Another automatic transmission question

I have a 1997 Chevy 1500 (owned it since new) with 213K miles, original transmission (should be a 4L60E), fluid is not low. This week the transmission has started to act erratic. In the mornings when the truck is cool, it has hit "neutral" when shifting to 3rd. Then when I let off the throttle it would go ahead and shift. After the truck warmed up and also after work on the way home, the transmission would shift normal. This morning it started out normal, but then after stopping, it acted like it was stuck in 3rd while in Drive, even when starting out from a stop. When this occurred, the service engine soon light came on. After work, the transmission was back to working normally.

Stopped at Auto Zone and had the codes pulled. It was showing a P0758 "shift solenoid valve or circuit." Is the shift solenoid valve the likely problem, or is it more likely some other problem? Also, on the 4L60E, is the shift solenoid valve external or internal.

Thanks for your help,
Tim

I dunno Jim,

It's been my experience that those solenoids usually fail mechanically more often than electricaly. Darned things get worn and won't operate "consistantly" every time and therefore running a test on 'em won't show what's really going on down in the trenches.

Sure could be your greif; trouble is they live inside.

Did the store clear all your codes for you while they were tied up to the system? Guess I'd force 'er set the code again before yankin' the pan.

Allan

Allan if you disconnect the battery for a minute will the computers reset the codes? I know it works for some stuff.

Naw,

They gotta be cleared on those OBDII systems.

Allan

No, they did not reset them...

The shift solenoids are inside the tranny. You'll have to pull the pan to change them. Did Autozone tell you which solenoid, because there will be at least 3 maybe four solenoids that control the shifting. If you pull the pan, look for large chunks, small stuff is normal wear. One more suggestion is do not have the tranny flushed because you will be rebuilding the tranny in a short period of time.

My 98 had the same trans, and same problem. According to what I was told by several shops and the dealer, theres a pump or something inside that was messed up at the factory, an oring inside would wear prematurely, and set that code off. Someone else can verify, but thats why the code reader didnt specify which solenoid. Cost me justas much to have a reman put in, than to have the one in the truck fixed, and it was done the same day, and had a 3 year warranty.

Mornin' John!

Those darned trouble codes are best viewed as a somewhat broad based "tool" and nothing more.

They don't tell you what the heck is actually wrong; they only help you to get into the right neighborhood to begin your analysis.

In Jim's case, the scanner retrieved a code P0758. So, this says that the computer has seen an electrical irregularity in the shift solenoid B circuitry. However, this means that the problem could be anywhere from the PCM/ECM clear down to the darned solenoid itself.

All it says is that the computer didn't see the solenoid snap for a period of 5 seconds from the time it was commanded. Very vague at best.

Now, (and you know what an azz I am about speaking my mind) any shop, service writer, or shop manager that wants to sell a fella an expensive complete transmission just to make this little problem go away, are actually saying, "We just don't have a clue about what is wrong". And frankly, they just flat don't know that they are talking about.

They WANT to sell that unit. It takes all the responsibility of a diagnosis/repair off of them and puts it right back on you and your pocketbook. Instant large amount of cash in their coffers without them actually doing anything.

You're right about that SRTA warranty tho. The shop wants it probably more than the owner. :>)

Like someone said earlier in the week, these are a fairly easy unit to repair, but Hey! How's about we take that $140 part and turn it into a $2K+ sale.........

Sorry fer the early morning rant; sure not directed at you.

But, I've seen this strong-arm tactic played out many, many times. Remember a fool of a shop manager one time trying to pull that same stunt over a plugged tranny filter. :>(

Allan