P0740 TCC Failure
Joined: May 2006
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From: Sheboygan Wisconsin






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Posts like a Turbo
Joined: Mar 2009
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From: Richmond,Va.

RockAuto didn't list the upper tube on their website so I called them and they only carry the one for the na 3800 not the supercharged models. I guess I'll put in a request in the wanted section. Any ideas?
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From: Richmond,Va.

No, not yet. I still haven't fixed the leak in the egr tube but hopefully I will get that done tomorrow. One possibility is the valve body in the tranny. I haven't taken it to a transmission shop for diagnosis but some people have had success with valve body kits.
I gather this may be the fix
Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: Transmission :: 84754-97K :: Part Summary
I would try installing an aux tranny cooler to try and fix the issue before that...
Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: Transmission :: 84754-97K :: Part Summary
I would try installing an aux tranny cooler to try and fix the issue before that...
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From: West Brookfield, MA

The part that Johnd89 mentioned probably won't help you. That valve controls the on off function for the tcc. Your tcc is turning on. The problem is low apply pressure for the clutch. This is the part that would most likely help you.
Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: Transmission :: 84754-01K :: Part Summary
This valve has extreme wear since it constantly buzzes in the bore while tcc is engaged. The other valve just clunks back and forth for engagement and disengagement.
I do not recommend going into the valvebody unless you have experience working on trannies. I have seen many people in the trade make mistakes.
But if you do try, Make sure you have new valvebody gaskets ready. And don't lose any of the check balls that will fall out.
Sonnax Transmission, Torque Converter, Performance, Driveline Parts :: Transmission :: 84754-01K :: Part Summary
This valve has extreme wear since it constantly buzzes in the bore while tcc is engaged. The other valve just clunks back and forth for engagement and disengagement.
I do not recommend going into the valvebody unless you have experience working on trannies. I have seen many people in the trade make mistakes.
But if you do try, Make sure you have new valvebody gaskets ready. And don't lose any of the check balls that will fall out.





for the clarification Tequila Man!