Ok I've got this good running 1992 Ranger Extended Cab 4x2 4.0 automatic that has 108,000 miles. We're the second owner. I've done quite a bit to it to get it back to being reliable since it say up awhile before we bought it for $400. Everything's working good now except some oil leaks. I tried 3 different times to fix the front crankshaft seal but even with a new Ford seal it still leaks just as much. Now the majority of the oil leaking is from the rear main seal. Maybe a little coming from the back of the valve covers. A shop told me he would change the rear main seal for $225. But I'm wondering if the front seal didn't seal will the rear main seal stop leaking too. Usually that means a work crank bearing surface. So we're going to keep this truck, it runs and drives great. But is it worth getting just the rear main seal fixed for now or wait until it gets really bad? I'm having to put 1-2 quarts between 3,000 mile oil changes. I use Motorcraft 5W-30 oil. I thought of trying 10W-30 but didn't think it would make a difference.

 

I thought I had a bad rear main, turns out to have been a leaking valley gasket and some leaking valve covers. They quoted me $350, but I also had them R&R the clutch while it was out. ALso found that the oil pan gasket had leaks. Overall cost me $700 but I also had them install new master and slave, new oil pan gasket and new oil pump while they had the pan off. Now is leak free. So I would have them re-analyze the leaks. We redid the front oil seal when I had the timing chain etc replaced.

Truck has over 300000 miles and runs great. So if I was you I would go ahead and put a few $$ in it if it is a good runner and drive it. The truck had 65000 on it when I bought it for my son to go to school with.

 

With the vintage of the vehicle & no more mileage than it has on it & with the oil consumption/weeps/leaks no worse than reported, check/re-torque to spec, the valve cover fasteners & have a look at/change the PCV valve. If it's sticking closed, or if it or its hoses are clogged up, it'll cause excessive crankcase back pressure that can force oil past the weakest seal or gasket. If the engine is clogged up with varnish, gum, or sludge, the piston ring pack may also be stuck & causing excessive blow by & that can cause a crankcase over pressure condition, that by itself, or in addition to the above PCV woes, can Really put the hurt on seals & gaskets.
A pressure gauge with a special fitting can be attached to the valve cover oil fill cap position, that'll measure that crankcase pressure, if you come to suspect excessive blow by, or an acting out PCV system.


If you come to think the ring pack, or engine is mucked up inside, or the crank shaft seals have hardened, shrunk & are weeping, maybe consider a high mileage recipe engine oil.
Valvolene MaxLife semi-syn 5w-30, that also meets Dexos-1 & has a lower NOACK % evaporation than the Motorcraft, is thought to also have ester oils in its recipe & has been successfully used by a lot of folks to condition seals to diminish, or stop seal weeps/leaks, free up ring packs to improve compression & tidy up an engines innards of varnish, gum & sludge.


If the engine has a deposit load that can be seen on the top end, be sure to use the specified FL-1A oil filter, or a like one that is known to have a lot of media surface area & is known to have lots of dirt holding capacity & run a couple of short fci, until the engine visibly cleans up inside on the top end & see how the blow-by & seal weeps/leaks go.
Some thoughts for consideration, let us know how it goes.

 

When I got the truck it had 104,000 miles on it. It sat up not regularly driven from the previous owner but not years and years of sitting. It was driven but just not on everyday basis. Since I've gotten I've done a full Motorcraft tune-up plugs, wires, pcv, fuel filter, air filter, coil pack, fan, fan clutch, fuel pressure regulator, fuel pump assembly, fuel filler neck hose, driveshaft center bearing support, brake calipers, rotors, pads, shoes, wheel cylinders, front brake hoses, used ABS module, and tried to change front crank seal 3 times. The mechanics in our area aren't really diagnosis mechanics but just parts swappers. Maybe one or two good shops that have the knowledge to diagnose. So in order to find out where all the oil is for sure coming from do I need to take it Ford? Or do I just need to replace all the gaskets/seals? The only one I can tell isn't leaking is the oil pan, which is good because you have to remove the engine to change it.

 

You have to loosen the motor mounts and lift the engine up, you do not need to pull it out, thats how they did mine. Need just enough to allow the pan to clear the front cross member, but my trans was also out so that helped. The seal at the front of the pan can cause a lot of leakage as part of the pan gasket is what covers some of it, at least on mine.

I think there is a state organization associated with this site with membership etc. Look at that as a possibility to finding a shop. Also maybe in southern tenn? Nashville should have something. Like I said I paid $700 and they did all the gaskets (I provided the parts) so maybe you can find someplace to do like wise?