Shifting blues...

[farmboi]

Good afternoon:

I have a 92 Chevy 1500 2wd 350tbi auto. I drove to work yesterday morning with no problems what soo ever, nothing out of the ordinary during the drive. The truck sat for about 12 hours at work before i started my trip home.

As soon as I put the truck into OD I felt a very hard jerk, as if it was a stick and i just started the car in while it was in gear. The truck took off fine, but would not shift into second, just rev'd higher and higher. I punched the gas and it shifted very, very hard. Then it did the same thing when it should've shifted into 3rd. It drives fine, once I get it to shift, which requires me to "gun it."

I am in no way knowledgable in transmissions, but this to me doesnt sound like a mechanical problem. But again, I am clueless in these things. Thank you for your help in advance.

[jdmccright]

First thing I'd check is the transmission fluid. See if it needs more. If it is way low, you might consider just draining and refilling it since the remaining fluid has probably been cooked. Look at the fluid on the dipstick, too. If it isn't red or has a burned smell, it definitely needs changing. If you have changed it regularly, I'd suggest a tranny flush to get all that bad fluid out. But if you've neglected it (which many people do)...I would go for a regular drain & fill, replace the filter. Then drive for about 500 miles and change it again. This will replace most of the fluid in the system while reducing the chance that some buildup could come loose and block a vital passage or become lodged in a valve, resulting in complete tranny failure. Tranny flushes after owner neglect has been known to cause this type of failure.

If it continues after the check/change, I had a similar problem on my '96 Jimmy where it felt very sluggish and would start out in 2nd gear and stayed there no matter how fast I tried to go. This happened on my way home from Disneyland, Friday afternoon, 4pm closing time in small towns. Turned out to be a bad shift solenoid. But you have a 700R4/4L60 versus my 4L60E, so I can't say you even have solenoid controls (anyone else know?), and your truck is pre-OBD, so I'm guessing you or the mech will have to pull the pan to see what's up. Hope this helps!

[update]
The 700R4 doesn't have solenoids, only valves...a valve body rebuild may be in order.

[farmboi]

Anyone know what these two items are? Could either be causing my problem?

http://i119.photobucket.com/albums/o...2/P1030794.jpg

http://i119.photobucket.com/albums/o...2/P1030795.jpg

[2000CAYukon]

The first one is the vehicle speed sensor.

The second picture, it could either be the pan gasket (most likely) or the shift shaft oil seal.

The pan gasket looks to be leaking quite a bit and should be replaced (since you have to drop the pan, replace the filter).

I am not sure if the VSS has a gasket or O-ring that can be replaced. Maybe someone else can let us know.

EDIT: Looking at a picture of the speed sensor (http://198.208.187.182/internet/View...Number=213-194) there looks to be an O-ring that you might be able to match up at a part store to replace it.

//2000CAYukon

[jdmccright]

If your tranny was low on fluid and that's the reason for the malfuncton, then these two (or three) leak sources could be it. But it would have had to have been leaking for a long time between checks. I do not see any leakage coming from the output shaft seal. Also, check all the transmission fluid hoses and conections to the radiator for leaks at the metal crimps...leaks here are common, too.

[HUNTERPAUL]

Sounds to me that you have a stuck detent valve or a govenor.When the problem is in every shift these components can effect all shifts. If the detent valve is stuck a very harsh slam on the throdle pedal "with engine off" for 5 to ten times can unstick the valve. I the govenor is stuck removal and cleaning is required "not hard to do"