Gasoline Mileage improvement after break in.
This is the first vehicle that I have ever owned, and I have owned many, that actually improved its fuel mileage a lot after the first 5,000 miles. It is a Silverado 2500HD with the 6.0 gasoline engi...
Forum Discussion
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It might be possible to temporarily run rich fuel in heavy duty non-EPA regulated engines during break-in, but I don't know why.
Running a richer mix during break-in is reminiscent of old gas/oil mix 2-stroke engines used in dirt-bikes. I can't see how that could affect a modern 4-stroke unless straight gasoline had lubricating qualities. I would think a greater fear would exist that excess "dry" fuel would wash down cylinders thereby depriving them of adequate oil film. That was a reality with the old carburator "ball-park" systems and one of the reasons modern FI (fuel injection) engines last longer. Remember how backyard mechanics used to whine about EPA and FI? Now it's diesel owners turn.
What would break-in for better 4-stroke fuel economy on modern engines? Maybe it's a leftover tale from the past.
Consider an older flat tappet camshaft, for instance. Apparently the newer roller cams help with friction, particularily regarding the use of more aggressive lobe profiles to stretch the powerband at both ends and the middle, idle to rated hp. But that shouldn't affect newer roller cammed engines during break-in. Old engine designs, yeah.
The piston rings used to have more static tension and now have less to reduce friction. That again wouldn't affect newer engines break-in as much as older designs.
I was considering adding 10W30 motoroil to changeout an old (1978 IT) dirt bike transmission this weekend and couldn't remember what oilgrade OEM called for. My son mentioned that he had read that newer oils have added friction modifiers and standard motoroil now affects the wet clutch. A web check said 10W30 OEM, so that is what it got. Unfortunately I discovered the ancient air-cleaner foam had turned to dust, so no trial. But the point is, ordinary oil may be slipperier than in the past. Again, that would not affect breakin.
Bearing inserts haven't changed much.
So what breaks in now... as someone else asked earlier?
Wes
...
It might be possible to temporarily run rich fuel in heavy duty non-EPA regulated engines during break-in, but I don't know why.
Running a richer mix during break-in is reminiscent of old gas/oil mix 2-stroke engines used in dirt-bikes. I can't see how that could affect a modern 4-stroke unless straight gasoline had lubricating qualities. I would think a greater fear would exist that excess "dry" fuel would wash down cylinders thereby depriving them of adequate oil film. That was a reality with the old carburator "ball-park" systems and one of the reasons modern FI (fuel injection) engines last longer. Remember how backyard mechanics used to whine about EPA and FI? Now it's diesel owners turn.
What would break-in for better 4-stroke fuel economy on modern engines? Maybe it's a leftover tale from the past.
Consider an older flat tappet camshaft, for instance. Apparently the newer roller cams help with friction, particularily regarding the use of more aggressive lobe profiles to stretch the powerband at both ends and the middle, idle to rated hp. But that shouldn't affect newer roller cammed engines during break-in. Old engine designs, yeah.
The piston rings used to have more static tension and now have less to reduce friction. That again wouldn't affect newer engines break-in as much as older designs.
I was considering adding 10W30 motoroil to changeout an old (1978 IT) dirt bike transmission this weekend and couldn't remember what oilgrade OEM called for. My son mentioned that he had read that newer oils have added friction modifiers and standard motoroil now affects the wet clutch. A web check said 10W30 OEM, so that is what it got. Unfortunately I discovered the ancient air-cleaner foam had turned to dust, so no trial. But the point is, ordinary oil may be slipperier than in the past. Again, that would not affect breakin.
Bearing inserts haven't changed much.
So what breaks in now... as someone else asked earlier?
Wes
...
