ughhh 4l80e problem!!! EXPERTS?

[RED MONSTER 4X4]

Alright, today i drove to a client's place for a pick up, the truck was fine, i turned the truck back on, and it was not shifting properly. Long story short, it WILL NOT go in to 4th(od) and to get it to shift in to 2nd or 3rd it takes quite a bit of RPMs. Any ideas? could it be something simple like a solenoid? or are we talking a rebuild already? I have honestly only put 2k on the truck since i bought it. and was told it was very recently rebuilt.

Few other notes, when putting it in drive or reverse it has always engaged VERY rough! big *kerthunk!*
trans fluid is full, but i do know the transfer case has a slow leak which i just filled to the brim.

any help would be appreciated guys!

Pretty freaking bummed out.

 

[Cruz89K5]

Does it go into first or start in second? I know the 4l60e will stay in 2nd and 3rd without electronics.

 

[76zimmer]

perhaps its in Tow/Haul mode without the light coming on?
Might need to pull a code to find out something. My 99 had codes, but wouldn't show on the "service engine" light.

 

[RED MONSTER 4X4]

As far as I can tell, it starts in first,like normal, but getting to 2nd and 3rd takes a bit more effort and Rpms than normal. I have not put the truck in 2nd and tried starting it, should i? and i did not risk trying to make it go in to 4th by over revving the engine. I just got off the phone with my Mechanic and he says quite possibly could be a shift solenoid 1-2 or 2-3 either way I would just replace both. Crossing my fingers this is the case.

 

[RED MONSTER 4X4]

perhaps its in Tow/Haul mode without the light coming on?
Might need to pull a code to find out something. My 99 had codes, but wouldn't show on the "service engine" light.

i would not even know how it put it in tow-haul mode. this truck does not have that option.Would the engine do this on its own? I will say when I started it and backed out of the driveway, i did forget to un-latch the parking brake, but before i drove of remembered to pop it. no more than 60 feet from driveway to my street. not sure if that could have done anything....doubtfull.

 

[Greg Ducato]

I would scan this and check the throttle position sensor to make sure it is in range. Shift solenoid failure will not induce the problem you are having. Also have a look at the output speed sensor signal.

 

[RED MONSTER 4X4]

I would scan this and check the throttle position sensor to make sure it is in range. Shift solenoid failure will not induce the problem you are having. Also have a look at the output speed sensor signal.

Thanks Greg, why would it all of a sudden just happen? I have no CES light going off, I am thinking to pull the battery and reset the ECM and other sensors? or would this be totally pointless? the truck ran just fine yesterday. It had been sitting for 4 days prior however.

 

[Greg Ducato]

If it is electrical, and it probably is, then think of how many times you have turned on a light switch and the bulb had burned out. The 4L80E is a very strong and generally reliable unit but is entirely dependent on the ECM to control it, and in turn it's many sensors to relay the proper information to the ECM.

 

[RED MONSTER 4X4]

Well i took it down to Autozone to see if they could check any codes, and wouldn't you know, they can't do that in California anymore, because the Dealerships claim "bad business practices" what horse crap! Anyhow the Darn truck ran like a top! No issue what-so ever!!! shifted as normal! guy at autozone said the "speed sensor" may be going wonky. makes sense i guess, i will have to investigate further. as of now, no issues to be had! lets hope i dodged a bullet on this one!

 

[Greg Ducato]

Have a peek at the wiring going to the sensors, it has been known to loose the insulation and come in contact with the case or the other wire. Also, check to be sure the small ground wire from the battery to the body is in place and connected well.

 

[warrpath4x4]

o'reilly should be able to check the codes also. i know with o'reilly its regional wether or not they will check the codes.