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I have a 1993 Suburban, 1/2 ton 4WD with the 4L60E transmission. In 4th gear, overdrive, under load the transmission will shudder. If you press the brake pedal lightly or shift out of overdrive the shudder will quit. Other than that the transmission works fine, I don't notice any slipping. Fluid and filter was changed about 15K miles ago. I have heard that it could be either the TCC solenoid, TPS solenoid, a worn valve body, or even the torque convertor itself. Has anyone have experience with this or any thoughts or ideas? I just don't want to replace parts that I don't have to. Thanks for any advice!!
 

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i dont think its tour torque converter, i would suggest taking it to get looked at as soon as possible. My tranny did the same thing because i forgot to take it out of over drive when i was hauling my lawn trailer and i lost 2nd and 4th. It cost me $800 and thats only because i knew the guy. get it fixed quickly before it costs you too much money. If you are hauling anything you should always put it on three.
 

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I have a 1993 Suburban, 1/2 ton 4WD with the 4L60E transmission. In 4th gear, overdrive, under load the transmission will shudder. If you press the brake pedal lightly or shift out of overdrive the shudder will quit. Other than that the transmission works fine, I don't notice any slipping. Fluid and filter was changed about 15K miles ago. I have heard that it could be either the TCC solenoid, TPS solenoid, a worn valve body, or even the torque convertor itself. Has anyone have experience with this or any thoughts or ideas? I just don't want to replace parts that I don't have to. Thanks for any advice!!
I will bet your problem is not the torque converter. A torque shudder will happen as it locks up. Once locked up the shudder goes away. Your problem sounds like an engine miss. The reason you can't feel it until lock up is because the fluid coupling masks the miss fire. Once it locks up you have a direct lock between the engine and transmission. The torque converter is basically out of the picture in lock up.
 

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shudder

I agree with the engine miss possibility. I chased what I thought was a torque converter lockout problem for a few months. It only seemed to happen when going up long hills or when returning to overdrive after using the passing gear the whole truck would shake but immediately run great if I put it in 3rd gear. After a month or so of this happening from time to time it got more frequent, then I started to get a P0300 code( random misfire). To make a longer story short it turned out to be my intake gasket (didn't show up on vacuum test for intake) one day it just started spewing water right behind the power steering pump.
 

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I have heard of the possibe missfire. I have repaceled the plugs, wires, cap and rotor since it needed to be done anyway. The shudder is still there. So I will assume it is still in the transmission. Should I replace the coil also, I assume this might still cause a missfire??
 

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I have heard of the possibe missfire. I have repaceled the plugs, wires, cap and rotor since it needed to be done anyway. The shudder is still there. So I will assume it is still in the transmission. Should I replace the coil also, I assume this might still cause a missfire??
A dirty injector would be more likely but it could be a coil. Have you ever changed the fuel filter?
 

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No I haven't replaced the fuel filter. I have a new one for it that I was going to replace it, the threaded connectors on the fuel line at the filter are rusted and stuck. I have been putting that off.
 

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It wouldn't be just a single cylinder miss if it's an injector, since that year only has tbi, and only 2 injectors. So if the injector was bad/dirty then the idle would be rough as well, and have a marked loss of power.
 

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I wasn't sure which year they switched from TBI to port injection? Good point.
 

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I have a 1993 Suburban, 1/2 ton 4WD with the 4L60E transmission. In 4th gear, overdrive, under load the transmission will shudder. If you press the brake pedal lightly or shift out of overdrive the shudder will quit. Other than that the transmission works fine, I don't notice any slipping. Fluid and filter was changed about 15K miles ago. I have heard that it could be either the TCC solenoid, TPS solenoid, a worn valve body, or even the torque convertor itself. Has anyone have experience with this or any thoughts or ideas? I just don't want to replace parts that I don't have to. Thanks for any advice!!
This is quite a bit later than the posting, but it may help others. I just read about a Tech Service Bulletin (TSB) about newer GM's with transmission shudder. GM says to have the transmission flushed with new Mobil 1 Synthetic LV ATF HP fluid. It is said to correct shudder and shifting problems.
 
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