Hi all, I just bought a 1994 Cat 312 and was thinking of using Shell Rotella T6 5W40 full synthetic engine oil in it. I live in Maine and will primarily be using the machine in the warm months but will occasionally also use it in the winter. I'm new to heavy diesel machinery but have read good things about Rotella and thought a full synthetic with the 5W40 temp range would be good. I also have a 2017 New Holland L228 skid steer that I use all year in all weather and was thinking of using the same Rotella in that too, to keep things simple. What do you think? Is 5W40 full synthetic a safe bet or do you recommend something else?
IMHO you are going to be changing the oil in the 312 based on time, not hours. That would remove any benefit of using a synthetic oil. Engine oil change if you do it according to the O&M Manual is every 3 months or 250 hours, whichever comes first. That 3mos time frame could be streteched somewhat, but not infinitely. Any oil meeting API CF-4 (or higher specification) would do the job. Either a 10W30 or 15W40 would be suitable for your climate conditions.
If I'm reading you correctly, you're saying that I'd be wasting money because if I'm changing my oil every 3 months as per OEM manual, dino oil is just as good as synthetic. Is that what you mean? If so that's good advice. But if I did switch to a full synthetic do you see any problems with putting synthetic in an older machine? I should say that the previous owner used a 15W40 blend for the past 5 years with no issue. Regarding viscosity, I regularly have winter temps in the single digits (fahrenheit) and sometimes into the minus teens or lower, so that's why I was leaning to a 5W rather than a 10W or 15W.
Pretty much. I'm sure you could stretch the 3-month recommendation quite a bit but not sure that even then it would make the synthetic a viable proposition in terms of $$. If the previous owner was in your neck of the woods and was using 15W/40 there is no reason why it wouldn't work for you also. Or use 10W30 if you are not comfortable with the 15W40. All you need do for a first start on a cold morning is let the engine run for a few minutes before putting any load on it. Daily greasing & inspection is a good task to occupy that time.
Just my $.02, You won't really want to run that machine if its down in single digits and below zero. It can be done, loggers run all winter, but you aren't going to like it. Every time you try to run it you are going to bust a leak somewhere, have a problem with something. The newer skid loader won't be so bad, but the old iron is tired to begin with. The best thing to do when it is -15 out is look at your machine out the window, (or better yet, look out the window at the shop the machine is sitting inside of) drink coffee and read HEF posts.