So I replaced a the 3.0 V6 in my 2008 Ranger XLT with a re-manufactured one. Before the replacement it had no leaks anywhere. Once the engine was replaced it now has a moderate leak from the back of the engine. The replacement engine had a rear main seal installed already, so I did not replace it. My question is whether the 3.0 V6 engine flywheel/flexplate bolt holes are open to the crankcase like in many Ford V8 engines. You have to put RTV sealant on those V8 engines around the bolts to keep them from leaking. So I was wondering if you are supposed to do the same for the 3.0 V6 engine. The most likely problem is either the new rear main seal is leaking or those flywheel/flexplate bolts needed to be sealed.

 

Assuming oil leak not coolant leak

Have ran into that on some engines but 3.0l does not have that, holes are centered on rear journal so can't be drilled thru: https://i.ebayimg.com/images/g/1jYAA...1Pw/s-l400.jpg

Can be main seal leak, there is no way to test it after installing it, beside running the engine
Can also be the rear cam cover, it should be sealed with RTV when installed: https://cimg3.ibsrv.net/gimg/www.ran...1d8a71754.jpeg

 

It's possible they didn't use any RTV at the edges of the rear main bearing cap where it meets the engine block above the oil pan. The oil pan gasket is not enough to seal those crevices and is a sure-fire leak spot with no RTV.

If this is the case and you have a Torsion Bar Ranger, the pan can be dropped (may need to remove front axle if 4x4) and this can be remedied. If you have a coil spring truck, the engine crossmember is MUCH closer to the oil pan and I'm not sure if the pan can come down far enough to access this area. You may need to lift the engine to gain enough clearance to drop the oil pan. It may also help to slide the transmission back. Obviously, this can turn into a can of worms quickly, because you'd have to watch the torque converter and make sure it stayed seated to the front pump, or else you would have to reseat the torque converter.

 

It is definitely an oil leak, not coolant.

 

The original long block did not have the oil pan installed. I installed a new oil pan and oil pan gasket without using RTV. My bad. The multi-use gasket looked like it had enough rubber to seal, but I guess it didn't. Thanks for the response.