I have an 02 aztek, yesterday my spedometer started to go crazy and it doesn't like to shift properly I was on the highway and I was going approximately 70mph but it said I was going 30-40mph

You will have to change out your speedo with one from a salvage yard. Your vehicle will continue to not shift properly it the speedo and tach are not functioning.

Do you think that is the only option I have?

Also I was reading about the bcm. I'm really hoping it not that

I would say yes. I'm a Toyota guy and when the gauge clusters fail, they will not shift properly until replaced. The computer takes all the info from the cluster in order to shift at the appropriate time. If no info is coming in, it cannot shift at the right times. Is your check engine light on? If it is, get the codes read. You may have a bad VSS. (Vehicle Speed Sensor). If no codes, I would replace the speedo.

Usually if the BCM fails, a great number of other things will fail also. Like dash lights, radio, windows, etc. It controls more than one thing.

Thank you. Everything else is working except for the issue I mentioned. There is no check engine light on. Is it safe to drive or should I wait cause I have to go to work and take my son to school. Also is it easy to change of I get a new one?

It may shift goofy, but if it's the only ride you have, you got to use it. Try shifting gears manually at slower speeds.Never changed one out on a Pontiac. They usually aren't too bad to do. Check youtube for a video. Or if you pull one from a salvage yard, you can figure it out on the junker before trying it on your own.

Thank you very much

Did that work for you? Or not? If not it's the BCM or body control modual which has 100% fail rate on these cars. I just spent 90 at the dealer for a diagnosis I got from AutoZone for free. Told me it would cost 810$... I found the part on Amazon for 154.00 and the youtube video that shows you how to change it out, time consuming but not 550+ in labor. Once it's replaced, the car must be reprogrammed, fortunately it will still drive once that has been replaced soyou can take it to an authorized dealer, cost anywhere between 90 and 120. Still much better than the alternative . Seems like this should be a cost absorbed by the company, but I guess making an extra grand for every aztek on the road is good for their bottom line... Hope this helps other aztek owners whose car has gone full Christine on them.

It was my transmission. I got a different one put in and now it runs and the Speedo works fine.

I have a 2002 Pontiac aztek, with the same problems, don't, do not, please don't try fix it unless you ready to spend alot of money and time for nothing, trust me sale now,

I spent $1200 on a tranny and the problem went away. My spedometer works and no more jerking. Thankfully it worked.

My Aztec is having the same issue but when I let off the gas it goes into neutral. How do I stop it from doing that. I have to get to work