4200 Rear Sump Oil Pan
Our 4200 Rear Sump Oil Pan make it easy to swap this potent inline 6 into a wide variety of chassis.

The oil pan is an integral part of the 4200 block, we kept the wall thicknesses no thinner than what GM
used or in some areas the pan is thicker to allow better flow during casting.
Torque converter bolt access is maintained through the rear flange.

The pan is thick enough to allow tack welding in oil control baffles for competitive use.
A/C compressor boss machined but the hole is not drilled/tapped.


The pan has a number of features that need to be finished by the installer, this is done to allow maximum

Oil dipstick mount— not drilled to allow customization to clear header tubes etc.

The oil pan finish is delivered with "AS CAST FINISH" except the machined surfaces, installers should
clean up the oil pan using a 27grit flap wheel or glass beading. The foundry does perform some flash
removal. At a minimum solvent and high pressure wash the pan once the installer drilled holes are

Turbo oil drain Boss— suitable for 1/2 NPT return— not drilled.

An aux. boss behind the A/C boss is there to allow attachments of non-standard items such as a dry
sump pump etc.

Drain plug can be installed on either side of the sump. One side is drilled/tapped for the drain plug.

Pan dimensions :  Sump is 7.25” deep from the pan rail to the bottom of sump

Front of the sump is 12.3 “ from the transmission flange

The front section of the pan is 2 3/4" deep from the flange to the bottom outside of the pan, just in front of
the sump the pan is 3 3/16" from the pan ran to the bottom outside of the pan.

Holds 5 US quarts, additional oil could added.

You will need a modified 3500/3700 oil pump pick up to sit mid-sump. When in stock a used oil pickup
is available for US$30.00 (provided in  AS IS condition). Additional mounting holes for the pick up tube
will need to be drilled/tapped (6mm) in the main cap girdle.

The original oil dipstick hole needs to be blocked off—a 1/8 NPT plug works well.

Use Permatex “Right Stuff” to seal the pan to the block.

The 8mm OEM bolts will need to replaced with M8x1x35mm Allen head bolts/washer (not included).

Details are in the installation guide provide with the tracking number for your shipment.

GM 78 to 87 A/G bodies will require a 3/4" to 1 1/4" notch in the cross member to clear the pan. This is
due to the firewall to crossmember distance.
Dec 3 2018 Update

Oil pans are in stock and shipping.  Accepting orders now.

Email for ordering and payment details.

Payment via bank draft or paypay (you cover the paypal surcharge).

We pride ourselves on providing personal service for our products.

Note: The lower bell housing bolt holes (4) are not
yet drilled in rear flange of this pan. The pans are
supplied with these holes drilled.
Dipstick boss
Turbo oil drain boss