i recently bought 2000 4x4 2dr blazer. it was good for 3 weeks and then one day i couldnt reverse from the parking lot. all the other gears work but i really have to push to car to get into the reverse. please help

 

Are you sure that all other gears are working. If the reaction sun shell stripped in the transmission, it would knock out reverse, 2nd, and OD.

 

it works fine and idont have OD on my blazer. i think

 

Yes, you do have OD (over drive). Your truck has the 4L60E transmission which has four forward gears. How many times does it shift when you are moving forward getting up to speed?

 

it shifts 4 times. on the dash boards says 1 2 3 D N R and P by the way i talked to mechanic today and the guy told me that i lost my neutral and the reverse and he wants to rebuild my transmission for around 1500$ i wanted to hear your opinion about this thank you for your help