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[oletrucks] 700R4 WILL NOT UPSHIFT!!!

To: oletrucks@autox.team.net
Subject: [oletrucks] 700R4 WILL NOT UPSHIFT!!!
From: CLLLSLS@aol.com
Date: Wed, 30 Aug 2000 00:23:18 EDT
Hey everyone,

I have an emergency here. I've put together a ground pounding small block, 
700R4 and 3.73 posi and stuffed them in my '79 silverado. The scary part is 
that I did it all on a 17 year olds budget at around $1800. A budget like 
that lends itself to corner cutting. The tranny came from a friends 84 buick 
station wagon he used to run over mailboxes, portapotties and varius 
streetside shrubs before he cut the car up and parted it out. The tranny saw 
several nuetral drops, but worked fine when the car was last run. I pulled 
the valve body, and with the exception of a shattered accumulator spring and 
browned fluid, the tranny was awesome. I installed a stage 2 shift kit and 
put her back together. 

I put her in the truck, filled her up with dexron, adjusted the linkage and 
ran her through the gears , adding fluid, just before I pulled it up to 2 
grand for the cam break in.

After I adjusted the lifters, I took the truck to my work to weld the flows 
on and she will not upshift from first gear. I DID NOT have the TV cable 
hooked up at that time which everyone told me was my problem. The cable was 
not long enough so I rigged it with wire and tried it again. No shifty again. 
And yes, I did have the TV cable adjusted correctly with proper throw, etc. I 
even pulled the tranny pan to verify the throttle valve was working, through 
it's entire range, with the throttle movement. The tranny will go in reverse 
and into first with no problem. It even shifts reasonably hard as it's 
supposed to into first and reverse.

I could not get a hold of my friend who owns a tranny shop today as he was 
out and about today. I talked with one of his employees and called other 
tranny shops all giving the same reply of "bring it in, we have to see it". I 
have about $100 dollars I can afford to spend which will not cover bringing 
the truck to a tranny shop. I can do the repairs myself if I knew what to buy 
and what fix. My shop manual offers "misadjusted TV cable, misadjusted 
intermediate band or internal fault" as causes for not upshifting from first. 
I'm confident it is not the TV cable as it is working. However, I could 
understand misadjusted intermediate band or internal fault because I noticed 
that past where the shiftpoint should be, if I let off the throttle, as if to 
force it to shift, the truck "freewheels" as if in nuetral. The truck had an 
8.5:1 cr before and it slowed down quickly, with the current 10.2:1 I would 
expect the engine to slow the truck down even faster, especially with the 
lower first gear than the turbo 350. Does this sound like the intermediate 
band could be misadjusted or even broken so that the transmission is shifting 
into second, but the band is not catching?

I'm lost. All my transmission books are too old to cover 700R4's. Can anyone 
suggest a good book or website or anything that would help me here. I've 
heard the factory GM manuals are good and very detailed. I'm sure they make 
one for the 700R4, can anyone suggest if it's a good investment?

Please help! I should be able to get a hold of my tranny shop owning friend 
tomarrow, but I don't know what he will say. If you could offer any advice I 
could really use it! Thanks,

Dustin
50 & 53 GMC 1/2 tons
48 GMC 3/4 ton
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959

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