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Posted

Hi guys,

I have a new problem with my transmission. When I drive down the road with 45-60mph and low rpm 1000-1500, the problem starts after I lift the gas paddle. The truck stutter, rpm stay straight, but it feels like the transmission shit in and out but not between the third and fourth gear (no shifting no rom change) and it only is in fourth gear. 

 

Transmission oil change 4 weeks before, new filter, oil Level ok, oil color also good.

 

is this a transmission or engine problem?

Posted

Diagnostics

 

- does apply brake slightly improve things? If yes, then torque converter problems

 

Also

 

- meter to check that computer is getting good sensor signals

 

EDIT: sensor signals

Posted

Hi, thanks for the answers. Im not the best in doing all the stuff on my one. Also Im very sad about GM leave Europe a while ago.

I tried to apply the brake with the car studderd. It doesen`t matter. Only in low rpm and 4th gear. If I lift the gaspedal a moment and step on full trottle, it shits down an all goes well. No studdering at all.

It is a 4th gear low rpm problem.

Do the Limp mode make codes into the computer without light up the engine light?

 

Thanks Sebastian

Posted

I think you’re saying the torque converter is locking and unlocking? That causes rpm’s to go up and down slightly but it goes away when you go faster than 60 mph. If that’s the case, the problem can be solved by shimming the torque converter control valve springs with ¼ inch ball bearings. I know because that how my brother in law fixed mine. You just gotta’ find someone that knows what they’re doing.

Posted

My rpms aren‘t doing anything. No shifting, only stiffening. Some problem in 3rd gear. Low rpm and getting faster outside the city limits. No kickdown, just slowly speeding up with no throttle.

Posted

Hello,

Today arrived my gm tech 2 tester. I don’t have and transmisson code only fuel Pumpe high voltage code p0463. But I saw on live data, that the problem is, when tcc is enabled in 4th and the tcc slippage goes on zero, in the moment 0rpm are reached, the car studdering and the slipage goes anywhere between -6rpm and 4rpm not steady on 0rpm. 

 

Would this be solved with a new rebuild valve body?

 

Thanks

  • 2 weeks later...
Posted

I'm going to try here.......it sounds like you're describing one of two things: Either you're experiencing a "fish bite" misfire (which will typically unlock the torque converter when the PCM detects multiple misfires), or you're getting "hunting" at highway speeds. If the RPM isn't fluctuating much and the torque converter is staying locked with close to 0 RPM slip, then I would try inspecting and cleaning the MAF sensor, as it is a common culprit for TC hunting.

Posted

Transmission shift points are controlled by the computer. The computer uses current gear, rpms (if low shift down, if high them shift up), and tps angle ( does the driver want to go faster - WOT, slower -0 angle, cruise so TCC lockup), vehicle speed, etc

You'll want to use the scanner to monitor these items and what gear is being commanded. If the gear shifts are not matching the command then some valve, check ball, is likely sticking.



Posted

I didn‘t scan any misfire especially if the studdering happens. I will clean the maf to see, but also the new valve body with upgraded tcc valve arrived. Hope to fix that with new siloides and new gaskets.

  • 2 weeks later...
Posted

Have my valvebody disassembled today. 

Habe few new questions:

1st: do I need a new pressure valve manifold? See pictures. 

2nd: do I need a new oring for the tcc silinoid?

3rd: do the oil filter need a new ring or bushing where he is fixed?

4th: I have this dipstick holder not die pen with the egde. How deep should the dip stick goes into the pen? My stick ends right when he comes out of the tube and goes only half a centimeter into the oil pen.

 

3BF5658F-39CF-4472-990F-DC3B13CA779A.jpeg

04329C44-54AD-4618-B792-C353AD508874.jpeg

Posted

1-3: No, but it doesn't hurt to replace the orings. As long as they're not scratched or cut, you can reuse them.

4: Dipstick is fine. That's how its supposed to be. Just be sure that the small metal clip that bolts on that corner is present, unless you have the crimp in the oil pan on that corner.

Posted

There are 4l60e valve body rebuild kits that include all the parts typically recommended.

New valves, orings, check balls, etc. Suggest putting one of these in to get all those components that might look good but are border line.

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