Tolbert

When I was looking around for information on symptoms of bad shift solenoids it was kinda hit and miss. I though I would start a thread about my symptoms and hopefully it might help others. Afterall, I saved myself the $3200 the shop wanted charge to replace instead of repair.

My symptoms were no overdrive or first gear on my A340H transmission. Slow take off and the engine was sitting about 4000RPM just to do 65. I checked all the connectors on the temp sensor and was unable to find any problems. When I shifted into 4 low and put it into 1st gear it worked great, so I knew mechanically nothing was wrong with the gears. But when back in 2 hi and a manual shift into 1st it would drive but it wasn't in first. I was able to go 40mph and when I shifted it into 2nd, no transition. So first was not working.

Through some online research, I was able to tell that one of the solenoids was not closing. I even found a you tube video for testing them.
After a junk yard trip for all 3 solenoids (2 shift and one for torque converter lockup), new gasket, and filter I set out to change them.

This job needs a large catch pan. It drops about 7 quarts of fluid and drips everywhere. All 3 solenoids can be accessed without removing the filter. Keep track of them and replace one at a time. One is different than the others, and it works differently. I was able to find my problem when I pulled the last one out and found the o-ring to be split. I also noticed that was not the factory orignal. It had been replaced before. After the solenoids, filter, and gasket where installed, new fluid was added. Truck warmed up and fluid level topped off, the test drive was awesome.

That little o-ring was the only problem. I tested all the old solenoids and they are all working.

Hopefully this helps anyone having the same issues. I have included a pic of the broken o-ring and shot of the valve body of the transmission. You can see the solenoids in the pic.

scope103

Do you have any recall which solenoid had the bad o-ring?

According to this page, no combination of failed solenoids would allow the transmission to stay in 2d gear.

Tolbert

I only had 2nd and 3rd. Shift solenoid 2 had the bad o-ring. I found a diagram to show each of the solenoids.

http://i22.photobucket.com/albums/b3...OLENOIDSID.jpg

According to your link, if solenoid #2 was always allowing fluid to pass only 2nd and 3rd will work since it cannot turn off the fluid with a broken seal.