OK guys, lets see if I can get some info. On my 04 STX 4X4, with the 4 wheel drive engaged and above 35mph, i get a whining, whistling type of noise, but I can't tell if it is from the hubs, transfer case, or the tranny.....Any ideas????? Thanks in advance!!

 

Is this your 1st 4x4?

The t-case noise is normal.

In a 4x4 the front axles are turning faster than your rear causing a little gear binding. This allows you to be able to steer and pull through in sloppy or icey conditions.

In an all-wheel drive the front and rear axle turn at the same speed making turning in icey or sloppy condtions near impossible. All wheel drive was designed for dry conditions to get better traction for racing.

You have a 4x4...it will make noise.......caution: try not to drive on asphalt for extended distances while engaged in 4x4.....very important in 4X4 LOW gear.

 

nope not my first 4X4, asked 2 of my brothers and my dad, both had ford 4X4 pickups, and all of them said the noise was not normal. I am familiar with the driving dynamics of a 4 wheel drive system(bucking and other items) and I know only to use 4 low for low speed applications and for limited times.

 

WHAT????

In a true 4x4, driving straight ahead, the front wheels should be turning at exactly the same rate as the rears. The only exception to this I know of is is in mud-drag cars. Definately NOT the case with our trucks.

All Wheel Drive systems (such as the AWD V-8 Explorers or the Subaru Outback) use some type of center differential (viscous coupling, electro-hydraulic clutches or gears) which allows the front wheels to travel farther than the rears when turning. Turning in icy or sloppy conditions is MUCH easier with AWD than with a 4wd because the system allows the front wheels to travel the extra distance when cornering.

In either case, the fronts will be traveling the same speed as the rears when traveling in a straight line.

Now, as for the noise at hand, it's possible that you have a bad u-joint or CV joint. It's not uncommon, but should definately covered under warranty (assuming it's still under warranty, anyways). The only additional noise you should notice is a slight humming from the front drivetrain components (it'll feel more like a very slight increase in the road noise.... shouldn't be sharp or loud).

Let us know what you find!

-Joe

 

well, it goes in the shop on next thursday. they service dept. guys seem to think that it could be either hubs, t case, front diff, or u joints on the front. More to follow......

 

my 97 f-150 and 96 ranger both have the same noise when locked in 4wd when the recommended mph is exceeded.... sorry but i have to tell you that in the owners manual the factory recommends that you DO NOT exceed 35mph while in 4fwd. it may be different for your vehicle but as a general rule since i was 11 years old any vehicle with the hubs locked in should not exceed 35mph in any conditions unless it is speciically designed for the driving you are doing.... ie. offroad racing awd street cars etc. etc.

 

I've seen some interesting claims on here, but this is a new one for me..... and absolutely wrong.

On the 97-current F-150s, the 4wd can be safely engaged at any speed up to 55mph. The 4wd can be used at ANY speed up to the maximum speed of the vehicle. It's probably not a good idea from a common sense standpoint, but can be done without hurting anything mechanically.

-Joe

 

i agree, both my parents and alot of people in my family have ford 4x4 pickups, and in 4x4 hi have driven on the interstate at interstate speeds several times without problems......

 

well, talked to the service manager, after test drives and finally pinpointing the noise, they are going to be replacing the passenger side hub abd wheel bearing, and more to follow........

 

well the hub and wheel bearing didn't work , so i got a new transfer case, and that worked. 18k miles and a transfer case goes?? that i find troublesome......