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Discussion Starter #1
The car has an automatic trans. And about 107K miles and has been maintained religiously. The problem started while driving 70MPH on the highway. There was an abrupt pause in the forward motion, lasting about 1/10 of a second. The speed slowed only slightly and resumed (using cruise control). I kept driving as normal (60 mi. to work with 45 remaining) The transmission operated normally as far as upshift and downshift. After arriving at work, I found that I had no reverse, so I drove forward into a parking spot. I had a truck and car trailer delivered later to tow it home and found that I had no forward gears. The front wheels were also locked, in forward, reverse, and neutral while the car was running. After shutting the car off and letting it sit for 20 min. (pondering what to do...), I rocked the car and found that it rolled in neutral. Loaded it and towed home.
Codes PO700, PO715, and PO720 have been set. The fluid has been drained (long-time Amsoil user), all was crystal clear and absolutely NO debris or discoloration. I removed the final drive cover and all looks good as far as the differential operation, gears, and bearings.
I would think this would be a hard-part failure, but have more experience with non-elec. RWD transmissions. I am rather savvy and have my own shop with lift and normal equipment.
Any thoughts would be appreciated.
 

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Welcome to Allpar. Do you have a service manual? They show up on the web at times and a main public library may have one for loan. The factory service manual is best and the 41TE was similar between many years and models. ATRA and Sonnex also have 41TE diagnostic and repair guides. Follow the diagnostic procedures for 'No Drive or Reverse'.
You may need an ATF pressure gauge at the front pressure taps to measure clutch-apply pressures.
It does sound like an internal hard part failure by the description, but a diagnosis while it is in the car may help before it reaches the bench on where to look first.
It sounds as though the clutches are being applied and locking the transaxle when the engine is running and the front pump is pumping. After you shut off the engine, the clutches release and you are able to roll the car. You may find burnt clutches and blue plates if an internal leak has kept them applied when they should be off.
Disregard P0700, that is just the PCM saying that a code(s) are present in the TCM.
P0715 is an input speed sensor error. P0720 is an output speed sensor error. Possibly caused by clutch slippage. Electrically it would be rare for both to fail together. A scan tool diagnosis may go further with information than just the fault codes.
If you unplug these sensors, the transaxle will go into limp-in and you should should have P, N, reverse and 2nd gear. If it is still locked up, this confirms an internal hydraulic or mechanical issue and not an electrical issue. The transaxle will likely have to come out and apart.
Special tools needed are also shown in the service manual. You can possibly find or fabricate something that will work.
For all the hype about Amsol products, it is NOT recognized as an ATF+4 oil: http://centerforqa.com/licensedatf4brands.html
Only their marketing department can say 'recommended for' without actually meeting the important MS-9602 spec.
Any ATF that you do use in the future must meet Chrysler MS-9602 for best results: http://www.allpar.com/forums/topic/90635-atf4-vs-amsoil/





Here are ALL the oil suppliers listed on the current Engineering Approved Source List for Chrysler ATF+4 (MS-9602):
Shell Oil Co.
• Petro-Canada Products
• Texaco Europe
• The Valvoline Company
• Exxon-Mobil
 

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Discussion Starter #3
I do have a set of factor service manuals and have been reviewing them. I can see the logic of the causes you stated, but am having trouble wrapping my head around the sequence of events in the failure. The initial "shudder", which was followed immediately by the codes being set, while driving, continued operation for another 45 miles (at speed), and then complete lack of movement after the car was shut off.
I will review the "No Drive or Reverse" test procedures.
I am not an Amsoil fanatic, but have used their products in all sorts of vehicles and equipment and have NEVER had a fluid-related failure. Authorized compatibility aside, I believe politics is well-seeded in the lubrication industry.
Thanks for your input. I will put your knowledge and suggestions to good use.
 
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