I would agree with Will: you don't want 3 quarts of oil do the work of 4. 
Derek, could it be that your temperature sensors read higher with more oil
just because there's more of it. For example, if it's the dipstick kind,
it will be in contact with more oil.

Sami

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| Sami Dakhlia                                       Voice: (314) 935-5670 |
| Department of Economics, Campus Box 1208             Fax: (314) 935-4156 |
| Washington University                                                    |
| One Brookings Drive                                                      |
| St. Louis, Missouri 63130-4899                  dakhlia@wuecona.wustl.edu|
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