4g63 Billet Rear Case (6-bolt DSM Rear Main Seal housing)


The FTY Racing 6-bolt billet rear case is a bolt on replacement for the original rear main seal case found on the 1990-1992 6-bolt 4g63 engines. This new housing simplifies the original case by removing the oil seal separator, increases strength of the oil pan bolt bosses and adds additional clearance for aftermarket flexplates in automatic transmission applications.

Normally: This item is not on the shelf ready to ship, it is machined to order. Expect a 4-6 week lead time after you place your order before the item ships out. Thanks for understanding!

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Designed at FTY Racing in Michigan, the FTY Racing billet rear case for the 6-bolt 4G63 was created to improve upon the OEM design. We did a few things that are different than the OEM case:

  • We’ve machined our part from 6061 T6 aluminum. Our design is less brittle than the factory rear case and has additional reinforcement around the oil pan bolt holes, which we’ve broken ourselves and found broken on most of the engine cores we have disassembled.
  • We’ve updated the oil seal so that it presses into the case from the outside. This has allowed us to remove the stamped oil separator from the OEM design, which simplifies the part.
  • We’ve updated the bottom of the case where the oil pan mounts for additional clearance for SFI certified flex plates like the one available from our friends over at Kiggly Racing.

This purchase is only the base case – Add a new oil seal (MD343564) and gasket (MD183243) or a Fel-pro rear main seal set (BS404081) and you’re ready to bolt this new case up to your next build.

Please Note: We produce these individually. We don’t have these on the shelf and we make your part after you place your order, so expect a 4-6 week lead time before shipping. If it’s longer than that, we’ll let you know so that you can plan accordingly. Thanks for understanding!

Additional information

Weight 1 lbs
Dimensions 7 × 4 × 1 in