Queries :: Query With Too Many Groupings

I have a report that lists the quantities used of each of the filters required for our vehicles. In other words, if we have 8 vehicles using Oil Filter #51036, then the report would read Filter #51036 = 8ea.The reports work OK now, but I am having trouble with one line, the brand.My goal is to have the report look like this:Oil Filters (Number) // Brand // Quantity..Here is the SQL that I am currently using for the Oil Filters query:

Code:
SELECT Parts.PartType AS [Filter Type], Parts.PartDetails AS [Filter Part Number], Count(ServiceSpecs.OilFilterPartID) AS [Count Of Filters Used], Parts.PartBrand AS [Filter Brand]
FROM ServiceSpecs INNER JOIN Parts ON ServiceSpecs.OilFilterPartID = Parts.PartID
WHERE (((ServiceSpecs.OilFilterPartID) Is Not Null))
GROUP BY Parts.PartType, Parts.PartDetails, Parts.PartBrand;

The problem is that the query is "Grouping" by [Filter Type], [Filter Part Number], AND [Filter Brand]. That means that only one brand will show at a time.