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Another 4L60 Issue

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Old Jun 24, 2014 | 11:00 PM
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Default Another 4L60 Issue

I'll just jump to the "here's what happened":

So for the first time in two weeks it was a nice day outside (its a five mile drive through the city) so I decided at the last minute to drive the Trans Am to work after about two weeks sitting in the garage. About two months ago installed cam/heads/3600 PTC converter and had it tuned (and have a trans cooler mounted on the radiator). I checked the trans fluid and it was still red, didn't smell burnt. Car usually cruises between 1500-2000 RPM. About half way to work there is a big hill, so as I started back up it my RPMs climbed to 3,000 which was kind of weird, but it was a humid morning and it leveled back down to about 2500. About half a mile from work the RPMs climbed to 4,000rpm then 5,000rpm just before I hit the parking lot just to keep the car moving.

I went into work and had it towed back home after the day was done. Reverse works flawlessly and the trans operates like normal up to 20mph. After that, it climbs back up to 5,000rpm to accelerate further. Trans fluid is now a darker, not quite yet brown, but it is definitely burnt. Motor also started misfiring (no code thrown) after I got it backed into the garage, so I pulled the plugs and two were fouled with the rest on their way. Should have them changed by Wednesday when the plug/wire set is supposed to arrive from RPMSpeed (they're just down the road from me )

Haven't found a thread searching in the last 48 hours with this exact issue, so I figured I'd just confirm before I start tearing it out, is it the transmission, or do I have something that got knocked loose? FYI, trans was rebuilt in 2007.
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Old Jun 25, 2014 | 10:00 PM
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Anyone? Changed the plugs/wires tonight.
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Old Jun 25, 2014 | 11:07 PM
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Sounds exactly like the 3/4 clutch suddenly wore out which is often due to a leak in the finicky 3/4 clutch hydraulic circuit. Or just too many miles and/or too much power.

With your mods and especially the NO 150-shot, you need much better than a stock rebuild and should consider a mid-level 4L65E from one of the sponsors or swapping to a 4L80E.
This current thread is addressing the options:
https://ls1tech.com/forums/automatic...do-i-need.html
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Old Jun 26, 2014 | 11:34 AM
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Already planning on a new trans this winter, was hoping it was make it through the summer with easy driving.

FYI, haven't run nitrous or raced the car yet, motor has literally been done for about a month.
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