Need help troubleshooting P0758 Transmission Solenoid. Avy parked til solved...

So my tranny has never given me ANY probs til this past weekend. Wife and I were returning from a vacation in our 2002 Z71 Avy. Everything was running smoothly until we stopped for gas. After fill-up, my wife started the Avy and the Check Engine Light came on. From that point forward it only had one gear. It takes a while to get up speed (with little to no "slippage"), but at speeds of 45-60 it runs ok (around 3k rpm). So we had to drive it about 45 miles home like this.

I go to Auto Zone and they read code P0758, which indicates an electrical issue with my 2-3 tranny solenoid. I went ahead an purchased both solenoids, a new filter and a new gasket. Now, reading up online it is saying that it could actually be the ignition switch. Typically only if it throws MULTIPLE codes. Mine threw the same code twice... So should I go ahead and do the solenoid swap out first, or is there something much simpler I should check.

I have already reset the computer and both the issue and the SES light are still there on startup.

I have very basic knowledge of how to remove the trans pan and replace the solenoids, but I am afraid I wont be able to get the exhaust off to gain clearance. Any way around this? Or does anyone know if it is absolutely necessary.

Lastly, if the solenoid change doesn't work, where do I look next?

It's been a couple of years or so since I dropped an AV tranny pan but I believe you can do it without removing the y-pipe that runs under the tranny.

Besides what you've already purchased, you're going to need 5-6 quarts of tranny fluid, I can't remember exactly how much, maybe more like 8?

I read on the instructions for changing the solenoid that you should never change the fluid is it isn't burnt and has been in there an unknown amount of time. Reason being that the friction plates release a material that helps the tranny run properly after its been worn in, almost like a silt, and it is literally the glue holding it together. Before this happened, my tranny worked perfectly and I've never had a fluid change. Still ruby red.

You are probably thinking about the debate about flushing the fluid (schools out to that one) but I suggest you not reuse the old stuff. I would just refill it new fluid BTW you listed it as a 2001 in the first post is it a 2011.

2002. Sorry

Take a picture of where and how the shift cable is attached, they can be tricky to get back on in the right place.

Good luck.

MS03 2500 said:

Take a picture of where and how the shift cable is attached, they can be tricky to get back on in the right place.

Good luck.

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Yeah,  I've installed one "backwards".  To me "backwards" looks right so the picture advice is a good one.

Also I believe in agreement with MS03 2500 that you've probably read about a tranny flush vice a fluid change.  Unless you want to put the old stuff back in (I've done that before on a tranny rebuild that had to come back off but the stuff was literally brand new) I'd put new in.  You're only going to be replacing a little over half or so anyway as there's still going to be a lot sitting in the tranny and torque converter even without the pan.