Allison spin on filter???

Look at eBay 280122076625.....3 Allison brand filters for Duramax...with shipping they're about $13 each.

I bought mine at the dealer. The aftermarket filter did not have the same hole pattern and would not allow the oil to flow freely past the magnet that is movable to the new filter. I've heard some do not have the magnet, but wanted to keep it there as insurance since it was that way from the factory. It's only a few dollars more.....

An actual Allison brand filter IS the OEM part, with the magnet, matching holes and all.. AC Delco and Allison don't make their own filters, they're jobbed out to the major manufacturers and built to spec with appropriate labels and color.