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C4 trouble 4 me!

883 Views 5 Replies 2 Participants Last post by  Guest
Well I finally got my "rebuilt" engine and tranny in my '66, but I am getting engine rev between the 2-3 shift. The rest of the shifts are fine... any suggestions?

Also my old tranny was a "cruise o matic" ('66) and this C4 came out of a '68. Is there any difference from my old "dual range"??

At least the engine runs good...

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I have an Art Carr C4 with a reverse manual valve body. Mine will rev some on the 2-3 shift if my shifter linkage isn't adjusted just right. I have to make sure third gear on the shifter is clearly all the way into the detent on the transmission. Otherwise it seems that second disengages a split second too soon or third engages a split second too late which causes the rev. Mine still grabs hard when it hits so I'm pretty sure my 3rd gear clutches are ok.

You can see my 65 fastback at:
Sometimes a mis-adjusted intermediate band can cause a flare-up on the 2-3 shift...

You might want to double check it if the trans has been run in for a few hours now...the adjustment procedure is in your trans or service manual...

When rebuilding the trans, did you install a shift kit...?

Also, verify operation of the vacuum modulator hose with a vacuum gauge....

I installed a new vacuum modulator... and played with the adjustment. Didn't seem to help. I read the shop manual last night about the intermediate band adjustment. I'll give it a try. Does anyone have any advice or warnings?

Didn't install a shift kit... will it help? I thought the kit would only increase the shift point rpm's

Shift kit is a good'll firm up the shifts which seems to be what you're looking for...

I put one in the D-coder at 178K (on the original C4) and it made a world of difference in the shift quality...

Adjusting the vacuum modulator that comes with the shift kit will give you control over shift points when the trans is in Drive...

I'd still say adjust the band change at a never know, it might solve your problem...

BTW, could you give me your shift points right now under normal throttle...? Also, does the trans go into gear immediately when you shift from Park or neutral to reverse or drive? Or, is it a bit sluggish?

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It goes from park into rear and drive just fine... The 1-2 shift is nice and tight too. It's just the 2-3 shift. I'll look into the shift kit but I would hate to spend time and money on it if it won't help. If I can't get any results this weekend I'll have to take it into a tranny shop for a diagnosis... I don't know the shift points at normal throttle off hand. I'll pay attentiaon on the drive home.


<P ID="edit"><FONT SIZE=-1>Edited by sctkhouse on 03/23/01 06:22 PM (server time).</FONT></P>
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