2006 4L60E starts out in 3rd

This ONLY happens when I back up first then switch to Drive (like backing out of the driveway then driving off).

I can manually shift between 2nd and 3rd but never goes into 1st nor Drive.

If I pull into the driveway then turn the truck around to face the street and later drive straight out to the street (not reversing) it's perfectly fine.

Never any slippage or any other problems and it's started suddenly three days ago...

Please tell me dropping the pan and replacing a solenoid or two is the answer...

I had a CEL for EVAP already so I don't know if another CEL for the transmission popped up. I'll get the codes but as far as I know, LIMP MODE is 3rd gear and Reverse but it's not permanent as mentioned above, it happens only when I back up as the first input to the transmission 

Take this with a pile of rock salt but that sounds like a gummed up valve body.

In reply to pres589 (djronnebaum) :

Thank you! Hopefully it's not gonna end up a complete rebuild.

Agreed.  Valve body or solenoids.  Also check the internal wiring harness.  The constant heat and hydrocarbon atmosphere tends to eat them.  They will look just fine, but they get microfissures in the jackets and the oil seeps into the conductors causing resistance.  The trans temp sensor is also inline somewhere in that harness.  I don't think the temp sensor is your problem, but it often fails as well.

4L60/65E was known for the bores of the piston valves in the valve body becoming galled and sticking.  Another known issue is the separator plate/gasket between the valve body and the trans becomes defective.  The check balls peen agains the holes in the plate and wear them out to the point where the check ball gets stuck (or falls through completely)

In reply to Curtis :

(by the way, did it last night, this morning but NOT lasted this morning so it's intermittent)

All still fixable with transmission in the truck (I hope)?

I have a great mechanic, I'm trying to get an idea of the cost of the fix before I even bring it over.

$250 for a replacement valvebody with at least some parts from Sonnax?  https://www.amazon.com/Shift-Rite-Transmissions-replacement-Valvebody/dp/B00STN8L06

It should all be do-able in the truck.  The wiring harness (if you need one) is a bit tough to get out of the case, but doable I think.

Valve body is just a pan drop.

There are plenty of reman valve bodies out there as well for not much money.  I would often do low-mileage used units for $60-100.  There are sources out there that pull them from known used units and stuff them in a bag to send to you.  If it were a Jatco or a VW 01A I'd be skeptical,  but 4L60Es are pretty simple and robust.

ebonyandivory said:

 

I have a great mechanic, I'm trying to get an idea of the cost of the fix before I even bring it over.

 

Keep in mind that even the best mechanics tend to cover their butts with transmission work.  It's not quite like ignition work where you can test everything and fix the issue.  It's more like a P0300 code which could be caused by a few hundred things.

I say that because he may still recommend a rebuild to cover his butt.  Too many times at the shop we fixed the simple problem (for instance, a 1-2 servo in a 700r4, or an accumulator spring in a 4r100w) only to have the customer come back because there was other damage because of the simple failure.  That happened a lot with RE05r Nissans.  They would come in with a busted trans mount, so we would put in a new mount only to realize later that there was an intermittent solenoid failure making it rip the trans mount.  Suddenly, we were a terrible shop who couldn't fix the problem, we had lost all credibility, and we were telling the customer that their $300 mount repair will now cost $3500 for a rebuild.

Just know that (although a valve body might solve your issue), it's hard to tell if driving it in just 3rd caused the direct clutches to overheat.  If he suggests a rebuild, just know he might not be trying to just line his pockets.  Also know that if he agrees to just fix the simple problem, don't get ticked if there is more damage inside.  Given the voodoo complexity of the hydraulics, mechanics, and electronics in there, it is often very difficult to diagnose anything to its full extent.

In reply to Curtis :

I will certainly heed your advice! Thank you!