Would 15W40 be too heavy for my H??

At the farm where I occasionally pitch in, the local oil jobber has installed a 200 gallon bulk tank in shop and keeps it filled with 15W40. For many years the oil has been used in EVERYTHING on the farm with an engine: 855 Cummins turbodiesels in the big tractors; older 4020 gas & diesels; antique Deere, IHC and MM tractors; the owner's wife's Buick; even her lawnmower. About the motors that don't get 15W40 are the 2 stroke motors in the chainsaws and snowmobiles.

I approached my oil supplier and wanted to see the specs on every oil he sold. I took this info home with me and studied it. He was not even selling me the oil recomended for 3 diesels I owned. When I confronted him with this he advised Esso series 3 oil was only for severe service in diesels. I asked what he considered severe service. His reply," dozers, forestry skidders, etc. " I said,"That is interesting, a dozer spends half it's life backing up under no load, skidder spends half its life going back into the bush empty, yet my farm tractors are loaded 95% of the time." I took home a supply of his best diesel engine oil, single viscosity at that time and used 30 in summer and 20 in winter. About 10 years later I switched to 15 - 40 in the same oil and never looked back. I have never had a car or pickup engine that didn't give 250.000 miles of service. As of 2004 that includes 4 cars, 4 pickups, 2 larger trucks and the lawn mower. I believe I am well above the average on hours of service with pickups and cars. I can take you to a dozen other people with the same results. I probably have on my farm logged a 100,000 hours on tractor, combine, skid loaders and other engines with exceptional results.

I think over the years the 6.2 diesel was probably the most amazing engine I had. To start with that engine didn't have a great reputation for longeviety. My friends all laughed at me when I bought it in the winter of 86-87. It was an 85 model a guy traded for a Ford diesel because they had more power. What I noticed on the spec sheet on this truck, it's ratios were such that it would turn 1800 rpm at 60 mph. Every year my friends kept kidding me on when this old 6.2 was going to blow up. They annoyed me so badly on this I decided I am deiving this truck until the engine blows up, if I live long enough. That one used to get their goat. Well in 2002, the old truck with close to 500,000 miles was getting quite bad on the rust factor. During servicing one day I noticed my frame was broken behind the cab about half way to the rear spring hanger. That ended the old truck, it was held together well as I had put a steel flat deck on it. I never took it on the road again, used it around property some. Finally a guy bought it for the engine to put in an old 4x4 to plow snow with. I questioned the wisdom of putting that old engine in another truck. The buyers responce, 6.2's will run forever if you keep them under 2500 rpm. He said," if you see a Chevy diesel with 4.10 gears run the other way, it's had too many hours at 3000 rpm." He said he knew that was not the case with my truck as it had always seemed like it was idleing as I drove throughout the community.