Transmission shudder

A couple months ago the transmission in my 1999 Grand Caravan ES quit pulling. It is a 4-speed automatic coupled to the 3.8L V6. I had the filter changed and it began pulling again, but the fluid used in the filter change was Dexron III. It shuddered when the torque converter would lock after that, so I had the transmission flushed and replaced the fluid with ATF+4. That solved the problem for a short while, but now it shudders much less often, but quite noticeably when at highway speeds. My Check Engine light has come on, showing DTC's 0700 (Transmission Control System Malfunction) and 0740 (Torque Converter Clutch Circuit Malfunction). I cleared the codes but, of course, they have come back. I don't mind resetting the light occassionally, but I fear that I'm incurring further and permanent damage to the transmission if I don't solve the root problem. The problem is, I don't know whether I need to have the torque converter replaced, replace the Trasmission Control Module, or if the transmission needs rebuilt. I don't want to depend on the local transmissions shops to make the correct diagnosis the first time. Any ideas? Thanks.

A couple months ago the transmission in my 1999 Grand Caravan ES quit pulling. It is a 4-speed automatic coupled to the 3.8L V6. I had the filter changed and it began pulling again, but the fluid used in the filter change was Dexron III. It shuddered when the torque converter would lock after that, so I had the transmission flushed and replaced the fluid with ATF+4. That solved the problem for a short while, but now it shudders much less often, but quite noticeably when at highway speeds. My Check Engine light has come on, showing DTC's 0700 (Transmission Control System Malfunction) and 0740 (Torque Converter Clutch Circuit Malfunction). I cleared the codes but, of course, they have come back. I don't mind resetting the light occassionally, but I fear that I'm incurring further and permanent damage to the transmission if I don't solve the root problem. The problem is, I don't know whether I need to have the torque converter replaced, replace the Trasmission Control Module, or if the transmission needs rebuilt. I don't want to depend on the local transmissions shops to make the correct diagnosis the first time. Any ideas? Thanks.

You should probably change the fluid again. And make sure you are using the correct type for the year. I've had to change the fluid 2.3 times after someone used the wrong stuff......


Good luck, Gary.

Yes I agree with turboduck You didnt mention if you drained it or someone else but you can't get all the oil out of the torque converter when draining the pan. Old trannys had drain plugs in the torque convertor but they don't anymore. So what Dextron was left in the convertor is mixed with the ATF+4 you added. So draining a few more time is needed. I know the stuff is expensive. I have used Amoco ATF+$ from autozone and had no problems.

ANdy

Sorry you did mention you had it flushed. this would have got most of it I think, but still drain some more. I havea way to 4.5 qts out of it with out removing the pan. Take a 5 foot long piece of clear plastic 3/8" tubing. After the trans is warm stick it down the dip stick tube as far as it will go. But not too far so it starts to curly upwards. PUll a vacuum on it with your mouth, this is why youu have a clear tube, lol
Do this with the suction endnear the ground and place it in a pan when the oil gets near the end. it will take a while since the tube is small but you can normally get over 4 qts out this way.

andy

I also had the same codes 700 and 740, few weeks later, my transmissin died on the highway. 2001 Town and Country. After a rebuilt tranny, they said that the cause was from overheating, and installed an aux trans cooler, in place of the tranny fluid going thru the radiator.
Hope this helps, and you don't get stuck like I did. It's no FUN!

Did you have your transmission "flush" before seeing these codes?
I am planing to do a flush but heard so many negative opinion on it...

No I didn't, wish I would off, but, I don't know if it would have made a difference. Good Luck.