When do you change the fluid in the rear differencial. I was told by a mechanic that the rear differencial fluid was low and had metal shavings in it, and that the fluid needed to be changed and that it would cost $85.00 to do it. Does this sound right?

I'd say yes. The differential fluid is often overlooked by oil change technicians, even though it's something that should be topped off periodically.

It probably would cost more than that to repair it once it wears out.
Axle Housing Assembly Removal & Installation To Remove:

1. Lift the vehicle.
2. Drain the lubricant from the rear axle housing.
3. Remove the rear axle assembly from the vehicle.
4. Remove the brake caliper brackets from the rear hubs.
5. Remove the rear cover and gasket from the rear axle housing.
6. Remove the rear axle shafts from the vehicle.
7. Remove the rear differential assembly from the vehicle.
8. Remove the brake backing plates from the rear hubs.
9. Remove the rear drive pinion shaft yoke and seal from the drive pinion.
10. Remove the drive pinion from the rear axle housing.

To Install:

1. Install the drive pinion into the rear axle housing.
2. Install the rear drive pinion shaft yoke and seal onto the drive pinion.
3. Install the rear differential assembly into the vehicle.
4. Adjust the differential side bearing preload and the backlash.
5. Perform a gear tooth contact pattern check.
6. Install the brake backing plates onto the rear hubs.
7. Install the rear axle shafts into the vehicle.
8. Install the rear cover and gasket onto the rear axle housing.
9. Install the brake caliper brackets onto the rear hubs.
10. Install the rear axle assembly into the vehicle.
11. Refill the lubricant in the rear axle housing.
12. Lower the vehicle.

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I think that changing the fluid would take about an hour, and depending on the garage, and the labor rate, that they might elect to take the rear cover off of the differential, and drain it that way and replace the fluid once it was put back on. He could inspect the gears while the cover was off and tell you how bad it was.'

Do you hear any clunking or gear mesh noises from the rear when putting it in gear or running the vehicle?


Some mechanics would simply top off the fluid and wait until it wears out, which could be several thousand miles in the future.

Use gear oil for it of the recommended viscosity in the service manual.

Generally thicker than motor oil.

So, adding fluid would cost only the amount of the fluid plus some labor.
A bottle of fluid might cost $9.99 or so depending on where you get it.

You might be able to do this yourself if you crawl under there, remove the fill plug at the top, and just add gear oil. If there isn't enough room you might drive it up on some ramps and then crawl under there.