P0730 – Incorrect Gear Ratio?

If you have already dropped a replacement transmission into the Cavalier, why think about putting in another rebuilt? It may be that a couple of adjustments will fix things for you.

Here’s what I would suggest based on the 0730 error code:

1. Contact the shop where you had the work done
2. Ask them what their warranty period is on the transmission
3. Ask them to retrace their steps on the replacement
4. Ask them to redo the work so it is done correctly

Okay, so you are probably wondering why I am asking you to have the shop redo the work and it is a good question. I honestly think that when they reset the input and output shafts they somehow slipped out of position.

The 0730, as you might imagine, is a transmission error (07 pair is a giveaway). In this case, it is showing a variance in the rotations between the output and input shafts. This means the tranny will slip almost automatically, no matter what sensors and other parts you replace.

Indeed, this type of error can easily damage the clutch/band assemblies as well as putting stress on the gearing. You can see, then, why I am suggesting that the work be redone. Indeed, they should also replace any sensors or solenoids that also have to be replaced on their nickel.

Believe it or not, I am not slamming the techs who did the work because this is a rather tricky set up and it can easily be knocked out of alignment as other parts are replaced in the transmission as it is rebuilt.

If the shop won’t take care of that work, then I would suggest asking them to put a rebuilt in, splitting the cost with you as I think it is the fair way to handle things.

Please let me know what happens.