2009 Prius - Revving sound??

In terms of the actual work required, it's pretty much exactly 2✕ the work to do two.

Now that doesn't necessarily mean a mechanic who would like to sell you more work won't offer some discount (maybe charge for 1.8✕ the work instead of 2✕) in order to persuade you. That can be a savvy sales move whether or not there's really less work involved.

And if you get offered that kind of a discount to do two bearings, and you want to do two bearings, then by all means accept the discount.

It's hard to generalize how long the things last. It's generally a long long long long time. But that can be affected by a lot of different things ... how many hard pothole hits each corner of the car has taken ... if there was a dragging brake for a while in one corner that heated the hub and cooked the grease ... etc., etc.

The bearing manufacturer can probably quote you a "mean time before failure", but it's one of those situations where the variance is so high (the bell curve around the mean is so broad and so flat) that, combined with the fact there's no real work saved doing more than one together, it's pretty reasonable to just let each one wear out whenever it's going to, and replace it then.

 

Certainly the dealer offering an oem bearing installed with warranty for $575 is an equivalent or better deal overall than the independent at $1048 divided by two. The dealer has effectively matched the independent price. He still has a lot of margin left at $575.

As long as you are really going to replace the car as soon as the new one comes in. You will certainly make several thousand more on the trade. If you might fall in love again with the current car because it drives so good, I might go with the independent. You are likely to need him in the future when the real bills start coming in.

 

I've noticed, after battery disconnect on my 3rd gen, the next few start ups (3 or 4) there'll be an odd rev-up, for just a few seconds, just after start-up. I've attributed by experience at least, to the car's computers needing to do some recalibration.