3.1 transmission interchange question

[Boneyard]

I have a 2002 SE 3.1L and am having transmission problems. Will a tranny out of a 2000 or 2001 SE 3.1L be the exact same thing? In other words swap and drive?

[richtazz]

According to GM, your 2002 is aa one off trans. It has the same final drive ratio of a 2001, but the tag code is different. You'd be best off calling a salvage yard, as they have Hemmings manuals that tell what parts interchange between cars and years.

[Boneyard]

so is there a chance that it will interchange? what about off a 2003? If i'm getting a hard shift sometimes, would that indicate bad tranny problems? it doesn't always happen, but sometimes. thanks again for the help

[wafrederick]

It wil fit,check the color of the plug if it is the same.If they are not,the electronics have to be changed.The final drive has to be switched too if the gear ratio is not the same.These are two things to change.Is the neutral safety switch internal or external?This is another thing to check.The 4t65Es do not have a lot for interchanges,these changes I mentioned will be needed.I have done the changes,the final drive and the electronics which the transmission will work if done right.

[Boneyard]

how do i check for proper gear ratio on these tranny's? Does the hard shift sound like a common problem with these transmissions? It will do it for a while, then go away, then come back sometimes in the same day. usually changes after the car has been shut off and restarted. thanks again

[tblake]

boneyard, hard upshifts are a common problem on these trans's and usually dont mean the trans is shot. In fact, the common fix is a DIY job that basically only requires a simple pan drop...

See this thread in our tips and maintenance supforum.

http://www.automotiveforums.com/vbul...d.php?t=920671

Wafrederick, see Rich's post, he shouldnt have to swap the final drive's and only the 2004+ 4t65e's have internal PRNDL switches.

Rich, didnt the 2002 and 2003 4t65e's have the redesigned PCS solonoids? Maybe thats the reason for the different tag numbers.???

[richtazz]

I think so Tim. It's very possible that an 01 or 03 trans would work in the OP's car, but I don't want to say yes and not be sure. I don't guess and/or spew forth nonsensical drivel like some people....

Not to change the subject Tim, but did you see Bob's new car, check out the mileage poll thread if you haven't.

[tblake]

Bob Didn't! NO WAY! Oh Man!

They are nice cars!

I was a little scared that he bought a different model.

[wafrederick]

It is a good transmission,the spider gear pin does break sometimes because someone hot rodding it and spinning the front tires.There is a rectangular tag with two big letters and the third is on the tag too in the smaller letter and numbers.

[wafrederick]

Some 2002s had the neutral safety switch that is internal.My father has one in the back room out of a 2002 Buick Lesabre that is internal.

[tblake]

Hmmmm, I did not know that.

That is the dumbest thing GM ever did, there are enough problems with the PRNDL switches, and then to put them inside the trans...

Imagine your problem is a PRNDL switch, and to replace it you need to remove the trans and disassemble it. (or can it be accessed by taking the side cover off). I've never worked on a newer 4t65e.