transmission

I have a 97 4x4 blazer LS auto transmission.
Ok about 3 months ago my truck was stuck in 3rd gear. I could shift manualy,but only get 2 and 3rd gear. Yes the dummy light came on.
But other days the transmission would be fine. So I went to Aamco
and on two differnt days thay did a road test and electricial test
as well. Thay said it was an electronic problem. I have a friend at a
dealership and he said he would help me out with cost and everything.

Now for 3 months The truck has been in and out of the shop for the
same problem. So far all the shif solenoids,Transmission motherboard,
and the frount pump in the trany have been replaced. Still stuck in 3rd
gear. So thay took my truck to a transmission shop and thay did tests
and said that the ignishen switch was causing the problem. It was
replaced.

When I got the truck back It shifted realy strong from 1st to 2nd and
the other gears shifted just fine. It did this only 2 times and was fine after that. That night I drove my truck to a friends house and on the way home 1st to 2nd gear would shift hard all the way home. Then the dummy light came on agan.

Okay now the truck will decide to be stuck in 3rd gear or shift through all of the gears but shift hard from 1st to 2nd


ANYONE have any ideas of what could be the problem????? any input is helpfull at this point.

i just use stock wires and plugs but youre idea sounds good

the hard shift from 1-2 is a common problem on the 4l60e transmission, the pwm(pulse width modulator)tcc(torque converter clutch) solenoid is probably causing your problem, my 99 did same thing, i think i paid 27.00 ordered it from ?? can't remember. the 27.00 was full price. pretty easy to put , drop pan, right there she is.. i have some info if you need it, but it is the pwm tcc solenoid.

O.K., so when your talking "transmission motherboard", by that do you mean the valve body? The valve bodies on the 4l60e's have a bad reputation for wearing out at certain points and can cause a whole variety of problems - like the 1-2 hard shift, no TCC lock-up, etc. There could be a few problems. When you took it to a transmission shop, did they check for codes pertaining to the transmission? Did they do a road test, check transmission supply line pressure at the transmission and at the PCM? Could be a bad sensor or solonoid, like a bad PWM like what 99church mentioned. A competetent tranny shop should be able to know if the PWM is giving bad or incorrect siganls to the PCM. Is your TCC locking up? When it engages, does it do it smootly or does it just do a bump type lock up. I had many problems with my transmission and have studied these transmissions in detail, so that why I have a little knowledge with this type of problem. Here is a company that perfroms miracles in finding solutions to some common problems. Not saying this is your problem, just giving you an idea as to some common problems with these transmissions. http://www.transmissionspecialty.com/parts/DM/4L60-E.htm

Ignition Switch!

1997 has a bad ignition switch in the steering column that will cause massive electrical problems and transmission issues.

Replace the switch and reset the computer and you will be good.

Slobby states that the ignition switch was replaced, and that did not solve the problem...

Ummm...

Where did he say that?

"Now for 3 months The truck has been in and out of the shop for the
same problem. So far all the shif solenoids,Transmission motherboard,
and the frount pump in the trany have been replaced. Still stuck in 3rd
gear. So thay took my truck to a transmission shop and thay did tests
and said that the ignishen switch was causing the problem. It was
replaced. "

Right at the end of the paragraph.

wow, that is crazy. I read it over 4 times.

Note to self, time for new glasses.

3 months in and out of the shop for the same problem? They may be playing you.. big time. Some things to check:
For the THIRD GEAR ONLY check for correct system voltage and/or a bad 3-2 control soleniod.
If the problem is 2'ND and 3'RD GEAR ONLY or 1'ST and 4'TH GEAR ONLY then this points to problems with the shift solenoids "A" and "B".
The slipping or rough 1-2 shift has five causes:
> Valve Body
>2-4 Servo Assembly
>2'nd Accumulator
>2-4 Band
>Oil Pump Assembly or Case
The most frequent cause is the valve body and the specific problems there are:
>1-2 shift valve train stuck.
>Gaskets or spacer plate incorrect, mispositioned, or damaged (worn at the check ball locations)
>1-2 Accumulator valve stuck.
>Face not flat. Valve body to case bolts are torqued at 8 lb. ft. in a specific spiral pattern. If they are tightened at random, you may distort the valve bores which will inhibit valve operation.
You mentioned the "dummy light" came on. What were the codes?

Do you have the codes from the dummy light?
If so please post