Transmission whine in reverse 2008 fx4

[kburley]

hey guys. i bought a 2008 fx4 yesterday. this afternoon i noticed a strange whining noise in reverse that i hadnt heard previously.

when in reverse, there is a very high pitched whine that changes in tone and intensity in line with engine RPMS

when i shift to drive from reverse, the same whine continues at high intensity for a fraction of a second then disappears. everything else about the trans seems to be operating fine.

there are no other conditions under which i can re-create the noise, which rules out vaccum leaks for me.

can anyone provide insight on what may cause this? the truck came with a 30 day powertrain warranty so if its anything remotely major ill likely bring it back to the dealer to look at. thanks in advance

 

[kburley]

UPDATE: checked the fluid. not only is the level ok, but the fluid is clearly brand new. its a light pink colour, almost clear. could this noise be the result of some crap getting disloged when the fluid change was taking place? at this point, im not even sure if i should be concerned about it. thanks

 

[adsm08]

A lot of transmissions whine in reverse, but usually only while moving.

Reverse runs a higher line pressure, so there may be something leaking internal to the transmission and causing a reed-type noise.

 

[kburley]

A lot of transmissions whine in reverse, but usually only while moving.

Reverse runs a higher line pressure, so there may be something leaking internal to the transmission and causing a reed-type noise.

mine does it when not moving as well. i understand what you mean about the reed noise. but is this internal leaking a big deal? should i be worried about it? or is it relatively normal/common?

 

[adsm08]

Certainly not normal, not sure about common.

I know that trans has issues with valve body gaskets. Not sure if that is where your issue would be or not, I'm not really a transmission guy.

 

[kburley]

Certainly not normal, not sure about common.

I know that trans has issues with valve body gaskets. Not sure if that is where your issue would be or not, I'm not really a transmission guy.

hm. i suppose im looking at a warranty claim then! just my luck. thanks