Thank you for you question.
I am sorry you are having a problem with the snow blower. If you have replaced the chain and it is still slipping I recommend making sure it is the chain slipping and not the friction wheel. The friction wheel can cause the drive on the snow blower to feel jerky almost like a chain jumping teeth. If the problem is confirmed to be the chain, I recommend checking the bearings on all of the shafts. If they are worn, the chain is not held tight. I would replace the bearings on both sides if you find any worn. You will need to check the bushings for the wheel axle also, it they are worn the chain will be loose. If you are going to replace the bearing, I recommend removing the friction wheel because it will give you more room to work. If the friction wheel has any nicks or flat spots, I would replace it also. It is better to do the repair once that twice. The owner's manual usually has the instructions for removing the friction wheel towards the back.
In some cases, I have seen all of the bearings to be absolutely fine but the chain still jumps. This happens if the chain install was too long. You might have enough slop in the chain to remove one link.
Please let me know if you need further assistance.
Here is a link to order any parts you need.
Sears Parts Direct
If you do not feel confident repairing this problem yourself, then you can have it repaired at your home by a Sears technician. Here is a link for the website:
Sears Home Services
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