Okay, so I've owned the '02 RR for two weeks now. When purchased, there was what I was certain was an exhaust leak on the passenger side. You couldn't hear it from up top or from the left side, just when bending down on the right side. Rolling down the street or the highway, you really couldn't hear it. Engine ran smooth and strong with the only questionable issue being a rough idle...oh, and the cruise would hunt and wander.

Fixed the cruz by replacing vacuum lines, then added some B12 Chemtool to the fuel, then cleaned the MAF and Throttle body, that was really filthy. Ran better, but still not a smooth idle. Put in enough hwy miles to run one complete tank with cleaner through it.

Plan for today was to wrap up a couple of other interior issues. However last evening while taking the wife out for dinner the "sound" became more prevalent. Based upon the sound, I was still thinking an exhaust issue or possibly a plug.

Today I first checked for a loose plug...no luck. Then running I began checking for an exhaust leak. Pulled it up on ramps and went below. Moving side to side, i pinned the location of what seemed like a high-frequency knock in the area located where the bell housing mates to the oil pan.

Reading several forum posts, I pulled the oil pan to be able to see what I could find. Unfortunately, I couldn't locate anything that was obvious to me. No wear marks, nothing broke or loose...at least not that I could see. I rotated the crank several times while I was checking the bolts on the flex plate to torque converter. The only thing we noticed was that the two middle sets of rod connectors seemed to be less oily then the front and rear.

One thing I noticed when draining the oil, after having only ran the engine for a few minutes was how thin or watery it seemed to be. The hope was at this point, was that a new filter and good quality 15w40 oil might be the answer...yeah, I know.

One thing I noticed was that the Valvoline filter that was in place, was definitely smaller than the Bosch filter I had just purchased. The seal ring matched, but the filter itself definitely was considerably smaller. So, I went online and double-checked my purchase...correct Bosch filter. So I'm guessing the PO had taken the vehicle to Valvoline quick boys...so if the filter was in question, what about the oil that was installed?

New filter and oil in place, cranked the engine shut a 2nd twice to make sure oil pressure was there. Then fired it up. Right away the engine seemed smooth and quieter. Then as it warmed up, the previous noise in question slowly started coming back. Checked for leaks, then had the wife drive slowly up and down the cul-de-sac a couple of times. By the time she returned, it the noise was definitely there...barely detectable from the top passenger side of the engine, a bit more detectable from the driver side top, but definitely detectable from a stooped position by the passenger mirror.

Back down below with a tube for listening to determine exact location...I tried all over. The high pitched knock was most prevalent when I placed the tube on the "flaps" of the oil pan, where the top of the pan flairs out and becomes wider before making contact with the bell housing.

So, now we have the location of the knock/noise and it appears to become more prevalent as the engine warms. Thoughts Please?

Is it the rear main? Rod bearings? I read the RAVE instructions for the rod bearing replacement; doesn't seem to terribly difficult. Is the rear main also replaceable without pulling the entire crank?

Am I going in the right direction? Other things I need to consider?

Thanx in advance for anyone's assistance who has experience with the lower ends.

 

Have to move tranny/transfer case to get at the rear main seal. Don't pull crank. Shows in Rave under Engine, two technical parts, seal and torque converter drive plate.

One concern might be that oil pump could be making this noise and it is telegraphed through some internal part of the engine. You may want to do a manual oil pressure test, both cold and warm, at idle and 2500.

As to PO and oil changes, he may have gone with the once a year plan. Many of our members prefer every 5,000. 15W40 diesel oil, like Shell Rotella, is a good choice. But no matter which posh pure petroleum product from Prudhoe Bay is used, do it early and often. And use a good quality filter, Bosch, Wix, Mobile1, etc. Some swear by Fram, others swear at it. I happen to run a WIX jumbo filter that adds almost another quart of capacity (but it has larger micorn rating, so is not as "clean" as Mobile1).

BTW - good job on the post - lots of good info.

 

Thanx for your thoughts Savannah. Lots of research, reading and anguish yesterday. Today, decided to take it on our 3-block trip to the grocery store. When parking, still noticeable. Trip back to house...yep, still there.

Then we decided to run a few more errands...about 3-4 miles away at 25-35mph. We had dropped the windows and noticed we couldn't hear the noise bounce back off the fences along the road about 1.5-2 miles into the trip. We thought perhaps we just couldn't hear it for the road noise. Arrived at store...not a sound one!?! Ran smooth down the road usual, but this time, not a knock, clatter one. After a bit of shopping, off we went to our next stop and this time reaching highway speeds for about a mile. Arrived at store...still running smooth and the mystery noise was still gone. As it was on the 7 or so mile meandering somewhat scenic route back to your house. Arrived in driveway and still no noise.

Yes...my prayers to the Range Rover gods were answered and for that I am grateful. However, I am a cause-n-effect guy...SO, I'm still questioning the source. I had kind of somewhat hoped that a journal had been restricted or clogged and that the filter and oil change might be the answer. Perhaps unrealistic, but I had hoped. So as it stands, running smooth and great down the road...still a little rough on idle...and now just no knocking/clattering noise???

 

If you had just changed your oil recently, it may have dissolved some sludge and changed the noise. You still may wish to do an oil PSI test, or install an oil pressure guage (Glowshift is one brand, attaches to adapter added to oil filter).