We are the original designers of the true two piece diff covers. We build our gear portion of the cover from one piece of 1/4" plate that we form 8 different ways on a cnc press brake. We then fixture weld our covers to a 1/2" thick bolt ring. Finally we add a machined fill bung w/ 3/8" NPT pipe plug (which gives you a 5/8" diameter fill opening).
We have several different options including
-upgraded armor of 1/2" plating up the ring gear for use of mounting rams and such to the face of the cover
-Counterbored mounting holes for use w/ socket head cap screws
-integrated drain where we stand the cover on edge and machine thru the side of the 1/2" bolt ring and tap it for an 1/8" NPT pipe plug.
-lower 1/2" plating where the bottom portion of the cover is plated to w/ stand severe abuse of competitions such as XRRA
-Tread Plate instead of the standard smooth 1/4" plate
-upper tabs extending from the 1/2" thick bolt ring to attach trusses or upper lik tabs to.
And just about anything else you can dream up
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