We have a BEI Grape Harvester at our winery. Our vineyard manager uses SAE 30W oil in it, along with ALL the other tractors we have. He uses the harvester in the fall when the temps are a bit on the coolish side and sometimes he has to put heat lamps on the oil pan to get the engine started. What do you think? Wouldn't better grade oil and perhaps synthetic oil help him out, along with the Ford TN95, the Ford 1900 and Ford 3000 tractors? I can see 30W only if he were farming in Colorado or Nebraska in the summer, but here in SW Michigan, it really doesn't get that hot out. Would the 10W-30 or the 10W-40, etc oils you can get for automobile specs do well for these agriculture applications?