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Discussion Starter · #1 ·
Had my transmission built 6 months ago by the transmission guy at work. All new clutches plates band sunshell 13 vane pump and dacco performance 2500 stall.

Car ran great for 6 months shifts hard and stiff. One night driving 6blocks started hearing a hissing noise at each shift point. Few more blocks and it would his louder than start slipping over 1/4 throttle. Same in forward and reverse.

Last week stripped it down and everything still looked brand new. He claimed my converter failed. Bought another one and threw it back on the var today. Drove it a few blocks shofts nice and fine. Let it idle at work checking fluid for about 30 minutes and drove it again. Made it about 200 yards and started hearinf the loud hissing/gurgling noise. Checked fluid level and didnt see any bubbles. Babied ot back to work and it would slip in reverse and drive and still made noise when revving in neutral.

In gear loading the transmission with the brakes on the noise would slightly go away and try to pull then lets go and makes noise again. Shut car off 3 4 minutes and pulled hard in the prking lot woth no noise or hesitation.

He claims he checked the pump and didnt see anything bad. Anyone have any ideas or agree with me its the pump?
 

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Discussion Starter · #2 ·
One dumb question tho. I filled the fluid while the car was running. With the stall being a 2500 does it still spin the pump enough to check fluid at idle or should I bring it off of idle and check it again. Car is locked up at work or I would have tried both ways.
 

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The pump spins whenever the engine is running. The converter HUB spins it, which is a mechanical link, not hydraulic. First question...Did you actually see him take your trans back apart? Or did he tell you everything was still good inside? Does the transmission still have the stock pan on it? This sounds like it may be sucking air. Most likely a damaged filter or filter seal. I've seen people put deep pans on with stock filters and have the filter fall out of the pump. Of course it might not even have a filter on it.

Frank
 

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Discussion Starter · #4 · (Edited)
Me and him work together at a GM dealership. I yanked it out and he stripped it all down bare. I checked it out myself. The band and all the clutches still look brand new since he built it 6 months ago. No signs of heat on the drum or the plates between the clutches either

Has the factory pan on it. Its doing the same thing when it starts to slip and makes the same hissing/gurgling noise. Out of no where just decides that when i take off nice and slow it starts when it shifts to 2nd and losses forward and reverse. Noise continues in neutral and changes as the rpm changes.

Only thing changed was the converter and fluid range pressure switch cause it had an intermittent dtc16 at wot few months back.

I sent him a few txts about it but he hasnt got to hear it himself. Hes out of work with a torn rotator cup.
 

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Discussion Starter · #5 ·
Guess Ill have to find another transmission guy to check it out since my coworker having surgery on his rotator cup
 

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Sounds like filter clogging maybe left over debris from converter failure or even a faulty filter the noise is caused by either cavitation of sucking air which can also cause the other symptoms and this can be filter , or over or under filled levels
 

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Discussion Starter · #7 ·
Filter is new since he stripped it down and put it back together a couple weeks ago. I was thinking the other day i never did see if the cooler is restricted. Transmission case was also bathed in the parts cleaner they use for all other transmissions at the dealership

One coworker road with me and said acts like too much gap between pump and stator or maybe worn rotor and rotor guide

The original transmission guy that built it both times just got out of surgery today and texted me saying not to worry about it and that he has another pump for me if thats the case.

Tomorrow i was going to check the cooler and if seems fine then going to pull it back out so he can inspect and change the pump if it needs it

He also originally told me theres no way to check if a converter has failed except to strip the trans down and see if there was any internal failure or not

Converter is painted silver so couldnt see if it were overheated and turning blue like Ive read before
 

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Discussion Starter · #8 ·
Just looking through my cellphone pics of when he last stripped it down and doesnt look like he ever seperated the pump and stator. Got pics of the drum and clutches and what little bit of debree was in the pan but cant really upload then from my phone right now
 

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Discussion Starter · #9 ·






These were taken last month when he stripped it down. Originally full rebuild back in July. Maybe 5k miles on it since the build.
 

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Discussion Starter · #10 ·
Went to my coworkers house last night and pulled a pump out of another 4l60e that has good pump but 3-4 clutch pack was burned up. Going to pull my trans out soon and cross my fingers. Will split the old pump just to see if there was any damage while its out.
 
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