rear main seal speedy sleeve 3.5

[rjwig]

While trying to find a speedy sleeve for 2002 qx4 3.5 rear main seal, vendors (rock auto etc) don't have it.Skf has a large number of sizes.All-data has crankshaft specs. but lists main journal dia."dm"grade.Grade A,B,C etc.With different journal specs for each.Does anyone know what "dm" grade means?I would like to find a speedy sleeve in stock before I work on it.

[mdmellott]

The main journal diameter "Dm" grade means diameter main and refers to the specific journal grade A, B, C, etc based on the actual measurement of the journal. There are more than a dozen specific journal grade diameters for the main bearings but only 4 are needed for your engine. They may all be different or all the same part numbers depending on the actual measurements of each main bearing journal. For the main bearings this is a critical point since each consecutive grade only varies in diameter by .001mm and means a great deal when rebuilding an engine. As for the Speedi-Sleeve product, those are basically a one size fits all for their intended use. I still can't figure out why SKF does not list their part number 99331 as a fit for the QX4 when it is intended to fit the a Pathfinder that takes the same rear main seal. Something must be different or its an oversight on SKF's part.

[rjwig]

Thanks again for your input.