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| | | | Joined: Oct 2016 Posts: 8 'Bolter | | 'Bolter Joined: Oct 2016 Posts: 8 | I am the newest owner of a '67 Chev C10 Truck with inline 6 and want to change the oil. I understand that full synthetic is not necessarily a good idea due to its tendency to leak in older engines such as the 250. That being the case, what is the best oil and best weight recommended. Hybrid? Straight non-hybrid? Mobil, Castrol or ?
Thanks,
Last edited by Smitty550; 05/29/2017 3:13 AM. Reason: left out a phrase
| | | | | Joined: Feb 2000 Posts: 5,241 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,241 | Any oil you like will work. I have run Mobil 1 full synthetic to diesel oil in mine. For a total stock engine, 10 w 30, up 20 w 50 will work. 10 w 40 is probably the best all around weather oil. The synthetic did drip out the rear main more then standard oil, that and the cost made me switch. The 5w20 I run now isn't much better for leaking, but the cost is cheaper. | | | | | Joined: Apr 2015 Posts: 336 Shop Shark | | Shop Shark Joined: Apr 2015 Posts: 336 | I'd go with 10W 40 and any brand but castrol.
1959 3100 Apache Fleetside
| | | | | Joined: Feb 2004 Posts: 29,878 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,878 | The water-thin oils like 5W-20 don't cushion moving parts as well as thicker ones, so it would be hard to give me a truckload of that stuff to run in a stovebolt engine. It makes them sound like there's a bunch of little guys with sledgehammers inside, trying to get out. I run 15W-40 in everything on the farm, from lawn mowers to Diesel tractors, and all the cars and trucks. Buying it in bulk in 5 gallon buckets helps, cost-wise, as well.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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Love your enemies and drive 'em nuts!
| | | | | Joined: Oct 2016 Posts: 916 'Bolter | | 'Bolter Joined: Oct 2016 Posts: 916 | "It makes them sound like there's a bunch of little guys with sledgehammers inside, trying to get out"
Okay, that was funny...
~ Dave
1950 Chevrolet 3600 3/4-ton with 261 engine & T5 Transmission
| | | | | Joined: Dec 2008 Posts: 1,923 'Bolter | | 'Bolter Joined: Dec 2008 Posts: 1,923 | If the manufacturer's recco is known (it's on your radiator support, door jamb, owner's manual, and every Clymer's and Chilton's ever written) use it. Unless, of course, you have an advanced engineering degree.
Otherwise, select the 1st number (before the "W", which is "winter" not weight) on the basis of the coldest air temperature the engine will see before the next change. Too high: very slow cranking + oil doesn't reach the farthest bearings for 30 seconds. Too low: no oil pressure at idle.
Select the 2nd number on the basis of how hard will be engine be used + how loose are the bearings.
Ecuador: 20W, South Pole: 0W.
New engine: (W)30, race or ancient: (W)50.
How about straight 40 weight? Great for Venus, otherwise no. | | |
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