Hoe many hours does a flat rate manual give to change a front wheel bearing on a 2004 Buick Lesabre

I can't answer but suggest you try this since few mechanics are on this desk. http://www.laborguide.net/

ALLDATA subscriptions can easily run $2,000 per year for that information--nobody, here, has access that I know of.

Most wheel bearing/hubs on FWD cars will last 100,000 miles. Are you sure your wheel bearing/hub needs replacing?

I think the link I gave has a 45 day free offer.

I replaced the front wheel bearing/hubs on my 2000 Taurus 6 months ago (104,000 miles). It took me about 5 hours per wheel. With all the pullers required (splined axle, ball joint, tie-rod end), and lowering the subframe, there's more to it than you would think. It's all a function of how a car is configured.

I had a mechanic drive it and we really think it's a wheel bearing and not a cv joint. The car has 70,000 miles on it and I agree the bearing should last longer.

Here is my writeup of that experience:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-9.html#post1691894

Front wheel bearings are usually beefier and last longer than rear wheel bearings.

You are "coming into the zone" when wheel bearing and suspension parts, in general, need to be replaced. My Taurus just came out of the zone, where I replaced all four wheel bearing/hubs, front and rear struts, sway bar links, outer tie-rod ends, sway bar bushings, and A/C compressor. Now, I should be good for another 100,000 miles.

Hoe many hours does a flat rate manual give to change a front wheel bearing on a 2004 Buick Lesabre

The MOTOR Labor Guide says it takes about 1.3 hours to replace one hub assembly on your vehicle; I'd figure about an hour and a half, if you have the right equipment.

The newer GMs are notorious for the wheel bearings wearing out; I find 70,000 to be a little unusual but not completely bogus.

While we may have access to current labor/time guides, it's tough to come to an accurate quote without knowing more about the vehicle and operator.
I used to. Too many times challenged... and by the wrong people.
Too many variables to do that. Regional variations, as well as driver's habits, etc.

What you need to determine from any estimate you're given is if the vehicle in question is worth the cost. Only you will know that...
Not only this repair, but the next one as well.
Tell here what is going on and what has been diagnosed.
What else is wrong with the car and what do you expect from your car...