Rebuilt C4 problem

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Jan 12, 2003 | 02:23 PM

nickmobile67

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Joined: Jul 2002

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From: East Coast

Rebuilt C4 problem

Ok, I have a C4 that was just rebuilt. Shifts fine when cold, but after it's been running for 10-15 min (up to temp I guess) the 2 to 3 shift is odd. 1 to 2 is always fine, but when it gets up around 2200 RPMs in 2nd (normal shift point) it quickly revs up to about 3000 before dropping into 3rd. (vrrrrrrrrrVROOOOOOOO rrrrr) Also helps if you let off gas. I had adjusted the vacuum modulator a while back (shouldn't have) so I replaced it today with a new one. Better than it was, but still there. Wierd. I'm not touching the new modulator because I know it is factory set. I tried adjusting the kickdown linkage aswell. Anybody ever experience this before? Should I adjust the kickdown more? (seems OK where it's at now) Should I just call the rebuilder and have him worry about it? (that is what I'll do if I don't get a simple answer) TIA

Jan 16, 2003 | 07:03 PM

joetee10

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Joined: Oct 2002

Posts: 194

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From: united states

Rebuilt C4 problem

Sounds like loose tolerances internally, causing the band to slip. Best thing to do is take it back to the tranny guy. That way if its his fault he can fix it and not blame you for messing around with it first.

Jan 17, 2003 | 09:30 AM

rabidranger

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Joined: Nov 2001

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From: -

Rebuilt C4 problem

Get a haynes manual and retorque the band adjustment bolts on the outside of the case. Follow the torquing steps to the letter. Also check for vacuum leaks to the modulator on the tranny.