Re: While both you and Clem are probably
Mark-----
Well, it's possible it's (1). As far as (2) goes, GM's instructions are in the OVERHAUL manual. Presumably, they figure an "overhaul" is going to happen at at least 50,000 miles, if not much more.
(3) is a possibility. (4), I doubt. Like I mentioned, rear main seals are very often replaced in service, between overhauls. Rarely, is the rear main bearing replaced with it. In fact, I'll bet that GM has replaced tens of thousands, if not far more, of rear main seals in 2 piece seal engines over the years and under warranty and I'll bet that dealerships are not even authorized by them to replace the rear main bearing at the same time. I've never heard of a single case of someone having bearing problems after a rear main seal change.
As far as I am concerned, if I have a bearing cap off, rod or main, I replace the bearing as a routine matter. As you say, bearings are cheap (although, not so cheap if you buy them from GM which is the easiest source of INDIVIDUAL main bearings not packaged and sold as a set). However, while I do this, I don't think that it's absolutely necessary.
Mark-----
Well, it's possible it's (1). As far as (2) goes, GM's instructions are in the OVERHAUL manual. Presumably, they figure an "overhaul" is going to happen at at least 50,000 miles, if not much more.
(3) is a possibility. (4), I doubt. Like I mentioned, rear main seals are very often replaced in service, between overhauls. Rarely, is the rear main bearing replaced with it. In fact, I'll bet that GM has replaced tens of thousands, if not far more, of rear main seals in 2 piece seal engines over the years and under warranty and I'll bet that dealerships are not even authorized by them to replace the rear main bearing at the same time. I've never heard of a single case of someone having bearing problems after a rear main seal change.
As far as I am concerned, if I have a bearing cap off, rod or main, I replace the bearing as a routine matter. As you say, bearings are cheap (although, not so cheap if you buy them from GM which is the easiest source of INDIVIDUAL main bearings not packaged and sold as a set). However, while I do this, I don't think that it's absolutely necessary.
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