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TCI 2,400 stall speed Torque Converter

tarafied1

Well-Known Member
Well back in December I posted that I bought a TCI 2400 stall TC. I put it in a few weeks ago. I have been preparing for the 2016 HRPT. If you have followed my saga, last year on the PT the tranny (now named Caitlyn) was overheating at speeds above 60mph. I limped the car along the tour to the end but decided to rent a U-Haul truck and tow dolly to bring it home rather than try to drive ~700 miles below 60. Anyway, once home I still drove it a lot. The diagnosis was that the sprag must be locked up in the TC since everything else seemed to be working okay. So rather than put a junkyard stocker in there and since I still don't have $6K to convert to a TKO, I went with the TCI.
Well it's in! It drives like a car with a higher stall speed. But it's not too bad. I kinda like it. Two weekends ago I took it on about a 60 mile round trip that included about 20 miles on the interstate at 80+ mph, some city stop and go and some casual 60-ish country road driving. The tranny never got over 195. Granted the weather was in the 60's and not 90-100 like on the tour but I am reasonably comfortable it is fixed.
BUT, just to be sure, I decided to cut open the old TC. And guess what? It was the sprag. Pics below. The little springs in several rollers had failed and were jamming the rollers. Also the turbine and housing thrust washer was a bit gnarly looking.
IMG_3483.jpg Torque Converter cut open.jpg Torque Converter sprag failure.jpg Torque Converter turbine trust washer.jpg
 
Cool, looks like you found the culprit. Is that a floor jack you're rolling the tranny around on or what?
 
Well,
The TQ was shot but that was not the only problem. Tried driving to Hotlanta yesterday. The trans still gets hot above 60 mph for extended periods. I got from home to South of Nashville before she really got hot. Stayed about 190 until I got on the interstate. I was driving 75 mph. It rose to 210 and I pulled off to let it cool. I decided to take it back home. It quickly rose to over 230 on the interstate but I was mad so I kept driving it. Got back on the two lane North of Nashville and temp slowly dropped. It kind of went up and down around 210-ish all the way home. Never slipped or had any noticeable issue driving, just hot. I parked it and got in my Fusion and drove back down. Looks like Power Tour is a bust this year. With my travel schedule, I don't think I will have time to sort it out and I don't trust it to drive 3,000 miles in deep South heat! very bummed out
 
What about picking up another used auto and slapping it in for now? Or maybe just taking yours to a shop and let them figure it out. Either way would be considerably less $. Hate to see you miss the Tour knowing how much you enjoy it. You surely can find a day to reinstall a trans.
 
I made a summary of a Summit Racing video about Torque converters:

Torque Converters- Video by Summit Racing

Rules of Thumb:
1. Select a converter that stalls 500 RPM higher than the starting RPM of the camshaft- where the cam starts to make power (most important rule)
2. Converters installed in a big block engine usually stall 300 RPM higher than small blocks.
3. Choose a converter that will stall below the highway cruise RPM- must know gear ratio and tire size. A higher number gear ratio stalls sooner. A smaller tire has a lower stall.

Stall too Low:
1. Engine shuts off when trans put into gear
2. Poor acceleration
3. Car lunges and tries to override the brakes

Stall too High:
1. Small operating range for engine and trans
2. The converter never reaches the stall at cruise RPM
3. The trans over heats or burns fluid due to converter never stalling. Normal trans operating range is 170-210 degrees F.
 
I made a summary of a Summit Racing video about Torque converters:

Torque Converters- Video by Summit Racing

Rules of Thumb:
1. Select a converter that stalls 500 RPM higher than the starting RPM of the camshaft- where the cam starts to make power (most important rule)
2. Converters installed in a big block engine usually stall 300 RPM higher than small blocks.
3. Choose a converter that will stall below the highway cruise RPM- must know gear ratio and tire size. A higher number gear ratio stalls sooner. A smaller tire has a lower stall.

Stall too Low:
1. Engine shuts off when trans put into gear
2. Poor acceleration
3. Car lunges and tries to override the brakes

Stall too High:
1. Small operating range for engine and trans
2. The converter never reaches the stall at cruise RPM
3. The trans over heats or burns fluid due to converter never stalling. Normal trans operating range is 170-210 degrees F.
How ironic! I just watched that same video the other night and thought about it when Craig posted his last description of problems! An auto trans mechanic I am not!!
 
I did the math, and I think stall speed is right where I need it. At 70 with my tire size and rear gear, the rpms should be 2980. I had the GPS with me and speedo is accurate. Tach was just re-calibrated. I am reading 3000 rpms at 70 (it's a 8K tach so pretty hard to see a difference of 20 rpms). Pretty sure no slipping. The fact that it runs cooler at slower speeds also suggests it's not the TC slipping. Also it pulls hard even when hot. No apparent issues when driving. If the gauge wasn't there I wouldn't suspect anything was wrong like before when the TC was going bad. It got so hot it pushed fluid out of the vent and it melted the the speedo cable housing and it twisted off and broke. I know it was hot then. I have replaced the cooler, the TC and of course all the fluid.
I checked the flow rate to make sure the pump wasn't failing. I found a document on the web from an instructor for training technicians for Ford dealers and it says 1/2 quart in 30 seconds is good. I checked it twice today and I am right there. Fluid is red, clean and doesn't smell burnt.
I thought about a used tranny swap but C6's are hard to find and you never know what you are getting. That would just be another thing for me to worry about, a potential failure in the heat of the trip. I am so disgusted with this thing. All the stress from the last half of last year's trip and the added expense of towing it home with a U-Haul has left me feeling pretty un-enthused about driving 3000 miles worrying about it all week.
On another note, I am not entirely sure the gauge isn't messing with me. I ordered some temperature indicating stickers. I am going to stick on the pan. They change color if the temp is reached. They range from 170 up to 240.
As for transmission shops, I do not have any faith a trans shop would be able to fix it or even figure it out. Most are just rip-off artists who swap out the trans. When the low/reverse clutch broke I shopped around for a trans shop and many didn't even know what a C6 was so I did it myself.
Thanks for the support though, I am really really bummed we will miss this year. My son's are bummed too. Both had secured vacation time and Lucas has been getting the 99 all ready by changing the oil and plugs and stuff like that. My dad offered his 66, my wife said we could take the 07 and so forth but I decided just to save the expense and put it toward the car.
 
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