speed sensor

where would the speed sensor be located

Depends on which sensor you are refering too.
As thier is wheel speed sensors, and a speed sensor on the trany too.

It would also help to know what year of car, engine, etc you are talking about.

it a 2000 gt 3400 6cly i dont know which one yesterday it said i was doing 50 but i was going slower and 30 when almost at a stop and the transmission shifts a little funny gtdad said it might be the speed sensor

You should have just followed up with that thread then instead of starting a new one.

Sometimes when its really cold your speed-o and trany can act funny.

But Your best bet is to get the car scanned with an ABS capable scanner.

How many miles on your GT ?

137000

Well I would say if the transmission fluid and filter hasnt ever been changed You may want to get it changed as GM recomends changing it about every 50K miles.

The speed sesnor on the trany is usually located on the tail of the trany.
I cant remember right off exactly where its located on the 4t45e.....

If you do think somethings wrong with the trany, get it to a reputable trans shop and get it scanned. This will tell them if anythings bad, sensors, pump, etc etc.

i changed the fluids a couple days ago when it started acting funny

i changed the fluids a couple days ago when it started acting funny

So changing the fluids, did it make it worse or still the same?

These transmisions are pretty weak and if they arent taken care of they will giv you fits.

I still say take it to a trans shop and get it scanned.
If somethings wrong with the speed sensor, they'll find the DTC's.