I was looking at the 4Runner tonight, and had a thought. Depending on what the ding turns out to be, I was wondering if it is possible to replace a bearing via taking the oil pan off and going in from underneath. Probably not, but just a thought.

 

I've done it on a 22R... required jacking the engine up to clear the front diff to remove the pan. I'm not sure you've got enough room to get the pan out on the V6. If you jack it up I think the firewall will prevent you from getting it high enough to slip the pan out. Good Luck!

 

Generally when the bearings are worn to a point that they need to be replaced, some level of crank damage has occured. It could be scarring, it could be general wear, requiring turn and oversized bearings... Regardless, replacing a bearing isn't a fix that you should expect will last you very long.

As far as I'm concerned an engine isn't rebuilt unless it the owner has full receipts and I can detail both the parts and machine work that went into the "rebuild". I've seen far too many motors that were honed, got new bearings, and sometimes new rings advertised as "rebuilt". They're just patched trash.

 

I had someone send me a PM about this last week I think. The answer is yes and no. You can replace all of the rod bearings by dropping the oil pan. The main bearings, you will have to seperate the transmission and move it back. Then jack the engine up alittle as mentioned in an earlier post. This will give you just enough clearance to replace these bearings. That's the only way to replace the bearings without removing the engine completely.

 

Ok so after reading all your posts i dived into mine this past weekend. Light knock sounding like it was coming from the top of the motor so im thinking lifters. How wrong i was. 3 were stuck solid and not any movement. The idiot before me that built this engine forgot to tighten the smaller 12mm bolts on the outer edges of the head and oil was spewing forth like niagara falls out of this thing. Needless to say i guess he had shares in exxon.
got the heads off to do the gaskets seeing as i had gone this far i decided to pull the engine and do a full gasket set, rings bearings and so forth. get the oil pan off and decided to wiggle No1 rod bearing and low and behold it moves freely. Pull it off and we have a spun bearing. new crank, Conrod, Bearings, Pistons..slapping the head, pins, oil pump, water pump, timing kit,overhaul the heads.....1300 dollars later and we should have a nice new engine for 60 to 100k miles.
oh well i only paid 500 for the 4runner 95 model and she is straight and rust free so even at this price i still have a very good truck with a fresh engine.