8V71 Oil Change Interval in Hours?

[Rick Brown]

I just had my 8v71 rebuilt & feel the need to service it properly, but
have no odometer, but have hour meter. Anybody know the 8v71 oil
change interval in hours of operation?
Thanks
-Rick Brown in Reno, NV

[NJT 5573]

Rick, the hours interval is flexible. If its in an earthmover its every month. My conversion is used about 6000 miles if I don't do a coast to coast trip. The years I do Florida it is used about 10,000 miles. I change it every year without oil analysis. At this point I'm ready to start using oil analysis and won't be surprised to see a 3 year interval. When I bought this bus I pulled the pan to install new main and rod bearings. The bearings looked like new so I put it back togather. I use a Lucas oil additive. It looks like I could be to old to remember to check the bearings again at 200,000 miles. The Eagle manual has no reference to hours. It does say change oil filter at 25000 miles and oil at 100,000 miles. This engine seems perfect for a luberfiner with a Harvard filter, you could probably drive it for life and just add oil! It would be good if Rotella Full Synthetic met the CF2 spec, I wonder ..... If your engine uses a gallon of oil every 1000 miles it will be due for a filter change after it uses the 25th gallon of add oil and need a complete change after it uses the 100th gallon of add oil acording to the Eagle manual! Silver Eagle says to  remove the engine at 400,000 miles. Thats 4 oil changes over the projected life of the engine but its also a lot of makeup oil!

[Barn Owl]

I have recently become a true believer in oil analyses. I found that some of my equipment was being changed to often, and my bus needed a change well before I would have though it would.

[TomC]

Thee best way to determine oil change interval is with oil analysis.  Some of the instructions that originally came with some of the buses, especially the 1980's vintage had the infamous 25,000mi oil filter change with 100,000mi oil and filter change.  I know, my 1980 KW with a 8V-92TA had that recommendation.  In about 1982, Detroit reverted back to the standard 12,000mi oil and filter change.  If you do less than 10,000mi a year, then have the oil analyzed then.  My last oil change went 2.5 years, and even then wasn't ready.  I changed my Allison for the first time 12 years after buying it, and the oil was still good! 
If you want to convert the miles into hours, usually 40-50 miles per hour is the conversion-50mph if mostly on highway, 40mph if just putting along on the back roads.  So for instance, at 50mph the 12,000mi oil change would be 240 hours.  Good Luck, TomC