You indicate the engine ran well, doesn't smoke, cranks OK. If so, and the oil pressure guage was above zero hot idle, I'd leave the engine bearings alone. If the bearings are that worn, so are the pistons, rings, wrist pins, lifters, cam, drive chain, ad infinitum. If it wasn't knocking on startup, you're good to run for a while. If it was knocking on start or hot idle, pull the engine.
Add to this, getting a good clean fit while working under that truck is going to be a challenge.
Those engines will begin to smoke long before the rotating mass fails....assuming reasonable past maintenance.
Not worth going into and creates more failure points. Not enough access for clean inframe.
The oil pan and rear main seal will leak if the engine has crankcase pressure related to worn engine or PCV system faults. All crankcase vent plumbing and seals must be in serviceable condition for correct function.
Check the back of the intake manifold base for blown out sealant near the distributor for wet oil. BB 454 is famous for that blown out sealer and it'll create a nice oil leak and look like a rear main seal failure.
Be very careful with plastic connectors and brittle wiring.
IMHO and YMMV.
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Good news ---I finally finished replacing the rear seal job yesterday afternoon meaning everything is bolted back in place and operational.
I'm not going to lie ---that was a tough 1-man job. Took me +-35 hours to complete. Fitting the front differential, stabbing the tranny, twisting the transfer case back into place all the while laying on the ground mostly on my back swinging a free leg over to the jack handle to maneuver and pump-up/down the hydraulics...Made me stop and ponder several times --WHERE the hell are my friends?!, but I carried on.
Well I finally drove the truck a few times yesterday and today, several miles longer each round, and finally properly topped off the new tranny fluid level (small letters on stick --Do Not Overfill). The great news is the nagging engine oil leaks are gone. In my case the rear main seal and the oil pan gasket definitely were the main culprits.
Now the not so good news:
1. A large chunk of the internal "beehive" fell out of my catalytic converter while I was moving the exhaust back into place. Does anyone know of a good source for new replacement(s) cats? Keep in mind I'm in California (just answered my own question ---all my friends already left CA).
2. After replacing the oil pan gasket but before adding the new oil I removed the drain plug and a mixture of what I believe is coolant and oil poured out. The oil pan had been in place for approx 72 hours and during which time I'd estimate a small "shot glass" of this chunky goop had accumulated. Could it be that the intake gaskets and/or head gaskets are bad?
3. Hark, A mysterious new drive-train noise has emerged. Never a dull moment. A "sputtering" noise is how I would describe it. The noise only happens when I accelerate hard (under load) and comes on gradually at 2200 -2400 rpm. No sign of this noise If I ease into the 2200-2400 rpm range and beyond it. I think it might be an exhaust leak or maybe it has to do with the faulty catalytic converter. However what perplexes me is the engine is quiet (no sputter) with the tranny in Nuetral and if rev'd through 4000 rpm. Wouldn't an exhaust issue manifest in both cases (under load/no load)? Anyone venture to take a guess what might be going on here?
Any advice or tips appreciated on these three points. Thanks
