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Converter lock

Is anyone familiar with “converter lock” and I mean in the literal sense. My tranny locked up as if I have stepped on the brakes. It unlocked when I went to neutral then drove off OK in low. But going back to Drive it locked up again. Now its in the shop waiting for a new tranny per the mechanic’s diagnosis of dead tranny. Sounds like a fixable problem without replacement.

All the a torque converter lockup does is “lock” the transmission and engine together so that they spin at the same speed. The main purpose is to increase fuel economy since when the torque converter clutch (TCC) is not locked up some of the engine’s energy is not making it to the wheels. This is a pretty short but informative description: - though there are tons and tons on good sites for explaining how auto transmissions work.

So whatever is going on in your case is not from TCC lockup. Whatever it is it might be a fixable problem (few problems aren’t fixable), but that doesn’t mean that it might not require removal & disassembly of the transmission.

Your best bet is a good, reputable, local and independent transmission shop - so hopefully the tranny mechanic isn’t from AAMCO or Cottman’s etc.

Do you mean when you come to a stop the engine stalls like it would in a stick-shift car if you did not release the clutch?? That is indeed a failed TCC. The torque converter normally unlocks as the vehicles speed drops below 20 mph…

Thanks for the reply. I read a little about the converter lockup and thought that might have caused the tranny to lock up the FWD and bring the car to a stop. Nobody I’ve talked with has heard of that happening. Being in a small town about 50 miles from the nearest medium size city (50k population) I don’t know of a reputable shop to take it to. I would be at the mercy of anyone who might not be good or reputable, plus the tow charge to wherever. Now looking for a compatible tranny that a local mechanic said he could put in. Appears that Chrysler put the H604 in several cars through years. Surely a salvage yard could cross index that and sell me the right one???

I’ve not really heard of a tranny locking up either. You said it locks up as if you put the brakes on. How do you know it is the transmission doing the locking up? Describe better what is happening. You put it in L and press the gas and the car moves normally. You move the shifter to D, press the gas and …?

This happened about 3 or 4 times in the space of 2 city blocks - in D. When I stayed in L I made it the 6 blocks slowly to a garage. Then made it to a car lot with the intent to have his roll-back take it home - 4 more blocks in L. Never tried D again. Thinking I would have to have it towed SOMEwhere to be fixed, I left it there. Could I be the first to experience such a paranormal phenomena?

“This happened”

You still haven’t said what “this” is. What - exactly - happens? You say “my tranny locked up” - but that doesn’t say anything. Exactly what does the car do?

OK - let’s try this. I’m driving along @ 30 mph and you’re in the passenger seat. All of a sudden you’re bracing yourself with your hands against the dash to keep from going thru the windshield. The car comes to a complete sudden stop. You say “why did you slam on the brakes?” I’m holding on to the steering wheel to keep from going thru the windshield also.
Car behind honks the horn and I to wave him around. Now I go to N with motor still running, then back to D and go again. Repeat scenario 3 times. Then I try L and limp to a local garage with no problem, other than slow speed in L. Mechanic tells me this happens when the tranny is shot - ya got L and R for a while, then yer done. Does this give you a better picture? I appreciate your interest. Ask me more~~~~~~~~~

Does the transmission lock when it does the 1-2 shift or the 2-3 shift? I referenced the diagnostic trouble table for the 41TE four speed transmission which your V6 should have. That table indicates that a clogged filter, a high fluid level, or aerated fluid would cause this problem. I would have expected something along the lines of defective solenoid pack or TCM problem where the clutch solenoid for 1st/rev clutch is not releasing that clutch while 2nd/4th clutch is engaging. So get back to us on which gear ratio (other than drive) is causing the lock.

I trust you have checked the fluid level, smell, and color. BTW, is the check engine light ‘on’ or the OD light constantly lite or flashing? Take the car to a qualified transmission specialist and have him/her scan the TCM for codes, freeze frame data, and clutch volumes. It would be nice to see the data as the transmission locks.

Keep us appraised of the progress on this problem.

It seems to be at the 2-3 shift but I don’t recall a shift when it locked. It didn’t lock at all for about a half mile of slow driving in the L position. I did check the fluid level and it was over the top line on the stick. I thought about trying to siphon off some fluid and see if that helped. The tranny was slipping the day before and that’s been a sign of low fluid for the past couple of years. I’ve had to add a quart about once a month and slippage indicated low fluid so I added a quart. I told the mechanic I first took the car to and he said it didn’t matter - it has a bleed off tube that dumps any excess fluid on the ground. I was dubious. In any event, with 180k on it I went ahead and bought a 130k 96 Stratus 41TE for $400 + $250 for R&R. I am told that the '96 is the only 41TE that will fit my car, so rather than having it hauled to a trans shop and have them tear into it at an estimated $1400 I opted for a lower mileage tranny, guaranteed for 30 days which shouldn’t leak on my garage floor. Tranny and car delivered to the shop for $75. Before he pulls it I think I’ll have the guy pull down some fluid and take it for a drive. If that solves the problem then I’ll have a spare in case the “new” one fails down the road. Wish it were easy to get it to your shop for diagnostics and maybe save a few bucks. Thanks for your time and advice. I’ll advise if the pulling down fluid solved it.
Mike at Dunmore, KY.