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Chris (aka- Moose)
Chris (aka- Moose), Technician
Category: Transmissions
Satisfied Customers: 48691
Experience:  16 yrs. experience with auto, manual, & CVT drivelines
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I have 2008 CHEVY SILVERADO with duramax and allison tranny.

Customer Question

I have 2008 CHEVY SILVERADO with duramax and allison tranny. When it is under a load or I accelerate fast I get a chatter when it changes from 4th to 5th and 5th to 6th gear
JA: How old is the transmission? Have you checked the fuel filters? Are you fixing your Silverado yourself? What have you tried so far?
Customer: changed hanger bearing and all filters
JA: Anything else you want the mechanic to know before I connect you?
Customer: no
Submitted: 1 month ago.
Category: Transmissions
Expert:  Chris (aka- Moose) replied 1 month ago.

Welcome, I'm Chris (aka Moose).

  • Although I work here everyday, please understand it is not all day and rarely morning time.
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This really sounds like a torque converter clutch type noise. Does the noise seem to be coming from the transmission or from something outside the transmission?

Now that I have posted a partial or complete answer, you will see you can rate me. The deposit you have already paid is not transferred to me until you rate me. I would like to receive nothing less than 5 star excellent ratings. So if we are not there yet, please reply and let me help more. If you're not pleased, let me know because rating bad does not result in a refund, there are better options. Rating now will not close this post nor prevent replying. Thanks Chris

Customer: replied 1 month ago.
You can really feel the vibration through the gas pedal, It is like a chatter and really is worse when I have a trailer loaded that I pull. If I am accelerating fast with no trailer it still has the chatter but if I let off it stops. I have put it in trailer tow mode which is supposed to lock the torque converter and it still does it. It is hard to tell if it is coming from inside the trans or outside.
Expert:  Chris (aka- Moose) replied 1 month ago.

Thanks, ***** ***** things i would focus on is a converter clutch slippage issue or a locked up driveshaft u joint that is not wanting to bend.

Expert:  Chris (aka- Moose) replied 1 month ago.

Hello Chris here again,

I am checking in to make sure you got everything you expected from my answer. The option to rate my response or reply is still available. I want to make sure you were pleased with what you paid for.

Thanks Chris