Help: 2004 V8 transmission oil change

[Greydog]

Good news !

 

[WXman]

Once you get to Check temperature ange, you can remove the SST/jumper wire. Just leave the engine running and pull the small check plug in the transmission pan to let the overflow drain to a trickle.

That's not what I was told. I was told that jumping the wires (or using the proper diagnostic tool) causes the pump to run differently and you want that going to properly check the fluid level.

I think there are so many theories and stories on how to do this that it's caused a lot of confusion.

The revised temps start at 97 degrees. Which means in the summer when I did mine, I didn't have to warm up the fluid at all. It was already in the 90s ambient and the fluid would have gotten to full temp within seconds of starting the vehicle. The only reason I went ahead and jumped the wires was to get the pump going like I had read on this forum.

Can anybody confirm this?

 

[JB.]

I'm not sure when I pulled the wire while doing the official temp check, but I'd guess it was afterwards. In any event, that procedure and the shortcut procedure matched each other and using them produced a level that matched the factory fill.

 

[DC runner]

This is why I let the dealer do it. I do 95% of my own work, but you start messing with something like this: I got lazy. Besides, when a dealer does it.. you get a warranty. If the trans dies within 12 months of the change and you can reasonably argue oil; it is covered.

 

[BlackWorksInc]

That's not what I was told. I was told that jumping the wires (or using the proper diagnostic tool) causes the pump to run differently and you want that going to properly check the fluid level.

I think there are so many theories and stories on how to do this that it's caused a lot of confusion.

The revised temps start at 97 degrees. Which means in the summer when I did mine, I didn't have to warm up the fluid at all. It was already in the 90s ambient and the fluid would have gotten to full temp within seconds of starting the vehicle. The only reason I went ahead and jumped the wires was to get the pump going like I had read on this forum.

Can anybody confirm this?

The transmission fluid pump is mechanically run by the torque converter and by extension the engine RPM. There's a valve I believe to regulate pressure to an extent; but it is not affected by "diagnostic mode" when checking transmission temperature.

 

[WXman]

The transmission fluid pump is mechanically run by the torque converter and by extension the engine RPM. There's a valve I believe to regulate pressure to an extent; but it is not affected by "diagnostic mode" when checking transmission temperature.

Ok great. So if doing this on a hot summer day, there is no reason to fool with jumping the wires at all. Just start the engine, cycle through all gears slowly, then leave it running and pull the check plug. :thumb:

 

[JB.]

No reason to pass up the chance to feel the bottom of the pan when pulling the overflow plug, after letting idle speed get to normal.