-joint the driveshaft will vibrate due to the way u-joints are made. The u-joint angle at both ends of the driveshaft have to be the same to avoid driveshaft vibration. That is why CV joints are used in applications where the angles can't be always matched at both ends of the axle or drive shaft. If it were me, I would replace the springs. It appears the truck needs new springs anyway and I bet that willl fix your problem.

 

Isn't there supposed to be a vibration damper on that truck? if so, it may be missing.

 

IMHO, visit a local suspension/spring shop........ your springs may very well be able to be re-arched (hot, not cold process) and restored right back to oem specs

 

 

Before I'd spend any $'s; verify you have good tires and rims.
As for having overloaded (bad) springs, if the long (main) spring is the issue,
remove it and install a set of air ride bags (Firestone.)
I had basically the same issue and went the path of Air Bags (& never looked back.)
I keep the suspension up to get off the springs and enjoy the air ride (which is better than you will expect.)
AND; you can haul more weight too! Result: better towing capacity and a much better ride.
NOTE:I also added the Harley Davidson shock package to help with handling extra weight.
Most any HD shock will do this job.. pc