Help with my 04 explorer--TC?

[cztexas]

Whenever I gave a little bit sudden acceleration on gas pedal, I can hear some noise from powertrain. Like "pa pa". like loose chain or grind noise from the front? If I give a gentle gas, everything is ok. engine should be fine, since in "N", no noise.

I am thinking the transfer case. I did try 4x4 high and 4x4 low. Everything looks fine. Only the noise.

Any idea? Thank you~~~~

 

[94Eddie]

If the noise disappears when the torque convertor locks into overdrive then it is the convertor. My 2002 has the rattling torque convertor and as soon as overdrive engages the noise stops. Until then it sounds like a can of pennies being rattled, chattering etc.

 

[madkhalywad]

if the sound from engine front most likely is the cam shaft chain cassette is broken

 

[stoogefan]

Sometimes the auto-4x4 can kick in, if it senses unequal rotation between front and rear, causing strange noises. Check your tire inflation and make sure that the front and rear tires are wearing evenly (the same diameter).

 

[cztexas]

if the sound from engine front most likely is the cam shaft chain cassette is broken

Thank you for your info. But this can be elimiated by put gear in "N" and speed up engine but no noise.

 

[cztexas]

Sometimes the auto-4x4 can kick in, if it senses unequal rotation between front and rear, causing strange noises. Check your tire inflation and make sure that the front and rear tires are wearing evenly (the same diameter).

Will some lights (like 4x4 high) will on if 4x4 kicked in? Thank you.

 

[cztexas]

If the noise disappears when the torque convertor locks into overdrive then it is the convertor. My 2002 has the rattling torque convertor and as soon as overdrive engages the noise stops. Until then it sounds like a can of pennies being rattled, chattering etc.

Hi, what's mean for "overdrive engaged"?
I only test it at low speed (<40). It only occurs when sudden pushing gas pedal (like tapping).
Thank you.

 

[94Eddie]

Hi, what's mean for "overdrive engaged"?
I only test it at low speed (<40). It only occurs when sudden pushing gas pedal (like tapping).
Thank you.

You need to be going 45-50 mph for the torque convertor to lockup. You can watch the tach and see the RPMs drop when it happens. It helps to hear the noise, or lack of noise, by driving next to a guardrail with the window down. The sound bounces off the guardrail and into the cabin.

Mine will make little noise when the engine load is light. Other than that is rattles quite loudly. Once the torque convertor locks it completely disappears.