roaring noise

[Kingfish999]

My 04 4X4 Expo has always had a roaring noise when driving for as long as i can remember it. I always assumed it was the tires because it had some cheaper ATs and sounded exactly like road noise with mud terrains. seems to come from everywhere, not just one particular corner.

But through a weird circumstance, i ended up getting a set of 2015 wheels with brand new ATs on them for a few months, and then got another set of 2015 wheels with some older street tires on them which i currently have. the noise between all 3 sets never changed the sound. the 2015 both sets came from never had any road noise

the 4x4 vacuum actuators seem to be working fine. truck has 80k miles and was babied and everything else seems ok. is there anything specific to these trucks i should check? does this generation just tend to have more road noise?

 

[99WhiteC5Coupe]

My 04 4X4 Expo has always had a roaring noise when driving for as long as i can remember it. I always assumed it was the tires because it had some cheaper ATs and sounded exactly like road noise with mud terrains. seems to come from everywhere, not just one particular corner.

But through a weird circumstance, i ended up getting a set of 2015 wheels with brand new ATs on them for a few months, and then got another set of 2015 wheels with some older street tires on them which i currently have. the noise between all 3 sets never changed the sound. the 2015 both sets came from never had any road noise

the 4x4 vacuum actuators seem to be working fine. truck has 80k miles and was babied and everything else seems ok. is there anything specific to these trucks i should check? does this generation just tend to have more road noise?

Does the engine have electric radiator cooling fans, or does it have a belt driven cooling fan with a coupling that engages with speed?

The mechanical fan coupling can fail and cause a roaring noise.

 

[Kingfish999]

no its not the fan clutch. it seems like something drivetrain related. , its definantly speed related

 

[kep5niner]

Could bearing(s), front dif, rear dif, transfer case, u-joints. Does the sound fluctuate with wheel RPM, engine RPM? Any associated vibration in conjunction with the sound? Have you checked ALL fluid levels?

 

[Fastcar]

Drive it up to speed and put it in neutral and see what happens. If no change leave it in neutral and shut the engine off and see what happens with the noise. Remember that there will be no power brake or steering when shut down!!

 

[Kingfish999]

like i said its exactly the same noise as you would expect running aggressive mud tires. i thought it was the tires for years untill i tried 2 other sets of tires. its completely related to speed and first becomes easilly audible from 20mph
and increases from there. doesnt matter what load or gear its in, accelerating or decelerating. only what speed its goes

for all i know it might just be its natural noise of the truck. all my other trucks are highly modified poopboxes with performance engines, loud exhaust, and alot of wind noise and loud music. this is the only stock vehicle i ever really had. and its been like this for as long as i can remember

im very mechanical, i build all my trucks. i jsut wasnt sure if there was a specific reason for a noise like this attributed to expeditions.

its not particularly one side or corner. seems like all 4 do it

 

[kep5niner]

I had a similar noise (as best as I can tell from your description). I couldn’t tell where it originated, but most noticeable between 20-50 MPH. I ruled out tire noise, bearings, trans. Turns out the front end shit the bed. Dealer replaced under extended warranty. This was at about 65k miles. I’ve put another 10k on it since with no issues.

 

[Kingfish999]

what failed? the front differential?
not sure what they use on that year to engage the front. on this generation it uses vacuum actuators at each wheel so as long as they operate properly and t-case is in 2wd, it should never use the front diff. so front shafts and diff dont spin

kinda odd how they operate. they default engaged when no vacuum is present and unlock when vacuum applied. so every time the truck starts they unlock themselfs and reengage when shut off. guess it makes 4x4 more reliable and keep them moving so they dont stick from non-use