dstanford

my 2000 silverado has a 4l50e transmission that went out so I bought a rebuilt,after installing it I only had first gear,so I pulled the wiring harness and all the electrical out of my old transmission and cleaned them real good and installed them into the rebuilt unit,now I have all gears except third,I would start going and get my speed to 20mph,let off the gas,the rpm's drop and it shifts into third,I drove the truck about 80 miles,the next day I drove it and I noticed the rpm's climbing and my speed dropping,so I drove back home but in third gear,so I pulled the servo out of my old transmission and swapped it with the one in the rebuilt transmission,now I have first,shifts into second nice but nothing else works,reverse ,first,and second is all I have now,could the servo out of my old transmission not be letting the transmission shift into third,both servo's had two groves on the tip of the servo pin,so their the same in lenght