2000 blazer 4x4 lost power to drivetrain going down the highway. No noise it just stopped getting power to the wheels. Coasted to a stop. No gear does anything. Engine drops in rpm a little when putting it in gear but nothing happens. Seems to be freewheeling almost. Revs down slower but not really slow or anything. Thought the transfer case chain went but then I would have 2 wheel drive still I believe. It's like the flywheel came unbolted. I don't have it home yet so just going though the research bit before I get it home today.
Answer: You are correct- if the transfer case chain broke, you would still have normal 2 wheel drive. If the engine has power, but not power to the wheels, then there are only a few things that can cause this.
1. The transmission had a major failure. If something broke inside the trans, then this would be the result. It could be anything from a valve sticking in the valvebody to a failed band or clutch pack or even a broken shaft. If something like that happened, you may not have even heard it when it failed.
2. The torque converter may have failed. This is the part that connects the flywheel to the transmission. If it has an internal problem, it would not transfer engine power to the transmission. This is not very common on the Chevy Blazer though.
3. The driveshaft or a U-joint broke. If that happened you would have heard a loud noise of some kind though.
4. A failure in the rear differential. If the ring gear or pinion failed, there would be power from the transmission to the rear end but it could not power the wheels. This may also have been accompanied by a loud noise when the failure occurred.
Chevy Blazer Rear End Noise
2005 Chevy blazer rearend made loud pop then has noise like the gears are not meshing right. Dont do it as much backing up.
Answer: If you are sure the noise came from the rear ends, then the first thing you are going to have to do is remove the rear differential cover and see if there is any damage to any of the gears or bearings. Look for metal flakes in the gear oil. If so, then repairs internally will be needed.