Anyone with 5.13? On a automatic?
06-06-2011, 01:30 PM
#21
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An excerpt from randys r&p:
The link:
hxxp://www.ringpinion.com/ContentFrame.aspx?FilePath=Content/Parts/RingAndPinions//New_Gear_Break-In.inc
A lot of people say 'screw the break-in' and have no issues. I prefer to err on the side of caution, though. I mean, really, I went to a higher gear ratio because I got bigger tires, and it's not too difficult or demanding to drive easy for a couple of days, and pull over a few times and find something to do until they cool. But like everything else, it's a judgement call.
In most stock vehicles with stock tires there is seldom a risk of a burned gear set. For those of us who modify and use our trucks, there many situations that can contribute to burned gear syndrome. Motorhomes, towing, tall tires, and high numeric gear ratios (4.56 & up) can all generate a lot of heat and cause the gear oil to break down. The greatest damage to a new gear set results from running for ten minutes or more during the first 500 miles when the oil is very hot. Any heavy use or overloading while the oil is extremely hot will cause it to break down and allow irreversible damage to the ring & pinion.
In order to make them run cooler and quieter, new gears are lapped at the factory. However, they are not lapped under the same pressures that driving creates. The loads generated while driving force any microscopic high spots on the gear teeth back into the surface of the metal. This is called "work hardening". Work hardening is similar to forging in the way that it compresses the metal molecules into a very compact and hard formation. This can only be accomplished if the metal surfaces are lubricated and the gear temperature stays cool enough that the molecular structure does not change. If the temperature of the metal gets hot enough to change the molecular structure, it will soften the surface instead of hardening it.
In order to make them run cooler and quieter, new gears are lapped at the factory. However, they are not lapped under the same pressures that driving creates. The loads generated while driving force any microscopic high spots on the gear teeth back into the surface of the metal. This is called "work hardening". Work hardening is similar to forging in the way that it compresses the metal molecules into a very compact and hard formation. This can only be accomplished if the metal surfaces are lubricated and the gear temperature stays cool enough that the molecular structure does not change. If the temperature of the metal gets hot enough to change the molecular structure, it will soften the surface instead of hardening it.
hxxp://www.ringpinion.com/ContentFrame.aspx?FilePath=Content/Parts/RingAndPinions//New_Gear_Break-In.inc
A lot of people say 'screw the break-in' and have no issues. I prefer to err on the side of caution, though. I mean, really, I went to a higher gear ratio because I got bigger tires, and it's not too difficult or demanding to drive easy for a couple of days, and pull over a few times and find something to do until they cool. But like everything else, it's a judgement call.
Last edited by nthinuf; 06-06-2011 at 01:33 PM.
