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Vehicle speed sensor on replacement transmission

Hi everybody,
I’m replacing the transmission in a 2008 uplander. I have the replacement transmission all bolted up, and now I noticed the electrical plug on the passenger side doesn’t fit. Searching online it looks like the plug is for the vehicle speed sensor.
So now I’m looking for some advice.
I can buy a different speed sensor from a parts store, but I’m wondering if I can just file the connector to make it fit.

All I can say is look here.,2008,uplander,3.9l+v6,1441146,electrical-connector,vehicle+/+output+speed+sensor+connector,15798

And see if you can find anything that looks close.


Thanks GM!


Thanks Tester. The piece rockauto sells matches my old transmission.

It looks like if I cut the ears off my plug it will fit and still lock.
Worth a shot? Or bad idea?

When it comes to this iffy stuff?

I try to keep things local.

That way, if they mess up, you can look them straight into the eye.


I don’t mean to sound like a total jerk, but here goes . . .

It appears you didn’t install the correct transmission

At the very least, it was from a different model year Uplander

Worst case scenario, it’s not even from an Uplander, the gear ratios are wrong, and so on

Correct me if I’m wrong, but it appears you’re installing a used transmission

Pulled from a vehicle?

Or pulled from the shelf?

Who located the part for you?

How was it verified that it was correct for your application?

And who did the verification?

1 Like

When installing a used transmission or engine I remove all of the sensors and switches within reason from the old unit and install them in the replacement.

It is a used transmission. The salvage yard pulled it.
My bad for not looking it over closer when I picked it up.
The main wiring harness matched up, as do all the other bolts and connections.
I gave them my old tranny for a core.
At this point I’m far enough along installing it, I might as well finish and see if it works.

There must be a part number embossed on the transmission housing. What is it? Maybe we can cross reference it to see if it works with your engine and electronics.

Embossed on the driver’s side is 24211956 f 38
There is also a sticker and a metal tag that both have 24236695

The first number is the housing part #. See if you can find 4T65-E M-15, or a similar M number. The Uplander had a final gear ratio of 2.92:1. There are over 30 different 4T65-E applications, and 10 4T63-E HD (heavy duty) applications. It’s not surprising there might be different connectors. If it is a 4T60-E, it is not the correct transmsission. That was used in an earlier generation of GM transmissions in the mid-1990s.

Good info.
Also would help to check glovebox label to find out which one it was built with.
Just for some additional background-

Call the salvage yard and ask them.

I don’t see the 4t65 number anywhere but I just called the salvage yard and they said they pulled it from a 08 uplander, same as mine.

Obviously, it is not identical and you’d be smart to verify exactly what you have now vs what was supposed to be in your Uplander.

Assuming all is well, it’s unlikely the junk yard will sell that wire harness and considering your trouble, they may just hack that connector off for you. Then you can either splice it into yours or preferably, if you have some skills and time, extract the pins and swap the housings…

Not that I know anything about it but assuming the rest of the transmission will work, wouldn’t just putting a new speed sensor in with the proper connections be cheaper and easier? They are only about $20-30?

Interesting… looking on Rockauto there’s an input speed sensor and an output speed sensor.
They seem to look like the two connectors in the OP:



Wow, I finally found the problem. Part of the plug stayed in the transmission from the junk yard. Pulled it out and all is well. Sorry to trouble everyone with something so stupid. Thanks for all the help.


Great to find out. I’ve been pondering this.

Speaking of stupid stuff it reminds me when I did a thorough carpet shampooing of my old Riviera. I took the seats out and when I put everything back together it wouldn’t start. After hours of trying to figure it out I had to have it towed to the shop. They said it was a missing fuse. How could that be? At any rate I said I felt really stupid not finding it and he said don’t feel stupid, it took our best guy an hour to find it. Can’t remember what it cost me but the car was clean anyway. So don’t feel stupid.

been there, done that, lol

Thanks for reminding us to check for missing parts. Maybe next time I’m in a similar,situation, I’ll remember to check the item I removed to make sure I pulled everything I need to put the new one in right.