the past couple days i've noticed that my blazer's transmission is slipping. if i don't drive it like a granny i can feel it slipping while accelerating, and it will rev too high (3-4k RPM) then slam into the next gear. using cruise on the highway where it used to hold speed without kicking down, it'll kick down a gear or two and still lose speed.

the transmission fluid color looks fine and smells like crayons (not really sure what it's supposed to smell like). i can't tell how full it is because the fluid is all over the dipstick when i check it (in park, engine running, engine and trans up to operating temperature).

it seems this started happening out of nowhere, but i've always gotten a feeling that the transmission was a little funky (takes a few seconds to go into gear, etc.). the alternator was replaced a few days ago. could this be nothing more than an electrical problem? can i reset and force a relearn? (i've read that the 4L60E is an adaptive transmission)

 

is there anything i can add to this thread that would help diagnosis?

 

I dunno, try adding 1/2 a litre of fluid and re-checking the level and the shifting/engagement.
If that doesn/t help, get a free road test from a tranny shop.
When is the last time you had a fluid and filter change?

 

just a side note, the fluid always seemed full when i checked it before.

there aren't really any dedicated transmission shops in town.

i don't know when the fluid and filter were last changed. i bought the truck last february.

 

I would get at minimum fluid and filter changed to see if this helps then ask the tranny shop why the dipstick is so hard to read. It may indicate a problem with an internal part that is allowing to much fluid resting in the pan and not flowing properly (only educated guess). Might be the filter is clogged with debris...

 

haven't had a chance to take it anywhere to have it looked at yet. i did however check the codes and it's throwing P0101 (Mass Air Flow (MAF) Circuit Range/Performance Problem), which it wasn't doing before this started happening. could this be at least part of the problem?

 

The MAF sensor plays a role in a TON of systems on the newer trucks, including shift functions.

Before replacing it, try cleaning it to see if that helps. To clean, remove and disassemble the sensor (remove the 4 bolts holding the aluminum halves on). Using some sensor safe carbon cleaner, spray the exposed metal pieces of the sensor paying special attention to the resistor elements. These elements are VERY fragile so be careful. The elements should clean up to a whitish silver color. If you cannot get them clean enough with the spray alone, you may have to very carefully clean the elements with a q-tip soaked in the carbon cleaner. Once clean, allow to dry, then reassemble and reinstall.

 

thanks for the information where is the MAF sensor located on a '97 4.3? (not sure where my FSM set is right now) would've noticed this earlier if the SES light actually worked.

 

The MAF sensor is in the intake ductwork between the filter box and the throttle body.

 

before:
http://magtec.rvglug.org/misc/blazer/97/MAFbefore.jpg

after being liberally doused with air-intake cleaner and swabbed with a q-tip:
http://magtec.rvglug.org/misc/blazer/97/MAFafter.jpg

cleaned up the housing a little bit too while i was at it. just waiting for it to dry so it can be reinstalled.