RR maintenance suggests (oil & trany)

[glenncof]

I have 1991 RR with 169K and have some suggestions.

1) My 3.9l runs dirty and it has a dinky oil filter off the front of engine. I can tell this by the weight of filter (old vs. new) as I change the oil myself. (For reference I also do my Porsche 911 and a 1997 Chevy Tahoe).

At about 94K I started getting tappet noise and only 1K miles per quart.

I started oil changes every 1K with double size WIX 51459* (there is a FRAN cross reference also or PH1 will do but only 50% larger than stock). Oil GTX 20W50 in Northern California. Did this about 10 times then gradually increase changes to every 3,500 miles, adding only one quart after 1,500 miles.

* This filter cleared the front cross member but needed rubber strap wrench.

NOW it's running SWEET, almost inaudible at idle.

I can easily see the engine lasting another 100K.

2) Another high mileage suggestion; I have been draining the transmission every "other" oil change. Sooo....simple,a drain plug in the center of transmission pan. Do it at oil change so no extra mess.

I assume previous owner changed it at 30K as scheduled and I had it changed at 60K. I started this at 148K and have done 5 times so completely flushed; much smoother shifts, running quiet. I'll probably back off to every third oil change.

Total capacity is 8 quarts but only 4+ quarts come out. Balance stays in torque converter. Dextron III ... buy gallon + 1 quart. Pour in the gallon and top off ~1/3 quart after checking level (mine is cold idle in Park after shifting thru the gears).

I wish I had known how easy this was and started sooner. These transmission are expensive and the gallon of Dextron III is only $6 at Kragen.

I do not replace transmission filter since it requires removing tail pipe from exhaust manifold <can you believe it> and a bolted cross member. The repeated changes not only refreshes fluid (50% each time) it gradually transports out the very fine partical sluge that resides in the bottom of the pan. (I changed my 1997 Chevy Tahoe at 105K and wiped it out with a rag. Unfortunately the chevy has no drain plug so changing is Very Mess Job.)

Don't completely FLUSH (this cleans and replaces 100% fluid) as I have heard of some problems with slippage afterwards. The above is nice gradual cleaning. You'll see the fluid get more clear each time until about 5th change.