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What would cause my C6 to not want to shift from 2nd to hi right away? I have to let off the gas before it will finally shift otherwise the engine will rev. From 1st to 2nd its fine. I had it rebuilt in '91, put about 4000 miles on it and parked it in '93. It had sit until now. I've changed the fluid and filter, checked the fluid level, its fine. Its all stock except for a B&M shift kit. Would sitting that long hurt anything? Does the vac. modulator have anything to do with this? Any suggestions? Thanks, Ryan.
 

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Hi, the vac. modulator shifts the trans unless it is wot but the problem is most likely the governor or clutches are sticking from sitting try putting a can of trans X in it and shift it manually for a little while so it has to shift and see what that does for it. John

Opal frost pearl metallic 67 coupe http://www.jps.net/binay/webdocs/febef75b01.JPG
also have a 95 opal frost pearl G/T BOSS edition convertible belongs to swmbo
 

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Just a thought...if the vacuum modulator hose is disconnected or kinked and the modulator isn't seeing any vacuum, it thinks the engine is at WOT and will take forever (literally) to shift....

The governor rpm (and pressure) won't get high enough during normal driving to overcome the throttle pressure from the modulator and shift the trans....

OTOH, the 2-3 shift valve might be sticking too...since the 1-2 is OK...*G*

Pat
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Did the tranny work fine before you parked it? If so it may just have a sticky plunger in the valve body or the servo could be sticking due to varnish buildup. I've had this problem myself with a C-4 that was parked for a long time. Try driving it some more and see if the new fluid will disolve the buildup.

Every day is a holiday if you love your job.

Current projects: 65 Fastback, 68 Coupe Oval Track Racer, 64 Galaxie 500 XL, 54 F-100 Pickup
 
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The transmission worked fine when I parked it. I checked the vac. modulator line, no kinks, checked the vacuum, it read 14 pounds. I've put about 400 miles on it so far.
 

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Ryan, I got it at advance auto it just cleans up varnish and sludge. It is a conditioner and sealer about $2.00 for a can I had a transmission guy tell me to put it in my truck with the same symtoms as you have my C6 never worked so good!!! John

Opal frost pearl metallic 67 coupe http://www.jps.net/binay/webdocs/febef75b01.JPG
also have a 95 opal frost pearl G/T BOSS edition convertible belongs to swmbo
 
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Thanks John, I think I'll try that first. By the way, nice '67!
 
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