Transmission change do I need to relearn the pcm
 

Hi,I'm having a issue with my 96 suburban 1500 4x4 5.7 a/t.I just recently changed the old transmission for a used one with low miles due to metal in the pan on the old one and mager slipping.My problem is now that the new trans is in with new fluid/filter seals ect. it wont shift after 2nd gear or thats what it seems like.(Story line) put it in reverse hits good back out switch to (D) drive hit the gas to go so it go's like it should then around 2500 rpm boom another shift straight in like what seems normal then as im going it just wont shift after that I can get up to around 25 to 30 mpr then I have to put it 2nd 2 on selctor tried 3 but nothing happens just revs n revs it will go about 50 -60 mpr but rpms are at 4,000 almost red line.Is this limp mode?I've done everthing by the book as far as dropping the pan and checking all sillynoids tcc also topping off too.Note the trans fuse # 20 is not blown.I did talk with my uncle today and he said something about having to relearn the pcm is this true i hope so hate to do it all again.(Note)before test run did the 75% fluid then switched though all gears several times the all seem to hit like normal in this order N R N 1 N 2 N 3 N D repeated 3 or 4 times and then again at max fluid level )
-Thanks any help would be much much apprecited-

could there be a problem with the wiring harness going to the computer,can the dealer reflash the computer,maybe the computer is good but not recieving all the info from the trans to know to shift it


Sean
97 4x4 burb

Hey thanks for the reply I checked all the electric contections all look good.I am getting a code for p0151 o2 sensor bank checked all those conections also good the wire for the rear o2 was alittle melted wear it goes over the cat. but inspected it and rewrapped it with exhast tape.Is the another fuse in the truck other than the trans fuse in the interior fuse box.

there's another 20 amp fuse in the engine compartment i think its labeled ENG 1,as for the trans i think AAMCO has a service thats check the trans thru the computer from what it looks like that trans shifting is done by the computer,do you have any junk yards near by maybe try a used computer if you get a good deal on one



Sean

97 4x4 burb

Hi, was there any solution to this problem. My 96' Tahoe is doing exact same thing.

It was just a bad trans stuck in limp mode.You need a new transmission.If your in the bay area,ca I do them for 350.00..