Hello,

I have a 2003 Discovery II with 121,000 miles. Generally the truck is in great condition and the engine has run strong with no problems so far (purchased at 104,000) with the exception of the occasional "Oil Service" light.

The other week my wife got the "Service Engine" light flashing with some initial roughness in the idle which smoothed out after about a minute and the light went solid. She brought the car home to me and shut it down. When I checked it out the car ran fine with no dash lights but I heard a sporadic clunking/tapping sound coming from the oil pan/transmission area but only when I released the gas pedal. I suspected that it was the oil pump gear so this weekend I changed the oil pump gears (outer-ring cracked in 5 spots), water pump, timing chain etc.

However, after start up the truck runs great but I still hear the sporadic clunking from under the car. Again, it only happens when I release the gas pedal and it seems to completely disappear once I drive for a few minutes And the transmission warms up which lends me to think that it may be a transmission issue. Any input would be greatly appreciated.

 

Have you ever rebuilt or replace your fron drive shaft, how often do you grease all the 6 grease fittings?

 

Hi...thanks for the quick response! No, I have never greased any fittings or rebuilt any shafts but am willing to try anything to resolve this problem....

 

I was having this same problem, along with a bird chirping noise. Got under it to check the front shaft and sure enough the shop hadn't been greasing the u-joints. Pulled out the shaft, swapped out the joints. No more clunk, no more chirp. Hope your fix is as easy as mine was.

 

Did you also replace the centering ball, if not it will fail again real soon.
Also make sure to grease the u-joints every oil change.

 

After getting under the car and checking everything out it ended up being the catalytic converter. Something inside was banging really loud evertime I would release the gas and it sounded like someone was banging on the bellhousing with a screwdriver handle. So I cut it off and installed a new converter and the truck is running great with no more banging sound.

 

So if the truck was in park, revved up, then let off gas, it would bang even though stationary?

 

Yes. Replaced the centering ball as well.

 

If you need a drive shaft let me know. Its $300 shipped