Ford Explorer XLS
Ford F-150
The Difference Between

What would cause a 2000 f-150 to have vibration at 60 to 68 MPH the tires are new and have been balanced 3 times by two different shops?

User Avatar
Wiki User
2013-07-17 05:21:33

A simple wheel balance will cure most vibrations. But if that

doesn't cure the problem your problems may go deeper.

Inspect the rim--inside and outside--for any damage. Also look

at the tires--if you see any bulges or uneven wear of the tires,

consider them in the "probable cause" category.

Nothing obvious? Take the car for a test drive. When the

vibration occurs, is it while you're accelerating through a bend?

That means it's both torque and speed sensitive. When you pull back

to your garage, inspect the axle shafts, looking for damage to the

boots. Constant velocity joints can wear out. But if the boots are

intact, the clamps are holding them at each end, and there's been

no loss of lubricant and no intrusion of road film, then they're

probably in good condition.

If the vibration is not related to torque, shift into Neutral

and let the vehicle coast at the problem speed. Still have the

vibration? It's speed sensitive pure and simple. This could be the

source of your troubles, even if the wheels are balanced and the

tires are good. It's not a powertrain or driveline issue.

Jack up the front wheels by the control arms, so they're off the

ground, and support them with safety stands. Grasp each wheel,

holding it first at the sides, then at the top and bottom. See if

you can rock the wheel in and out and if you can feel any

looseness, which indicates a loose wheel or worn wheel hub

bearings. Wheel bearings (and the front bearings on many rear-drive

cars) are well-sealed and often are life-of-the-car without

lubrication. However, if you've been on a lot of secondary roads,

or glanced off a curb hard enough to bend a rim, they could be worn

or damaged.

Your Ford has adjustable front wheel bearings, and finding a lot

of free play in these is not surprising. To adjust, remove the

cotter pin, tighten the wheel bearing nut to about 20 ft.-lb. to

seat the bearings, and back off so they're just free but have so

little play that you really can't feel it. Then line up the slot in

the spindle with the nut and insert a new cotter pin.

You may not feel free play in a front wheel but try rocking it

in and out with a bit more effort, but not enough to move the

steering linkage. That could demonstrate free play from wear in the

tie-rod ends or ball joints. If you're not sure where the free play

is, pry up on the bottom of the tire and watch the ball joint to

see if it has free play1/4 in. is a lot.

To check a tie-rod end joint for looseness, try to flex it by

hand. A good tie-rod end should feel snug, but not immobile or

stiff.

On rack-and-pinion steering, it's a good idea to check the tie

rods' inner sockets. They're covered by the steering rack boots,

but you can squeeze the boots to hold the inner joint. Jack up the

front end to take the weight off the front wheels. Have a friend

slowly turn the steering wheel a partial turn to each side, while

you feel for looseness.

Just because you can't feel a lot of free play or "wobble" in a

wheel doesn't mean there isn't enough to cause vibration. It

doesn't take a lot to be responsible for objectionable vibration at

speeds of 60 to 70 mph and above any deviation from a truly

circular spin is called runout. It can be vertical (up-down) or

horizontal (in-out).

The only practical way to check for runoutfront or rearis with a

dial indicator, another tool you can rent at many parts stores.

There are several different checks to make to pinpoint the source

of the runout.

Mount the indicator on something heavy that won't move, such as

an anchor plate or wheel hub/knuckle. Position the plunger for the

specific runout check. Example: For a radial runout test, rest it

against a good tire tread groove. Slowly turn the tire and measure

the amount of runout, ignoring jumps in the plunger that result

from the shape of the tread or minor imperfections in it. If there

are factory specifications for runout, use those.

If you don't have specs, see if the runout is about .050 to .060

in. this measurement is considered rule of thumb. The tire almost

surely isn't the issue, although there is precision equipment that

can check a tire for heavy spots.

To isolate the source of the runout, check it at the wheel with

the plunger on an underside horizontal surface. Ignore minor

imperfections in the wheel finish (paint, weld, tiny dings) that

cause the plunger to jump instantaneously. If the runout is over

.045 in., the wheel should be replaced.

If radial runout isn't bad, check lateral runout with the

plunger against the sidewall, even if the in-out rocking didn't

show anything. Obviously, ignore any plunger movement from raised

lettering, etc. If the runout is over .045 in., it's too much. Here

again, isolate the runout by checking at the wheel with the plunger

against a vertical surface. The rule-of-thumb specs are the same as

for radial runout.

When the runout at the wheel is excessive, a new wheel normally

is the answer, but not always. Remove the wheel and check runout on

the wheel hub. Making a lateral runout check is an obvious

procedure because there's a hub face against which you can rest the

plunger.

For a radial check, it may be more difficult if the top surface

of the hub isn't reasonably smooth because you have to use the

threaded edges of the studs, and, typically, there are only four or

five of those studs. So it does take some careful measuring to see

if there's a significant amount. You have to look for the peak

reading at each stud to be sure you're measuring at the outermost

point. Unless almost all the radial runout is in the bolt circle,

and that amount is at least .030 in., go for a new wheel. Replacing

the hub and bearing on a front-drive is not a quick and easy

job.

It can take a couple of hours to check out the possible causes

of high-speed vibration, and you may be tempted to take the car in

for wheel alignment to see if that helps before you spend time on

all these other things. Sorry. Unless there's some evidence of

wheel misalignment (such as irregular tire wear), a wheel alignment

is not going to help at all. In fact, until you first isolate and

correct the cause of the vibration, alignment would be a waste of

time and money.

Additional Info.

I have found several cases of front end vibration due to worn

shocks and/or struts. These two items soak up vibrations caused by

oscillation in tires. No tire/wheel combination is perfectly

balanced. If he shock/strut is not optimal in it's functions, these

vibrations are transmitted to the steering wheel. Also when wheels

and tires are balanced, they are only balanced to themselves. Out

of round brake rotors and even slight loose ball joints may cause

the oroblem. If you front tires are the same as your rear tire

(which they should be) swap them and see if the problem still

exists. If it does, it is not a problem with the tire/wheel

combination. If it does remedy the problem, have the tires balanced

at a different shop first (worth the few bucks).

Additional Info:

It also matters whether the balance done was single-plane or

dual-plane (whether the balance technician eliminated only the 'up

and down' element of the tire/wheel imbalance, or the 'side to

side' element as well. It is common for many shops to use

single-plane balancing on alloy and custom rims so there are no

'unsightly' wheel weights on the outer side of the wheel.

A good balancing technician can use a computerized balancer to

minimize the amount of weight needed to balance a wheel. However,

many shops do not do this because it requires extra work

(tire/wheel must be broken down and shifted to accomplish this),

and often the technicians at big-box stores and similar venues do

not even know how.

There is a lot of very good, very detailed information in the

responses above. Just be assertive while checking the tire/wheel

balance element of your problem - you are the customer and any shop

that won't take the time to address your questions is not a shop to

which you want to take your business. ASK them to do a dual-plane

balance on your wheels, and if the amount of required weight is

excessive, to use their balancer's program to minimize the

weight.


Copyright © 2020 Multiply Media, LLC. All Rights Reserved. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply.