Abstract:
A baffle for use in a lubricant pan of an engine that uses a lubricant having a viscosity. The baffle includes a first sheet and a second sheet substantially aligned with the first sheet, the sheets are sized and shaped to reduce turbulence of the lubricant in the lubricant pan. The baffle also includes a tube having a first end and a second end, whereby at least part of the tube is sandwiched between the first and second sheets. A first tube connector is connected to the first end of the tube. A second tube connector is connected to the second end of the tube. A plurality of draining apertures are formed in the first and second sheets, whereby the size of the draining apertures are based on the viscosity of the lubricant.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    This invention relates generally to engine components, and more particularly to baffles in a lubricant pan of an engine.  
           [0002]    It is well known that internal combustion engines are generally lubricated with oil to maintain the engine components in good working condition. In most instances, an oil pan is utilized to hold oil that is circulated throughout the engine. An oil pump pumps oil from the oil pan toward the top end of the engine, where the oil is routed via internal passageways to the various engine components. The oil drains back to the oil pan under the influence of gravity, where it accumulates and is circulated back to the top end of the engine by the oil pump.  
           [0003]    During acceleration, braking, or maneuvering of a vehicle utilizing a typical internal combustion engine, the accumulated oil in the oil pan often sloshes and/or splashes against the oil pan walls. Conventional engine oil pumps utilize a pickup submerged in the accumulated oil to feed the oil pump. The sloshing and/or splashing oil in the oil pan (sometimes referred to as “turbulence”), in extreme conditions, can uncover the pickup, therefore causing a low oil pressure condition in the engine. The movement of the oil can also cause it to foam.  
           [0004]    To prevent such sloshing, splashing, or foaming, a baffle is usually positioned in the oil pan. The baffle restricts the movement of the accumulated oil in the oil pan. Such baffles typically include sheet metal bodies that are welded or fastened in place in the oil pan.  
           [0005]    It is generally known in the art that excess heat can degrade the performance of lubricants. Overheating can result in thermal breakdown of oil such that the oil looses its ability to maintain a lubricating layer between moving components. Removing built-up heat in the oil, which can be accomplished by using an oil cooler, helps maintain the oil&#39;s viscosity, thus preventing thermal breakdown. In conventional applications, a separate oil cooler is remotely mounted from the engine. In a typical design, a separate radiator is mounted in the vehicle to air-cool the oil. An adapter is required (typically positioned between the engine block and oil filter) to route heated oil from the engine through the radiator and back into the engine again after the oil has been cooled. Hoses are also required to route the oil both to and from the radiator. The adapter and hoses increase the number of places where oil might leak. Furthermore, conventional oil coolers add complexity to vehicles.  
         SUMMARY OF THE INVENTION  
         [0006]    The invention provides, in one aspect, a baffle for use in a lubricant pan of an engine that uses a lubricant having a viscosity. The baffle includes a first sheet, a second sheet substantially aligned with the first sheet, the first and second sheets sized and shaped so as to reduce turbulence of the lubricant in the lubricant pan, and a tube including a first end and a second end, at least part of the tube being sandwiched between the first and second sheets. The baffle also includes a first tube connector connected to the first end of the tube, and a second tube connector connected to the second end of the tube. Also, the baffle includes an aperture formed in the first and second sheets, the aperture sized and shaped for accepting a lubricant pickup, and a plurality of draining apertures formed in the first and second sheets, the size of the draining apertures being based on the viscosity of the lubricant.  
           [0007]    The invention provides, in another aspect, a baffle for use in a lubricant pan of an engine that uses a lubricant having a viscosity. The baffle includes a first sheet having a size and shape, a second sheet substantially the same size and shape as the first sheet, the first and second sheets configured to reduce turbulence of the lubricant in the lubricant pan, and a tube including a first end and a second end, at least part of the tube sandwiched between the first and second sheets. The baffle also includes an aperture formed in the first and second sheets, the aperture sized and shaped for accepting a lubricant pickup, and a plurality of draining apertures formed in the first and second sheets, the size of the draining apertures based on the viscosity of the lubricant.  
           [0008]    The invention provides, in yet another aspect, a combination of a baffle and a lubricant pan for an engine that uses a lubricant having a viscosity. The combination includes a baffle, which includes a first sheet, a second sheet substantially aligned with the first sheet, the first and second sheets sized and shaped so as to reduce turbulence of the lubricant in the lubricant pan, and a tube including a first end and a second end, at least part of the tube being sandwiched between the first and second sheets. The baffle also includes a first tube connector connected to the first end of the tube, and a second tube connector connected to the second end of the tube. The baffle also includes an aperture formed in the first and second sheets, the aperture sized and shaped for accepting a lubricant pickup, and a plurality of draining apertures formed in the first and second sheets, the size of the draining apertures being based on the viscosity of the lubricant. The combination also includes a lubricant pan housing the baffle therein, the first tube connector coupling the first end of the tube to the lubricant pan and the second tube connector coupling the second end of the tube to the lubricant pan.  
           [0009]    The invention provides, in another aspect, a method of making a baffle for use in a lubricant pan. The method includes providing a tube including a first end and a second end, bending the tube into a serpentine pattern, positioning the tube between a first metal sheet and a second metal sheet, and stamping the first and second metal sheets to at least partially sandwich the tube therebetween.  
           [0010]    The invention provides, in yet another aspect, a method of cooling and controlling turbulence of a lubricant in a lubricant pan of an engine. The method includes providing a baffle including a tube sandwiched by interconnected metal sheets, positioning the baffle over the lubricant in the lubricant pan, such that at least some of the lubricant drains onto the baffle before draining into the lubricant pan, coupling the baffle to the lubricant pan, and passing coolant through the tube to cool the lubricant in contact with the baffle.  
           [0011]    Further aspects of the present invention, together with the organization and manner of operation thereof, will become apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    In the drawings:  
         [0013]    [0013]FIG. 1 is a perspective view of one embodiment of a baffle exploded away from an oil pan.  
         [0014]    [0014]FIG. 2 a  is an enlarged partial perspective view of a portion of the baffle of FIG. 1.  
         [0015]    [0015]FIG. 2 b  is a section view along line  2   b — 2   b  of the baffle of FIG. 2 a.    
         [0016]    [0016]FIG. 3 is a partial section view of the baffle of FIG. 1 positioned in the oil pan.  
         [0017]    [0017]FIG. 4 is a section view of the oil pan along line  4 — 4  of FIG. 3, showing a connecting configuration between the baffle and the oil pan.  
         [0018]    [0018]FIG. 5 is a partial section view of a side of the oil pan, illustrating another embodiment of a baffle.  
         [0019]    [0019]FIG. 6 is a partial section view along line  6 — 6  of the oil pan and baffle of FIG. 5.  
         [0020]    [0020]FIG. 7 is a partial section view of the baffle of FIG. 1 positioned in the oil pan, illustrating an additional tube positioned in the oil pan.  
         [0021]    [0021]FIG. 8 is a perspective view of yet another embodiment of a baffle in the oil pan.  
         [0022]    [0022]FIG. 9 is a section view along line  9 — 9  of the baffle of FIG. 8.  
         [0023]    [0023]FIG. 10 is a perspective view of an oil pan including a coolant channel formed in a bottom wall of the oil pan, in combination with a baffle.  
         [0024]    [0024]FIG. 11 is a section view along line  11 — 11  of the oil pan and baffle of FIG. 10. 
     
    
     DETAILED DESCRIPTION  
       [0025]    Before embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of the examples set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or carried out in a variety of applications and in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms “mounted,” “connected,” and “coupled” are used broadly and encompass both direct and indirect mounting, connecting, and coupling. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.  
         [0026]    With reference to FIG. 1, an integral baffle  10  and lubricant cooler (“baffle”) is shown removed from an engine oil pan  14 . The oil pan  14  is used in combination with an internal combustion engine (not shown) to collect oil used to lubricate frictionally-contacting components in the engine. In the embodiment shown in FIG. 1, a rear portion  18  of the oil pan  14  includes a sump  22 , which defines the deepest portion of the oil pan  14  relative to an upper flange surface (not shown), which mates to the bottom portion of an engine block (also, not shown). The sump  22  contains a majority of the oil collected in the oil pan  14 . The oil pan  14  also includes a forward portion  26  which is shallower than the rear portion  18 . Also, the oil pan  14  includes a curved portion  30  connecting or in between the forward and rear portions  26 ,  18 , such that oil collected by the forward portion  26  of the oil pan  14  is allowed to drain into the sump  22 . Optionally, the baffle  10  may be generally linearly shaped and configured generally parallel to a horizontal plane (not shown) passing through the oil pan  14 .  
         [0027]    The terminology “forward portion” and “rear portion” is not limiting. The oil pan  14  may be transversely mounted relative to a vehicle, such as a front-wheel drive vehicle utilizing a transversely-mounted engine. Also, as a further alternative, the orientation of the oil pan  14  may be reversed, such that the rear portion  18  including the sump  22  is positioned forward-most in a vehicle, and the forward portion  26  is positioned rear-most in the vehicle. Further, in addition to the sump  22  in the rear portion  18 , the forward portion  26  may also include a sump (not shown) to collect oil therein.  
         [0028]    In the embodiment shown in FIG. 1, the baffle  10  is shaped such that it generally follows the curve of the oil pan  14  (more clearly seen in FIG. 3). Relative to its positioning in the oil pan  14 , the baffle  10  includes an upper planar section  34  and a lower planar section  38 . A curved section  42  connects or bridges the upper and lower planar sections  34 ,  38 , and generally conforms with the curved portion  30  of the oil pan  14 . Alternatively, the baffle  10  may be configured in any number of reasonable shapes, such that it does not interfere with existing components of the engine (e.g., the oil pump, crankshaft, bearing caps, etc.) or various oil pan walls comprising the oil pan  10 . Some additional embodiments are discussed below, with like components labeled with like reference numerals.  
         [0029]    As shown in FIGS. 1-2, the baffle  10  includes a tube  46  sandwiched between metal sheets  50 ,  54 . The tube  46  includes a tube inlet  58  and a tube outlet  62 , such that coolant is diverted from the engine cooling system (not shown), for example, routed through the tube  46 , and re-diverted back to the engine cooling system. The tube inlet  58  and tube outlet  62  may be reversed, such that coolant enters the baffle  10  via the tube outlet  62 , and coolant leaves the baffle  10  via the tube inlet  58 . Alternatively, a separate, independent cooling system (e.g., an oil cooling system with a radiator, or a transmission fluid cooler, both not shown) may be utilized to provide coolant to the baffle  10 . As a result, the metal sheets  50 ,  54  sandwiching the tube  46  act as cooling fins and promote heat transfer from the tube  46  and coolant.  
         [0030]    The tube  46  is configured throughout the baffle  10  in a serpentine pattern, such that the tube inlet  58  and tube outlet  62  are exposed and on the same side of the sheets  50 ,  54 . The exemplary serpentine pattern illustrated in FIG. 1 does not imply that the tube  46  is limited to any particular shape or pattern. The tube  46  may be configured throughout the baffle  10  in any reasonable shape or pattern, provided the tube inlet  58  and tube outlet  62  are exposed. Also, the tube inlet  58  and tube outlet  62  may be positioned on adjacent sides of the sheets  50 ,  54  or on opposite sides of the sheets  50 ,  54 , rather than the same side of the sheets  50 ,  54 .  
         [0031]    Both the tube inlet  58  and tube outlet  62  include flared ends  66  which capture tube connectors  70  on the respective tube inlet  58  and tube outlet  62 . The tube connectors  70  couple the baffle  10  to the oil pan  14  to support the baffle  10  therein, in addition to fluidly connecting the tube  46  with the cooling system used. As shown in FIG. 4, the oil pan  14  includes threaded apertures  74  through a side wall  78  to receive the tube connectors  70  of the tube inlet  58  and tube outlet  62 , respectively, on the interior portion of the side wall  78 . Similar tube connectors  70  couple to the exterior portion of the side wall  78  and fluidly connect additional tubing or hose (not shown) with the tube  46  in the baffle  10 . The additional tubing or hose is further routed to the cooling system employed to transport coolant both to and from the baffle  10 .  
         [0032]    With reference to FIG. 3, the baffle  10  is shown positioned in the oil pan  14  above the oil collected in the sump  22 . Bosses  82  formed in the oil pan  14  space the baffle  10  from the bottom of the oil pan  14  and provide support locations for the baffle  10 . Ordinary fasteners  86  (e.g., screws, bolts, etc.) are passed through the metal sheets  50 ,  54  and threadably engage the bosses  82  to further secure the baffle  10  to the oil pan  14 . In comparison to the metal sheets  50 ,  54 , the tube  46  is substantially more rigid. Therefore, the tube&#39;s rigidity allows the baffle  10  to be almost entirely supported by the tube  46 .  
         [0033]    During normal operation of the engine, most of the heated oil draining from the engine drops onto the baffle  10  before being collected in the sump  22 . The coolant passing through the baffle  10  continually cools the baffle  10 , which in turn allows the baffle  10  to cool any oil with which it is in contact. Apertures  90  through the metal sheets  50 ,  54  allow the cooled oil to drop from the baffle  10  into the oil pan  14 . Although the exemplary apertures  90  are circular, the apertures  90  may be formed in any reasonable shape, including triangular, oval, square, and trapezoidal. Generally, the size of the apertures is dependent on the viscosity of the lubricant being used. Lower viscosity lubricants can drain more easily through smaller openings than higher viscosity lubricants. Louvers  94  in the metal sheets  50 ,  54  may also be used in combination with the apertures  90 , or used exclusively in the metal sheets  50 ,  54 . The engine&#39;s oil pump (not shown) then circulates the cooled oil in the sump  22  throughout the engine, after which the oil drains back toward the baffle  10 , and the process repeats.  
         [0034]    The baffle  10  also helps restrict movement of the oil collected within the oil pan  14 , such that sloshing and/or splashing of the oil in the oil pan  14  is restricted. This sloshing and/or splashing movement of the oil is sometimes referred to as “turbulence.” Excess turbulence in the oil in the oil pan  14  may cause the oil to foam, thus decreasing the amount of oil available to the oil pump pickup and oil pump for circulation throughout the engine. The baffle  10  is positioned in the oil pan  14  to decrease turbulence in the oil and to limit movement of the oil, such that the oil pump pickup remains generally submerged in the oil. Also, the baffle  10  is positioned to intercept aerated, or foamed oil from the engine before it returns to the oil pan  14 . Further, the baffle  10  allows time for the foamed oil to naturally purge itself of entrained air before falling through the apertures  90  or louvers  94  into the oil pan  14 . Consequently, a conventional baffle (not shown) in the oil pan  14 , separate from the baffle  10 , is not required.  
         [0035]    In another embodiment of the baffle  10 , as shown in FIGS. 5-6, the baffle  10  includes sheet portions  98  configured substantially perpendicularly to opposite sides of at least one of the metal sheets  50 ,  54 . The sheet portions  98  each include a serpentine groove  102  formed therein, such that on each sheet portion  98 , an inlet  106  is defined near the lower planar section  38 , and an outlet  110  is defined on the opposite side of the sheet portion  98 . Also, each sheet portion  98  is positioned against the side wall  78  of the oil pan  14 , such that the combination of the groove  102  and side wall  78  forms a passageway  118  between the inlet  106  and the outlet  110 . The serpentine groove  102  is configured to route oil from the lower planar section  38  of the baffle  10  through the passageway  118 , before reaching the sump  22 . Gravity drives oil through passageway  118  between the inlet  106  and outlet  110 . By routing oil through the passageway  118 , the oil is further cooled by contacting the side wall  78 , which is air-cooled by the air surrounding the outside of the oil pan  14 . Further, the oil pan  14  may include cooling fins  122  projecting from the side wall  78  to further promote cooling of the side wall  78 . Alternatively, the sheet portions  98  may extend farther toward the forward portion  26  of the oil pan  14 , such that the sheet portions  98  are defined along substantially the entire length of the baffle  10 . Also, the sheet portions  98  may be coupled to the respective side walls  78  of the oil pan  14  rather than being coupled to the sheets  50 ,  54 .  
         [0036]    With reference to FIG. 7, the baffle  10  of FIGS. 1-4 is shown in combination with an additional tube  126  carrying coolant routed through the oil sump  22  to cool the oil collected in the sump  22 . Like the tube  46  in the baffle  10 , the additional tube  126  is configured in a serpentine pattern and includes a tube inlet  130  and a tube outlet  134 , such that the additional tube  126  is fluidly connected with the engine&#39;s (or a separate, independent) cooling system. Also, the additional tube  126  includes tube connectors (not shown) that threadably engage threaded apertures (also, not shown) in a side wall of the oil pan  14 . Like the tube  46  in the baffle  10 , the additional tube  126  may be configured in any reasonable shape or pattern. Also, the tube inlet  130  and tube outlet  134  may be positioned on adjacent sides of the oil pan  14  or on opposite sides of the oil pan  14 , rather than the same side of the oil pan  14 . Further, the additional tube  126  may be sandwiched by metal sheets (not shown) acting as cooling fins, similar to the baffle  10 . The baffle  10  and additional tube  126  may be fluidly connected with the cooling system in either a parallel or series configuration.  
         [0037]    In yet another embodiment illustrated in FIGS. 8-9, a baffle  138  is shown including a first sheet, or an upper sheet  142 , positioned above the oil in the oil pan  14  to receive oil dropping from the engine. The upper sheet  142  includes an aperture  146  therethrough to allow passage of the oil pump pickup. The upper sheet  142  is supported by bosses (not shown) formed in the oil pan  14 , similar to the mounting configuration of the baffle  10  of FIG. 1. However, the upper sheet  142  is supported at an angle relative to a horizontal plane (not shown) passing through the oil pan  14 , such that oil dropping from the engine onto the upper sheet  142  is funneled to one side of the oil pan  14 . In the exemplary configuration of FIGS. 8-9, the upper sheet  142  funnels oil toward an interior surface  150  of a side wall  154  of the oil pan  14 .  
         [0038]    A second sheet, or a lower sheet  158 , is coupled to the interior surface  150  adjacent the upper sheet  142 . The lower sheet  158  may be coupled to the interior surface  150  by any number of different methods, including but not limited to: welding, brazing, fastening, utilizing snap-fits, and so forth. The lower sheet  158  includes a serpentine groove  162  formed therein, the groove  162  defining an inlet  166  at one end of the lower sheet  158 , and an outlet  170  at the opposite end of the lower sheet  158 . Since the lower sheet  158  is coupled against the interior surface  150 , a combination of the groove  162  and the interior surface  150  defines a passageway  174  to route oil therethrough. During operation of the engine, oil drops from the engine onto the upper sheet  142 , and is funneled into the inlet  166  of the passageway  174  by the upper sheet  142 . Gravity provides the necessary force to establish oil flow through the passageway  174 . By routing oil through the passageway  174 , the oil is cooled by contacting the interior surface  150  of the side wall  154 , which is air-cooled by the outside air surrounding the oil pan  14 .  
         [0039]    With reference to FIGS. 10-11, an oil pan  178  including a coolant channel  182  formed in a bottom wall  186  of the oil pan  178  is shown in combination with a baffle  190 . In one embodiment, the baffle  190  includes a metal sheet  194  having apertures  198  therethrough. Alternatively, the baffle  190  may be configured in a manner identical or similar to the baffle  10  of FIG. 1. The baffle  190  is positioned in the oil pan  178  to decrease turbulence in the oil and to substantially limit movement of the oil, such that the oil pump pickup remains continually submerged in the oil. Also, the baffle  190  is positioned to intercept aerated, or foamed oil from the engine before it returns to the oil pan  178 . Further, the baffle  190  allows time for the foamed oil to naturally purge itself of entrained air before falling through the apertures  198  and into the oil pan  178 . The baffle  190  may be supported in the oil pan  178  by fasteners engaging threaded bosses (not shown) formed therein. However, the baffle  190  may also be supported in the oil pan  178  by other methods, including welding, fastening, and so forth.  
         [0040]    The coolant channel  182  formed in the bottom wall  186  of the oil pan  178  is configured in a serpentine pattern and includes an inlet  210  and an outlet  214 , such that the coolant channel  182  is fluidly connected with the engine&#39;s (or a separate, independent) cooling system. Coolant from the cooling system enters the baffle  190  via the inlet  210 , and leaves the baffle  190  via the outlet  214 . However, the inlet  210  and outlet  214  may be reversed, such that coolant enters the baffle  190  via the outlet  214 , and leaves the baffle  190  via the inlet  210 . Coolant flowing through the coolant channel  182  removes heat from the bottom wall  186  of the oil pan  178 , which subsequently removes heat from the oil contained in the oil pan  178 . To fluidly connect with the cooling system, additional tubes including tube connectors  218  threadably engage threaded apertures (not shown) in a side wall  222  of the oil pan  178 . Like the tube  126  of FIG. 7, the coolant channel  182  may be configured in any reasonable shape or pattern. Also, the inlet  210  and outlet  214  may be positioned on adjacent sides of the oil pan  178  or on opposite sides of the oil pan  178 , rather than the same side of the oil pan  178 . The coolant channel  182  may be fluidly connected with the cooling system in either a parallel or series configuration.  
         [0041]    The exemplary baffle  10  of FIGS. 1-4 may be manufactured using conventional materials. In one embodiment, the tube  46  is made from seamless aluminum tubing to prevent leakage. The sheets  50 ,  54  are made from thin, aluminum sheets, and act as cooling fins to the aluminum tube  46 . Also, aluminum provides desirable heat transfer characteristics. Alternatively, the tube  46  and the sheets  50 ,  54  may be made from any metal, such that the heat transfer requirements of the baffle  10  are satisfied.  
         [0042]    In one embodiment, the tube  46  is configured in its serpentine pattern by a CNC tube-bending machine, and the tube  46  is subsequently sandwiched by the metal sheets  50 ,  54  during a sheet stamping process, utilizing a die and stamping machinery. Also, during the sheet stamping process, clinch joints  226  (see FIG. 2) may be formed between the metal sheets  50 ,  54  to interconnect the sheets  50 ,  54 . The clinch joints  226  locally deform the sheets  50 ,  54 , such that the sheets  50 ,  54  are permanently interconnected. As shown in FIG. 1, the clinch joints  226  are formed on opposite sides of the tube  46  to secure the tube  46  between the sheets  50 ,  54 . Alternatively, the clinch joints  226  may be formed on the sheets  50 ,  54  in any reasonable pattern such that the sheets  50 ,  54  are permanently interconnected, and the tube  46  is tightly secured therebetween.  
         [0043]    Rather than being formed during the sheet stamping process, the clinch joints  226  may be formed in a separate, independent stamping process carried out after the sheet stamping process. Also, the baffle  10  may be formed in its final, curved shape during the sheet stamping process. Alternatively, the baffle  10  may be formed in its final, curved shape during a separate, independent stamping process occurring after the sheet stamping process.  
         [0044]    As shown in FIGS. 5-6, the sheet portions  98  are integrally formed with one of the metal sheets  50  or  54 . The sheet portions  98  may be formed (the grooves and shape) during any of the above mentioned stamping processes, including the sheet stamping process, the stamping process forming the clinch joints  226 , or the stamping process forming the final, curved shape of the baffle  10 . Alternatively, the sheet portions  98  may be separately formed and coupled to the metal sheets  50 ,  54  via fasteners (e.g., bolts, screws, rivets, etc.) or via welding, soldering, brazing, or other like methods. Further, the tube connectors  70  are secured along the tube  46  by flaring the tube inlet  58  and tube outlet  62 , using conventional processes.  
         [0045]    The additional tube  126  of FIG. 7, in one embodiment, is made from seamless aluminum tubing to prevent leakage. The additional tube  126  is configured in its serpentine pattern by a CNC tube-bending machine, similar to the tube  46  in the baffle  10 . Further, the tube connectors (not shown) are secured along the tube  126  by flaring the tube inlet  130  and tube outlet  134 , using conventional processes.  
         [0046]    The baffle  138  of FIGS. 8-9 includes upper and lower sheets  142 ,  158  made from thin, aluminum sheets. Alternatively, the sheets  142 ,  158  may be made from any metal, such that the heat transfer requirements of the baffle  138  are satisfied. Also, the oil pan  14  may be made from aluminum to enhance heat transfer from the oil as it is routed through the passageway  174 . Further, the oil pan  14  may include cooling fins (not shown), similar to the oil pan  14  shown in FIGS. 5-6, to enhance heat transfer from the oil and the oil pan  14 . The serpentine groove  162  formed in the lower sheet  158  is formed by a stamping process. In addition, both upper and lower sheets  142 ,  158  may be stamped utilizing a stamping process such that no additional machining or forming is necessary in producing the final product.  
         [0047]    The oil pan  178  of FIGS. 10-11 may be die cast such that minimal machining is required to complete the oil pan  178 . The coolant channel  182  may be formed in the bottom wall  186  during the casting process. The oil pan  178  may be made from aluminum to enhance heat transfer from the oil as it is routed through the coolant channel  182 . Also, the oil pan  178  may include cooling fins (not shown), similar to the oil pan  14  of FIGS. 5-6, to enhance heat transfer from the oil and the oil pan  178 .