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clutch piston?

M

murp9302

New member
Hi my names mitch I have a 1998 gtp stock the service engine soon light turned on and when it hits around 35 mphs it revs out and acts like its in neutral. How can I fix this and what can it be? Thank you for your time.
 


Take it to a autoparts store and have them read the SES - Service Engine Soon code. Once you have that, use it and search or let us know.
 
just curious what does "clutch piston" have do do with anything? and ya hve it scanned, get the code and let us know
 
RICE KILLER said:
just curious what does "clutch piston" have do do with anything? and ya hve it scanned, get the code and let us know
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Clutch piston (4 total) is what engages every clutch pack in the transmission. The way it works is trans fluid fills up the space on the bottom of the piston which then pushes the piston against the clutch steels and clutch friction plates. This then engages the clutch pack. If you didn't have a clutch piston the the clutch packs wouldn't engage.
 
Are the 4t60 and 65's prone to the stock apply pistons cracking? I know it's suggested to go to billet in the 4L60's in the trucks if you're doing a build up.
 
JJ91284 said:
Clutch piston (4 total) is what engages every clutch pack in the transmission. The way it works is trans fluid fills up the space on the bottom of the piston which then pushes the piston against the clutch steels and clutch friction plates. This then engages the clutch pack. If you didn't have a clutch piston the the clutch packs wouldn't engage.
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very well explained thank you.
 


chevy man said:
Are the 4t60 and 65's prone to the stock apply pistons cracking? I know it's suggested to go to billet in the 4L60's in the trucks if you're doing a build up.
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Two different things. The billet pistons recommended for the 4L60s are the servos, which are different from the clutch piston. There was issues with the accumulator pistons as well, weren't some plastic?

To answer the question, no, it's not common for the accumulator or servo pistons to crack in the 4T65.

murp, I doubt it's the clutch piston, more likely a solenoid or something. Get that code and let us know.
 
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I took it to a shop and they ran the code he wouldn't tell me what the numbers were all he said was the clutch piston was sticking open its my girlfriends car I checked the trans fluid and its thick and needs a change do u think a good flush and an additive would help it at all or just spend the $300 to have the clutch piston replaced? Thank you guys again.
 
murp9302 said:
I took it to a shop and they ran the code he wouldn't tell me what the numbers were all he said was the clutch piston was sticking open its my girlfriends car I checked the trans fluid and its thick and needs a change do u think a good flush and an additive would help it at all or just spend the $300 to have the clutch piston replaced? Thank you guys again.
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If he won't tell you the trans code, then don't even consider having him fix it. Clutch pistons in 4t65e's don't really fail from what I've seen. You can have a seal that gets torn or that rolls out on the input clutch drum but that's not even that often.

Trans fluid might help some, but in all honesty it probably won't do much.

Trans additive usually is just a bandaid and can actually cause more damage/harm to the trans.

Recommendation

Go to another BIG trans shop and have them diagnose it. Tell them if they expect to make any money off you, that you want the trans codes to research what they say online. If they don't want to give you the code, then tell them it would be irresponsible on your part not to follow up. Come back here once you get the code and post it here.
 
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