# 03 Trailblazer shift solenoid b



## abg (Aug 23, 2008)

I have check engine light. Code reads shift solenoid b stuck on. Do I have to remove the pan to change it and where exactly is it?


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## SABL (Jul 4, 2008)

Hi abg,

At this time all I can do is guess. Most solenoids are located inside of the tranny and bolted to the valve body. ATSG publishes service manuals for automatic trannies but are not readily available in normal auto parts stores..... you can find them at transmission parts suppliers. Maybe your local library would have what you need in the reference section. 

Automatic transmissions are nothing to tinker with..... you have to have a keen eye and pay close attention to detail. The solenoid is an easy task once you identify which one is at fault..... anything more is going to be technical in nature. 

If you cannot find any real info I will ask my son to check his manual and lend some advice. He had to purchase the manual when his "sun gear housing" failed.... no fun!!

Best of luck
SABL


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## abg (Aug 23, 2008)

I looked in the Haynes manual at the auto parts store with no luck. They don't show much on trannies. Any help would be appreciated.


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## SABL (Jul 4, 2008)

You won't find anything in Haynes or Chilton on trannies. The only source I know of is ATSG.... Automatic Transmission Service Group.

I'll call my son to see what model tranny is in the Trailblazers if I can't get the info from the net.

What symptoms are present other than the code being thrown??


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## abg (Aug 23, 2008)

It shifts into 2nd ok but not into 3rd. Sometimes the engine races and then it jumps into 3rd and sometimes it doesn't shift at all. I looked at the fluid and it is real thin and light brown in color. Smells bad. I need to change it and the filter, but I want to change the solenoid at the same time since I need to pull the pan for both. Also is there a way to drain the converter without disassembly?


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## SABL (Jul 4, 2008)

ATF (Automatic Tranny Fluid) is rather thin compared to some of the other fluids in your car but should not be like water. What I don't like is the ATF being brownish and having an odor...... does it smell burnt?? That indicates wear on the "frictions"..... the thin plates with a clutch material on both sides. 

Let me do some checking and I get back


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## abg (Aug 23, 2008)

It may not smell burned but it does not smell like transmissionm fluid.


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## SABL (Jul 4, 2008)

No luck so far on the net...... I could have been to my son's and back by now. 

Check the wiring diagrams in the back of your Haynes manual.... it does show the solenoids and the color code for each solenoid. 

I'll be back


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## abg (Aug 23, 2008)

I took the pan off. Kind of messy with no drain plug. I found the solenoid with no problem. When I removed them, one of them had pressure in the valve body. The other one didn't and the valve was hard to move. I changed the filter and cleaned the mess from the pan and reinstalled. It ran the same. I called Chevrolet and complained about all the problems I have had with this vehicle and the tranny be bad after 52,000 miles. They told me to take it to a dealer for evaluation and they might help with the bill. That's where it is now.


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## SABL (Jul 4, 2008)

Not good..... how much mess in the pan?? There should be a magnet in the pan to trap any shavings which are normal. A large mess is trouble..... and with the ATF being off-color could mean failed frictions. Hopefully GM will foot much of the bill for this problem as there are concerns with this tranny. In the late 70's/early 80's GM had a major problem with the trannies in the 4WD suburbans that they could not keep up with production to satisfy the need. It just happens.... automatic trannies are very complicated and the average mechanic should avoid them at all costs and leave them to a specialist.


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