Converter unlocking under VERY light acceleration
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From: Dyess AFB, TX
Converter unlocking under VERY light acceleration I'm pretty sure my converter isn't completely locking up. Whenever it locks, the rpms will drop, then raise, drop, raise, and so on until I let off the gas. It seems like it's trying to lock but can't under acceleration. And usually I feel a slight jolt when the converter locks but now I feel nothing. But when the converter does lock, the slightest of acceleration will unlock it. I can literally go up a 0.5% incline and the damn thing will unlock.
At first I thought it might be a tuning/ignition issue so I changed the plugs, cleaned the maf, and cleaned the O2's. Didn't help. I'm throwing no codes so I have no idea what the deal is. I noticed it happens worse or more often when the trans temp is hotter. I checked the fluid and it looks and smells new. My converter better not be going out because that would be the second Yank to go out in 6 months
At first I thought it might be a tuning/ignition issue so I changed the plugs, cleaned the maf, and cleaned the O2's. Didn't help. I'm throwing no codes so I have no idea what the deal is. I noticed it happens worse or more often when the trans temp is hotter. I checked the fluid and it looks and smells new. My converter better not be going out because that would be the second Yank to go out in 6 months
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From: Poway, Ca. where GOD and the sun always shines
You do not state what year your vehicle is, however if it is an 01 or 02 model, I would bet it is a shift point issue possibly coupled to a TM issue. A good dyno tune should eliminate your problems, it did mine.
JMHO
SteveC
JMHO
SteveC
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From: Dyess AFB, TX
Originally Posted by MyLS1Hauls
Is it unlocking, or slipping? I've seen a few Yanks slip when locked up under load.
And it's a 98 w/ a full dyno tune. Definitely not a TM issue.
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From: Dyess AFB, TX
Originally Posted by 2xLS1
Your sig says cammed. Have your misfire tables been edited? You don't have to get misfire codes for misfires to screw with T/C lockup.
Also, this only started happening a few weeks ago. I've had my cam and tuning for over a year. I don't see what could have happened recently to cause the tuning to screw up.
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From: Dyess AFB, TX
Originally Posted by MyLS1Hauls
Post a bigger sig of what exactly your car has. Specifically what Yank verter?
Built Tranny by a pretty reputable shop here in Dallas (4 months old)
Full boltons minus a pulley
TR224
LS1 Edit tuning
My buddy was having the same problem with his PT4200 until we adjusted the misfire detection section, even though we turned off the P0300 code. You need to determine if its actually unlocking, or slipping. Another friend of mine was actually having slipping problems with his Yank Truck Thruster converter until we installed a TransGo TCC modification valve, but it started from day 1 with the converter. Is the fluid level full?
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From: Dyess AFB, TX
Originally Posted by MyLS1Hauls
My buddy was having the same problem with his PT4200 until we adjusted the misfire detection section, even though we turned off the P0300 code. You need to determine if its actually unlocking, or slipping. Another friend of mine was actually having slipping problems with his Yank Truck Thruster converter until we installed a TransGo TCC modification valve, but it started from day 1 with the converter. Is the fluid level full?
-Happens more often when trans temp is higher
-Usually doesn't happen the 1st time the converter locks, usually 2nd or 3rd and on from there
-Has trouble locking (RPMs cycle up and down when locking)
-Lightest acceleration unlocks it (possible slippage)
-Converter doesn't give the little jolt when locking up, I can barely feel lockup now
One thing I forgot to mention was this first started happening on June 2nd, which was our 1st really hot day, but trans temp wasn't out of the ordinary (150-180). I don't know if this had anything to do with it.
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Another thing to consider: If you have a manual lock-up switch (which is an easy mod) then lock up the convertor at speed, say 45-50, and just give enough throttle to maintain your speed. If the RPMs jump to around 3000, then you've burned up your OD clutch pack. It happened to me. I locked the convertor solid, but the RPMs jumped when I tried to maintain highwy speed. I took it to Joel's on Joy, and he showed me the smoked clutches. It's perfect now.
FWIW, Joel said that the 4L60E is a very strong trans on the upshift, but that the drums drain fluid axially rather than radially, and on downshifting, the fluid has nowhere to go as RPMs rise. That's what kills these trannies. The number one warranty on the 4L60E is the V6 S-10s, because they require so many kickdowns to stay in their powerband. They die all the time, I'm told.
Hope this helps, and your PM is returned...
SC-
FWIW, Joel said that the 4L60E is a very strong trans on the upshift, but that the drums drain fluid axially rather than radially, and on downshifting, the fluid has nowhere to go as RPMs rise. That's what kills these trannies. The number one warranty on the 4L60E is the V6 S-10s, because they require so many kickdowns to stay in their powerband. They die all the time, I'm told.
Hope this helps, and your PM is returned...
SC-
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From: Dyess AFB, TX
Originally Posted by Ed Blown Vert
I had the same issue with my cam
The cam will cause misfire codes. Turning off the SES light won't help. You need to turn off misfire detection at idle and low rpms.
The cam will cause misfire codes. Turning off the SES light won't help. You need to turn off misfire detection at idle and low rpms.
SS00Blue, thanks for the help. I was planning on locking it up with a Tech II and seeing what it does.
